Of particular concern was the power system – RTGs, the only current system that would feasibly power such a probe on Titan’s fully enveloped surface, would be too heavy for such a mission architecture. So, Mr. McKevitt changed tact and created something entirely different.

During COVID-19, he created an organization known as Conex Research to explore complex missions in a collaborative think-tank format. He then adapted Astraeus, as the mission was known, to a more achievable format, which was then described on Conex’s website. In a press release from August of 2022, the mission had morphed into a four-part system.

First is a “Main Orbital Spacecraft,” which would orbit the Moon Moondeploy two smaller vehicles – Mayfly and Manta. As their names suggest, Mayfly would flit about as an aerial observation platform, while Manta would dive into the lakes that were so intriguing in the original mission architecture. A series of 2U Cubesats, called “Mites,” would also join them and measure different parts of Titan’s atmosphere during a slow descent period after being released from the MOS.

That sounds like a pretty hefty lift, especially for a group of volunteer contributors, even if there are almost 30 of them. Lately, the group hasn’t had much of an update since they presented the mission format at the International Astronautical Conference in 2022. But if they are still making progress on the mission, there is a chance it might one day make it all the way to the bottom of one of Titan’s lakes.

Learn More:

• James McKevitt – ASTrAEUS: An Aerial-Aquatic Titan Mission Profile
• Conex Research – The Astraeus Mission to Titan
• UT – Scientists Construct a Global Map of Titan’s Geology
• UT – Titan May Have a Methane Crust 10 Km Thick

Lead Image:

• Surface of Titan (left) with modeling mockups of the Mayfly (middle) and Manta (right).
  Credit – Conex Research

{ https://www.universetoday.com/ }

26-12-2024 om 22:01 geschreven door peter  

Related to that, for several years cosmologists have recognized a certain tension in their measurements of the present-day expansion rate of the universe, called the Hubble rate. Appropriately called the Hubble tension, the difference comes when comparing measurements of the distant, early universe with measurements of the later, nearby universe.

There’s definitely something funky going on here, but cosmologists can’t figure out exactly what. It might have something to do with our measurements of the deep universe, or it might be because of our lack of understanding of dark matter and dark energy. Either way, the James Webb didn’t help anything by confirming that the tension is very, very real.

No matter what comes out of the Hubble tension problem, the James Webb is delivering spectacular results in other areas. One of its primary missions was to find evidence for Population III stars, the first generation of stars to appear in the universe. There are no such stars left in the modern-day cosmos, as they all apparently died off billions of years ago. So our only hope to detect them is to use super-telescopes like the James Webb.

This year a team reported the first tentative detections of a galaxy in the young universe that just might contain Population III stars. The detection is not confirmed, but hopefully upcoming observation campaigns will tell us if we’re on the right track.

No matter what, we know we have a lot left to learn about the universe, and that the James Webb will continue delivering results – and hopefully a few surprises – for years to come.

VIDEOS

{ https://www.universetoday.com/ }

26-12-2024 om 21:26 geschreven door peter  

Mystery of Siberia's giant exploding craters may finally be solved

But the historic-lake model fails to account for the fact that these "giant escape craters" (GECs) are found in a variety of geological settings across the peninsulas, not all of which were once covered by lakes, according to the new preprint, which has not been peer reviewed.

Related: 

• US Space Force satellite data shines light on mystery of Arctic warming

Previous studies have also linked the craters to accumulations of natural gas within the permafrost, but these can't explain why the holes are only found in northern Russia. "Thus, the formation of GECs points to conditions specific for the Yamal and Gydan peninsulas," researchers wrote in the preprint.

Image taken in 2014 showing one of the craters on Russia's Yamal peninsula. 

(Image credit: VASILY BOGOYAVLENSKY/AFP via Getty Images)

Permafrost on the Yamal and Gydan peninsulas varies widely in its thickness, ranging from a few hundred feet to 1,600 feet (500 m). The soil likely froze solid more than 40,000 years ago, imprisoning ancient marine sediments rich in methane that gradually transformed into vast natural gas reserves. These reserves produce heat that melts the permafrost from below, leaving pockets of gas at its base.

Permafrost in Russia and elsewhere is also thawing at the surface due to climate change. In places where it is already thin on the Yamal and Gydan peninsulas, melting from both ends and the pressure from the gas may eventually cause the remaining permafrost to collapse, triggering an explosion.

This "champagne effect" would explain the presence of smaller craters around the eight giant craters, as huge chunks of ice propelled out by the explosions may have severely dented the ground, according to the preprint.

There may also be more of these craters than we realize, the researchers added, as water and sediment likely filled some of the holes over time.

The release of natural gas and methane during these explosions could activate a climate feedback loop if global temperatures continue to creep up and accelerate permafrost melting. 

"The formation of GECs has been connected to global climate change, with increasing summer and fall temperatures resulting in permafrost warming and degradation," the researchers wrote.

An estimated 1,900 billion tons (1,700 billion metric tons) of greenhouse gas, including carbon dioxide and methane, are stored in the Arctic permafrost, according to the preprint. Growing emissions from thawing permafrost "are of great concern," the authors added. 

VIDEOS

{ https://www.space.com/ }

25-12-2024 om 23:58 geschreven door peter  

How did the Moon form?

Earth’s Moon was born out of destruction.

Several theories about our Moon’s formation vie for dominance, but almost all share that point in common: near the time of the solar system’s formation, about 4.5 billion years ago, something ― perhaps a single object the size of Mars, perhaps a series of objects ― crashed into the young Earth and flung enough molten and vaporized debris into space to create the Moon.

Earth’s Moon is thought to have formed in a tremendous collision. A massive object ― named Theia after the mythological Greek Titan who was the mother of Selene, goddess of the Moon ― smashed into Earth, flinging material into space that became the Moon.

NASA

The early solar system would have been a chaotic, terrifying place. Debris left over from the formation of the Sun coalesced into a disk around the star, creating clumps that ranged in size from dust flecks to minor planets. Gravity drew these objects together, causing them to crash into each other ― violent smashups that could end in obliteration or new, larger objects. Those mashed-together objects make up the planets, moons, asteroids and other solar system objects we know today.

A Unique Beginning | How the Universe Works

Written in Stone

Visiting the Moon with the Apollo missions in the late 1960s and early 1970s revolutionized our understanding of the Moon’s origins. Previous concepts ― that the Moon was an object captured by Earth’s gravity as it sailed by, or that the Moon formed alongside Earth from the same debris ― fell out of favor after the Apollo missions brought back data and 842 pounds (382 kilograms) of lunar samples to Earth in the late 1960s and early 1970s. The Apollo evidence all pointed to the Moon forming from a large impact. The age of the rock samples indicated that the Moon formed around 60 million years after the solar system began to form. The type and composition of the samples showed that the Moon had been molten during its formation and was covered with a deep ocean of magma for tens of millions to hundreds of millions of years ― an environment that would occur in the aftermath of an intensely energetic impact. Lunar rocks were found to contain only small amounts of elements that vaporize when heated, further indicating the Moon could have formed in a high-energy impact that let those elements escape.

Five Things We Learned from Apollo Moon Rocks

1. The chemical composition of Moon and Earth rocks are very similar.
2. The Moon was once covered in an ocean of magma.
3. Meteorites have shattered and melted rocks on the Moon’s surface through impacts.
4. Lava flowed up through cracks in the Moon’s crust and filled its impact basins.
5. Lunar “soil” is made of pulverized rock created by meteorite impacts.

Scientist and astronaut Harrison H. Schmitt stands next to a huge, split lunar boulder during the Apollo 17 mission at the Taurus-Littrow landing site in this photograph from Dec. 13, 1972. Rock samples collected during the Apollo missions provided evidence that the Moon resulted from an object crashing into Earth in the early history of the solar system.

NASA/Eugene Cernan

Perhaps most importantly, the rock samples indicated that the Moon was once a part of Earth. Basaltic rocks from the Moon’s mantle have striking similarities to basaltic rocks from Earth’s mantle. The oxygen isotopes and other elements sealed into the specimens matched those of Earth rocks too precisely for the similarities to be a coincidence.

Meteorites make up another body of evidence. Samples collected by Apollo astronauts come from just a few sites on the Moon, but lunar meteorites ― rocks sent into space by impacts on the Moon that eventually find their way to Earth ― provide samples from all over the Moon that tell a similar tale of the Moon’s history. Meteorites originating from asteroids have also been used to help confirm the timeline of the Moon’s formation. Some show signs of having been bombarded by debris from the giant, Moon-forming impact.

Finally, more recent studies add the evidence for a high-energy impact that resulted in the creation of a molten Moon. Analysis of light reflecting off the Moon gives details of the mineral makeup of the Moon’s surface, and it shows the widespread presence of anorthosite, an igneous rock that crystallizes out of and floats to the top of magma. The presence of anorthosite across the Moon’s surface reinforces that the Moon must once have been covered by a widespread magma ocean that was quite deep, from hundreds to thousands of kilometers.

This light-colored mineral, Apollo mission lunar sample 60639, is thought to have floated to the top of the magma ocean and formed the Moon's first crust around 4.4 billion years ago.

Lunar Sample Laboratory Facility for Astromaterials 3D Explorer

Lunar “Archaeology”

Though Earth and Moon both came from that ancient collision ― and Earth is certainly within easier reach ― studying the Moon gives us our best chance of understanding what happened all those billions of years ago. Earth’s active geological processes, from plate tectonics to erosion, erase the evidence of formation. Aside from events like impacts, much of the Moon’s surface changes on a vastly slower timescale. Like detectives at a crime scene, scientists use clues preserved on the lunar surface to piece together the Moon’s history. Any improvements to the giant impact theory or a new theory would need to explain what we observe of the Moon today.

One of the oddities is the Moon’s low iron content as compared with Earth’s. Earth’s iron-rich core accounts for around 30 percent of its mass, but the core of the Moon is only about 1.6-1.8 percent of its total mass. One possible explanation is that the energy of the impact with Earth that formed the Moon vaporized lighter materials, casting them into space, and left behind heavier elements ― such as iron, which vaporizes only at extremely high temperatures ― to sink into Earth’s core.

This diagram shows a cross-section of the Moon’s interior during its early history, including the silicate mantle and a small metallic core. The lunar mantle is low in the elements 14 zinc, tin, cadmium, indium, and thulium, possibly because they never recondensed from gas form after the collision that created the Moon.

Illustration courtesy of NASA/JPL-Caltech

Any viable theory of lunar formation also has to explain where the Moon is now in relation to Earth and the speed and inclination of its orbit. Surface reflectors placed on the Moon during Apollo show that the Moon moves away from Earth at the rate of about an inch and a half per year. This indicates that the Moon initially formed much closer to our planet, and, therefore, that the early Earth’s spin rate was much higher than it is today. Computer models created by scientists to test and analyze Moon formation theories must show how a massive collision can produce the existing orbits and rotation of Moon and Earth over billions of years when paired with the typical gravitational interactions between the two bodies. (Even today, the distance between the Earth and Moon, and the length of a day on Earth, continues to grow due to the effects of Earth’s tides.)

Finally, strange discrepancies exist between the Moon’s near and far sides. Differences include: the thickness of the crust ― 43 miles (70 kilometers) on the Moon's near-side versus 93 miles (150 kilometers) on the far side; the contrasting geological makeup, including a concentration of radioactive elements on the near side; and the rich history of volcanism on the near side compared with a relative lack of volcanic activity on the far side. How closely these differences are related to the Moon’s formation ― how it cooled, how its volcanic activity took place, and the manner in which it has been bombarded by objects from space ― is a question scientists continue to wrestle with today.

The Moon's near side and far side.

NASA LRO / Jatan Mehta

Model Behavior

With humanity’s return to the Moon through the Artemis program, scientists expect a flood of new information that will help us hone in on a single formation scenario. In the meantime, scientists continue to study existing samples and other information they have now ― such as information from lunar orbiters and the growing body of knowledge on planetary formation ― to construct computer models that help us understand how the collision might have happened, and how it could have resulted in the Moon and Earth as we see them today. The models account for factors like the strength of the colliding objects, the friction between the components, the density of the components, and how materials behave under different temperatures and pressures. Today’s advanced computer models can provide a number of very specific outcomes based on variables like these.

For instance, when scientists want to figure out why the Moon is low in certain elements that vaporize easily, they use models to see how the Moon’s composition would look if the elements were lost, or depleted, during different periods of the Moon’s formation. Perhaps the environment in which the Moon formed or early eruptions on the Moon’s surface created a temporary atmosphere that led to the elimination of some of those elements, or they may have been released through interactions with the heat of the Sun or a bright and still-molten Earth.

Even these complex models can’t simulate every atom in a massive collision between giant objects that kicks debris into space. But astronomers can represent larger groups of debris by using particles whose properties depend on where they are located during the collision, like hot material situated near the proto-Moon’s core. Astronomers are able to alter the properties in their models to produce different results, showing how even small changes can produce different scenarios. As evidence continues to come in, the eventual goal is a comprehensive model that accounts for everything we know about the Moon.

Searching for the Past in the Future

The final Apollo Moon mission was in 1972. Scientists have had decades to investigate lunar samples and data from the Apollo missions, combine it with information returned by subsequent lunar missions, come to conclusions, and form new questions. They know what to target during the upcoming Artemis missions to help solve some of the outstanding mysteries.

All of the Apollo missions landed near the Moon’s equator, and the samples brought back are mostly from volcanic regions. Lunar scientists are hoping to obtain new samples from different locations, like the far side of the Moon and areas closer to the poles, so they can examine the Moon’s composition in regions that would have evolved in different ways and uncover more evidence of how the Moon formed. They’re hoping to drill down into the lunar surface and acquire core samples that expose additional layers of the Moon’s geologic history, a record written in rock and mostly hidden from us for now.

These new discoveries will help narrow down the many unknown factors in the Moon formation models. If the new evidence shows ― to choose just one example ― that a vast quantity of sulfur was lost during a period of volcanic activity, then that sulfur loss doesn’t need to be accounted for during early stages of Moon formation. Like a game of Clue, deciphering the mysteries of the Moon’s formation will be a process of elimination, ruling out particular events happening during certain time periods and narrowing down the possibilities until few remain.

But scientists are also alert to the possibility of new discoveries, findings that paint a different picture. The greatest clues to the Moon’s past may still be scattered around and beneath the lunar surface, waiting to be unearthed.

• Writer: Tracy Vogel
• Science Advisors: Prabal Saxena (NASA's Goddard Space Flight Center), Sarah Valencia (NASA's Goddard Space Flight Center) and Bill Bottke (Southwest Research Institute Boulder)

{ https://www.nasa.gov/ }

25-12-2024 om 01:20 geschreven door peter  

Studie onthult dat de maan veel ouder is dan gedacht (en legt ook uit waarom we het verkeerd hadden)

Vivian Lammerse

{ https://scientias.nl/ }

25-12-2024 om 00:59 geschreven door peter  

NOIRLab Releases High-Resolution Images of 88 Constellations and Colossal Photo of Night Sky

NSF’s NOIRLab, in collaboration with ESA/Hubble, has released a collection of free, high resolution images of all 88 constellations and the largest open-source, freely available all-sky photo of the night sky.

This all-sky photo of the night sky was compiled using images taken by astrophotographer Eckhard Slawik from the best and darkest locations around the globe.

Image credit: NOIRLab / NSF / AURA / E. Slawik / M. Zamani.

“This complete collection of free, high resolution, downloadable images of all 88 western IAU-recognized constellations serves as an educational archive that can be used on the individual and scholastic levels,” NOIRLab astronomers wrote in a statement.

“The project also includes the release of the largest open-source, freely available all-sky photo of the night sky.”

The photographer behind these stunning, high-quality images is the German astrophotographer Eckhard Slawik.

“The images were taken on film and each panel comprises two separate exposures, one with and one without a diffuser filter to allow the stars’ colors to shine through,” the astronomers said.

“All products include a comprehensive description of the constellation and its historic origins, as well as the corresponding standardized stick figure, outline drawing, finder chart and description of the constellation’s most prominent deep-sky objects.”

“Existing astronomical images of such deep-sky objects, captured with various NSF’s NOIRLab telescopes, are also included.”

“Downloadable flash cards and other audiovisual and educational materials make it easy to bring the constellations into the classrooms.”

The NOIRLab astronomers also released the largest open-source, freely available all-sky photo of the night sky.

“With 40,000 pixels, this is arguably one of the best such images ever made,” they wrote.

“The colossal sky-scape was compiled using images taken by Slawik from the best and darkest locations around the globe: in Waldenburg, Germany; Tenerife, La Palma, Spain; Namibia; and Chile.”

“The 88 Constellations images are open for exploration by all ages, and are especially suitable for use in planetariums and museums.”

“Visit the project webpage to become familiar with all 88 constellations and see how many you can spot in your night sky.”

{ https://www.sci.news/ )

24-12-2024 om 00:00 geschreven door peter  

CIA docs claim life did exist on Mars... and it was a population of 'very large people' who built pyramids

• READ MORE:  Scientists make discovery on Mars that could reveal alien life

By STACY LIBERATORE FOR DAILYMAIL.COM

While NASA is searching for life on Mars, a CIA document claims it was found 40 years ago.

The report, 'Mars Exploration May 22, 1984,' details how the agency used astral projection—the idea that a person's spirit can travel through the astral plane—to transport a 'subject' to Mars approximately one million years BC.

The study was part of Project Stargate, a secret US Army unit established in 1977 that focused on anomalous phenomena, including remote viewing, telepathy, and psychokinesis.

Participants were exposed to sounds like binaural beats and hemi-sync audio to induce altered states of consciousness and promote psychic abilities.

The experiment's 'subject' was transported to the planet during the specified year, reporting an 'oblique view of a pyramid' and a 'very large road' with a monument similar to those known among ancient Egyptians on Earth, the report claims.

The vision then shifted to a population of 'very large people' searching for 'a new place to live because their environment was corrupted.'

Project Stargate was the US government's new weapon against the Soviet Union, aimed at creating mind-reading spies who could infiltrate the minds of its enemies.

The classified project was conducted at Fort Meade in Maryland, recruiting men and women who claimed to have extrasensory perception (ESP) to help uncover military and domestic intelligence secrets.

The experiment's 'subject' was transported to the planet during the specified year, reporting an 'oblique view of a pyramid' and a 'very large road' with a monument similar to those known among ancient Egyptians on Earth

It shut down in 1995, but during its more than 10-year existence, psychics known as 'remote viewers' participated in a wide array of operations, from locating hostages kidnapped by Islamic terrorist groups to tracing the paths of fugitive criminals within the US.

Leading up to its closure was 'Mars Exploration May 22, 1984,' a document declassified in 2017 that has recently resurfaced online.

The document is sparse in details, beginning with: 'Method of site acquisition: Sealed envelope coupled with geographic coordinates.'

The envelope was provided to the subject before the interview but was not opened until afterward.

'In the envelope was a 3x5 card with the following information: The Planet Mars. Time of interest approximately one million BC,' the document reads.

The administrator of the experiment verbally relayed the envelope contents and allowed the subject to provide their observations. The starting time was 10:09 a.m. ET.

The subject was asked to focus their attention on '40.89 degrees north, 9.55 degrees west.'

'It sort of looks... I kind of got an oblique view of a ah... pyramid or pyramid form,' the subject said.

While NASA is searching for life on Mars , a CIA document claims it was found 40 years ago

They continued to describe the structure as okra-colored, a hue ranging from yellow to deep orange and brown.

The subject then observed shadows of 'very tall, thin' people wearing strange clothing.

The administrator prompted the subject to remain in that time period but move to another location in space.

The landscape featured a very long road with what appeared to be the Washington Monument at the end.

'It's like an... obelisk,' the subject said before being asked to move to different locations until they saw people again.

The subject moved to a place where a violent storm was ripping through Mars, and people were using the giant pyramids for shelter.

'Different chambers... but they're almost stripped of any kind of... furnishing or anything. It's like ah... strictly functional, a place for sleeping—or that's not a good word—hibernation, some form,' the subject said. 

I can't... I get real raw inputs, storms, savage storms, and sleeping through storms.'

The experiment suggested that a population of people died on Mars after intense storms ripped through the planet

The administrator asked the subject to describe who was sleeping through the storms.

'Very... tall again, very large... people, but they're thin. They look that way because of their height, and they dress like in, oh hell, it's like a real light silk, but it's not flowing type of clothing. It's like cut to fit,' they explained.

The subject told the administrator that these were ancient people who were dying.

'It's past their time or age,' the subject said. 'They're very philosophic about it. They're looking for ah... a way to survive, and they just can't.'

The subject appeared concerned for the ancient people, saying they were looking for a way out or waiting for something to return.

'It's like I'm getting all kinds of overwhelming input of the... corruption of their environment,' the subject said. 

'It's failing very rapidly, and this group went somewhere, like a long way, to find another place to live.'

The subject claimed to have spoken with one of these people, who told them that a group had left in what 'looks like the inside of a larger boat.'

The administrator told the subject to go along on the journey and report what they saw.

'Impression of a really crazy place with volcanoes and gas pockets and strange plants—a very volatile place. It's very much like going from the frying pan into the fire,' the subject said.

'The difference is there seems to be a lot of vegetation where the other place did not have it. And a different kind of storm.'

The administrator then told the subject it was time to come back.

'Move now back to the room, back to the sound of my voice, back farther now to the sound of my voice on the 22nd of May, 1984,' they told the subject.

{ https://www.dailymail.co.uk/  }

23-12-2024 om 21:31 geschreven door peter  

• READ MORE: Earth is 'overdue' a devastating solar SUPERFLARE, scientists warn 

By WILIAM HUNTER

A NASA probe is set to make history this Christmas Eve as it becomes the closest human-made object to the sun.

Tomorrow at 11:53 GMT, the Parker Solar Probe will pass within just 3.8 million miles (6.1 million km) of the sun's surface.

That is more than eight times closer than the distance between our home star and the nearest planet, Mercury.

As it reaches its closest point, the probe will also become the fastest human-made object ever made as it reaches a staggering 430,000 mph (692,000 kph).

In a moment that has been compared to the moon landing of 1969, Parker will 'touch' the sun's surface to gather vital data.

During that brief flyby, the probe will pass through the sun's super-hot outer atmosphere called the corona - the origin of solar storms which have the potential to cause chaos on Earth.

Although the Parker probe will endure temperatures exceeding 1,400 °C (2,550 °F) its near-indestructible heat shield should allow it to survive the extreme conditions. 

Nick Pinkine, Parker Solar Probe mission operations manager at the Johns Hopkins Applied Physics Laboratory (APL), says: 'No human-made object has ever passed this close to a star, so Parker will truly be returning data from uncharted territory.'

NASA's Parker Solar Probe (pictured) will make history on Christmas Eve as it becomes the closest human-made object to the sun 

The Parker Solar Probe was launched from Cape Canaveral in August 2018 before embarking on the 93 million-mile (149 million km) journey to the sun.

The goal was to gather more data about the sun's corona by flying as close as possible through the stellar atmosphere.

Because the gravitation pull is so strong at this distance, the probe needs to be moving incredibly fast to avoid slipping into the heart of the sun.

To do this, the probe has been repeatedly 'slingshot' around the sun and Venus, getting progressively faster with each pass.

In 2021, Parker made its first successful pass of the solar corona, dipping into a region where temperatures can reach over one million degrees Centigrade for up to five hours.

Since then, Parker has completed 21 solar slingshots, but tomorrow the probe will smash its own record for both speed and distance.

After completing its seventh loop around Venus in November, Parker is now using that 'gravity assist' to fly seven times closer to the star than any other spacecraft.

Passing at a distance of just 3.8 million miles (6.1 million km), Parker will gather particles from the corona inside a special instrument called the Solar Probe Cup.

The Parker probe will pass within 3.8 million miles (6.1 million km) of the sun's surface, moving at speeds of 30,000 mph (692,000 kph)

At the same time, Parker will surpass its previous speed record of 395,000 mph (635,000 kmph), according to NASA.

At its top speed, the probe will be moving 300 times faster than a Lockheed Martin F-16 fighter jet or 200 times faster than a rifle bullet.

Arik Posner, Parker Solar Probe program scientist for NASA, says: 'This is one example of NASA’s bold missions, doing something that no one else has ever done before to answer longstanding questions about our universe.'

In order to avoid melting during that time, the Parker Solar Probe has been designed to withstand unbelievably high temperatures.

The body of the probe itself is protected by a 2.4-metre (8ft) wide heat shield made of a type of carbon foam.

Although this shield is just 11cm (4.5 inches) thick, its material composition makes it almost indestructible.

Johns Hopkins APL explained in a mission briefing: 'One yard behind that, where the body of the spacecraft resides, it is almost room temperature.

'And all its systems will need to work perfectly for Parker to gather data from this dynamic environment near a star where no spacecraft has dared travel.'

As it passes, the probe will collect particles from the Sun in the 'Solar Probe Cup' (pictured) which is made of Titanium-Zirconium-Molybdenum, a metal alloy with a melting point of 2,349 °C (4,260 °F)

How frequent are superflares?

Meanwhile, the Solar Probe Cup is made of Titanium-Zirconium-Molybdenum, a metal alloy with a melting point of 2,349 °C (4,260 °F).

However, the probe's mission is about more than moving fast and withstanding high temperatures.

The data it brings back could make a huge difference in humanity's defences against devastating solar flares.

Thanks to the intense temperatures and powerful magnetic fields, scientists haven't been able to look inside the sun's corona.

However, this region is the origin of the plasma and magnetic fields which trigger solar flares and coronal mass ejections.

As the sun enters its solar maximum this year, scientists have warned that Earth is long overdue for an impact from a superflare which could cause widespread blackouts and damage to satellite networks.

By gathering data from this region, NASA says the Parker Solar Probe will help scientists make better predictions about space weather.

That could buy Earth valuable time to protect our most vulnerable systems in the event of a dangerous solar flare.

This data will help scientists understand what goes on within the sun's super-hot atmosphere. This could help us predict dangerous solar flares which have the potential to cause massive disruption on Earth (stock image)

Read More

• NASA sun probe becomes the fastest man-made object in history after traveling nearly 400,000mph over the solar surface 

Mr Posner says: 'We can’t wait to receive that first status update from the spacecraft and start receiving the science data in the coming weeks.'

Parker will transmit a beacon on Friday, December 27 to confirm it has survived the flyby with more data soon to follow.

The probe is then expected to make four more close flybys in 2025, but none so close as tomorrow.

And while the craft will eventually be torn apart by the sun's gravity, the heat shield could continue to orbit for thousands of years to come.

{ https://www.dailymail.co.uk/  }        

23-12-2024 om 21:16 geschreven door peter  

Huge 'Christmas Eve asteroid' the size of a 10-story building will skim past Earth at 14,743mph tonight, NASA warns

• READ MORE: Incredible moment asteroid crashes into Earth's atmosphere

By WILIAM HUNTER

With Christmas Eve just around the corner, many children might be hoping to spot Santa flying overhead.

But NASA has now warned that reindeer won't be the only things soaring above Earth in the coming days.

Tonight, a massive 'Chrismas Eve asteroid' the size of a ten-story building will skim past Earth at 14,743mph

According to NASA's Asteroid Watch dashboard, the space rock 2024 NX1 will reach its closest point to Earth at 02:56 am GMT in the early hours of Christmas Eve.

At an estimated size of 29 to 70 metres (95-230 ft) in diameter, scientists believe 2024 NX1 could hold the destructive potential of 12 million tonnes of TNT.

However, although this will be a 'near miss' by astronomical standards, experts say there is no chance of Christmas being ruined by a collision with this vast space rock.

The space agency estimates that the asteroid should pass by the planet harmlessly at a distance of about 4.48 million miles (7.21 million km).

Jess Lee, astronomer at the Royal Greenwich Observatory, told MailOnline: 'It will be very far away, around 18 times further away from the Earth than the Moon is, and so with this predicted path won’t come close enough to hit the Earth.'

NASA has warned that the huge 'Christmas Eve asteroid' will skim past Earth tonight at 14,743mph

(stock image) 

The Christmas Eve asteroid was only spotted on December 12 as NASA and the European Space Agency's (ESA) planetary defence systems noticed its approach.

After calculating its orbit, the agencies listed it as a 'close approach' - meaning that it is expected to pass within 4.65 million miles (7.5 million km) of Earth.

However, based on the size of the asteroid and its distance to Earth, the ESA only rates this as a 'very frequent' approach.

Nor has the ESA included 2024 XN1 on the 'Risk List' of objects with a non-zero probability of colliding with the planet.

This means that, despite passing within touching distance on the solar system scale, there is absolutely no chance of the Christmas Eve asteroid hitting Earth.

And while that is good news for Earth, at this distance the asteroid won't be visible even to an amateur astronomer using their own telescope. 

Yet, even for a relatively small asteroid the consequences of a potential impact would be devastating.

NASA's research suggests that an asteroid of 70m in diameter is capable of flattening an area of 700 square miles (2,000 square km) if it collided with the planet. 

The asteroid 2024 XN1 (pictured) is as big as a ten-story building and could be up to 70 metres (230 ft) according to the European Space Agency's estimates. The space agencies predict that the asteroid will reach its closest point in at 02:56 am GMT in the early hours of Christmas Eve

Ms Lee says: 'If you’d like to compare it to a previous asteroid impact, the Tunguska Event in Russia in 1908 involved an asteroid which was a roughly similar size to this one. 

'It exploded above the ground and knocked down 80 million trees. The energy comparison estimates have ranged from 3-30 megatons of TNT'

Thankfully, the Tunguska Event occurred over an unihabited region of Siberia but dangerous asteroid impacts have occurred in recent history. 

In 2013 a meteor just 20m in diameter exploded 28 miles (45km) above the Russian region of Chelyabinsk.

The resulting blast released the energy equivalent of around 440,000 tonnes of TNT, damaging thousands of buildings and injuring an estimated 1,600 people.

So, although the Christmas Eve asteroid has no risk of colliding with Earth, it is a stark reminder of just how close the planet comes to disaster on a fairly regular basis.  

After making its festive appearance next week, 2024 XN1 won't come near Earth again until January 2032.

During this pass the rock will come even closer, reaching a minimum distance of 3.1 million miles (4.7 million km).

At its closest point, the Christmas Eve asteroid will pass within 4.48 million miles (7.21 million km) of Earth. This is a near miss in astronomical terms but there is no risk of a collision 

However, the Christmas Eve asteroid will make its closest pass in December of 2106 when it will skim past Earth at a distance of just 2.11 million miles (3.4 million km).

2024 XN1 won't be the only space rock paying Earth a visit over the Christmas period.

Today, a small space rock named 2013 YB actually has a slim chance of slamming into Earth at 12:27 GMT. 

However, at less than 3m (10ft) in diameter, this rock is very likely to burn up in the atmosphere, producing nothing more dangerous than a particularly bright fireball.

At this size, NASA estimates that the asteroid would break up in the atmosphere more than 26 miles (43 km) above the ground, making it unlikely that any small fragments will make it to the ground.

Even the odds of that occurring are quite low, as ESA only predicts a one-in-52,356 chance of an impact.

On Christmas Day itself, an even larger asteroid named 2021 BA2 will make a remarkably close pass of Earth.

Based on its brightness, ESA estimates that this space rock could be between 30 to 70 (100-230 ft) metres in diameter - making it a potential 'city killer'.

Earth is constantly being passed by large space rocks, some of which (pictured) have a chance of colliding with the planet. If an asteroid the size of 2024 XN1 hit Earth it would explode with the energy of 12 million tonnes of TNT

At 21:19 pm GMT on Christmas Day, 2021 BA2 will hit its closest point to Earth, passing by at just 1.71 million miles (2.76 million km).

But at more than seven times the distance to the moon, space agencies predict no risk of a collision between the asteroid and the planet.

The next truly large asteroid to pass by Earth won't be until January 5, 2025, when a 400m (1,310 ft) asteroid will make a close pass of the planet.

This Eiffel Tower-sized space rock will blast past Earth at 49,660 miles per hour (79,920 kmph), reaching its closest point just 2.29 million miles (3.68 million km) from Earth.

VIDEOS

{ https://www.dailymail.co.uk/ }

23-12-2024 om 20:34 geschreven door peter  

The position of the magnetic north pole is officially changing. Why?

Why does Earth have a magnetic field?

Earth's main magnetic field is generated in the planet's outer core, a layer of molten iron 2,2001,800-3,100 miles (2,890-5,000 kilometers) below the planet's surface. The electrically conductive liquid iron is in constant motion, and when it moves through an existing weak magnetic field, that motion produces an electric current. The electric current in turn generates its own magnetic field, leading to a self-sustaining process known as the geodynamo.

Related: 

• Earth's rotating inner core is starting to slow down — and it could alter the length of our days

The geodynamo has continually regenerated Earth's magnetic field for billions of years. Without something to sustain the field, Earth would have lost its magnetic field after about 40,000 years, said Bruce Buffett, a geophysicist at the University of California, Berkeley.

"If you had a hot cannonball and you put it on the table, it would gradually cool. [The heat] would diffuse away and essentially go back to ambient," Buffett told Live Science. "The same is true with the magnetic field. If you're not sustaining it by these fluid motions, it will gradually decay away and disappear."

Where is the magnetic north pole?

The magnetic north pole is different from the geographic North Pole, which is always stationary. The geographic North Pole is the point where Earth's axis of rotation meets the planet's surface and where all lines of longitude converge. The magnetic north pole, meanwhile, is the point in the Northern Hemisphere where Earth's magnetic field lines point directly into the planet.

The complex motion of the outer core causes the magnetic north pole to shift tens of miles per year. Because Earth's magnetic field is slightly asymmetrical and more complex than that of a regular bar magnet, the magnetic south pole — the point in the Southern Hemisphere where the magnetic field points straight into the planet — doesn't move in quite the same way. But changes in the strength of the magnetic field near the North Pole have caused it to shift from the Canadian Arctic toward Siberia in recent years.

What is the World Magnetic Model?

The World Magnetic Model is a mathematical model of Earth's magnetic field and a prediction for how the field will evolve over the next several years. The model combines data from satellites such as the European Space Agency's Swarm mission and from high-precision magnetometers at ground-based observatories to predict the magnetic field at each point on Earth.

Navigation apps use the World Magnetic Model along with GPS to orient users. "Your smartphone or GPS system has a magnetometer, effectively a digital compass built into it," said William Brown, a BGS geophysicist who helped create and update the World Magnetic Model. "It measures the direction of the magnetic field where you are, and it enters your position into the World Magnetic Model software to tell it what the magnetic field should look like. And then, by comparing what I measured and what I should have got, you can work out which direction you're facing."

Why is the World Magnetic Model being updated now?

A new version of the World Magnetic Model is released every five years to account for changes in the magnetic field from the motion of the outer core. This latest update is part of that five-year schedule.

"The real challenge is, and the reason why we release a model every five years, it doesn't change in a regular way. It's not completely predictable. It's a really complicated, chaotic system," Brown told Live Science. "Typically, about five years is when the accuracy of the model starts to get to the point where it's not as good as we would like it. So we make a better prediction with five years more information to work from, and just update the prediction going forward."

Small deviations from the predicted field can accumulate over time and occasionally compound to the point where the model must be updated more frequently. For example, the NCEI and BGS released an off-cycle update in 2019 to account for the outer core flowing faster than usual in the Northern Hemisphere — a phenomenon that caused the magnetic north pole to shift much more quickly than usual.

But for most people, the 2025 update won't result in any noticeable changes to navigation, and users won't have to change anything for phone map apps to work properly.

"You should be able to navigate as well as you could yesterday," Brown said. "We keep the updates coming so that it's only a bit of time, small enough that most people don't notice, because for most users, the accuracy is more than they need anyway."

{ https://www.livescience.com/ }

23-12-2024 om 00:32 geschreven door peter  

{ https://www.universetoday.com/ }

22-12-2024 om 21:51 geschreven door peter  

In addition, it can also cause equipment to overheat as it coats thermal radiators and accumulates on windows, camera lenses, and visors, making it harder to see, navigate, and acquire accurate images. Kristen John, the Lunar Surface Innovation Initiative technical integration lead at NASA’s Johnson Space Center, said in a NASA press release: “The fine grain nature of dust contains particles that are smaller than the human eye can see, which can make a contaminated surface appear to look clean.”

Addressing the Problem

These technologies were developed by NASA’s Game Changing Development program within the agency’s Space Technology Mission Directorate (STMD). The “Lunar Gravity Simulation via Suborbital Rocket” flight test will study regolith mechanics and lunar dust transport in a simulated lunar gravity environment. The payload includes projects for mitigating and cleaning dust using multiple strategies. They include:

ClothBot:
This compact robot is designed to simulate and measure how dust behaves in a pressurized environment, which astronauts could bring back after conducting Extravehicular Activities (EVAs). The robot relies on pre-programmed motions that simulate astronauts’ movements when removing their spacesuits (aka “doffing”), releasing a small dose of lunar regolith simulant. A laser-illuminated imaging system will then capture the dust flow in real-time while sensors record the size and number of particles.

Electrostatic Dust Lofting (EDL):
The EDL will examine how lunar dust is “lofted” (kicked up) when it becomes electrostatically charged to improve models on dust lofting. During the lunar gravity phase of the flight, a dust sample will be released that the EDL will illuminate using a UV light source, causing the particles to become charged. The dust will then pass through a sheet laser as it rises from the surface while the EDL observes and records the results. The EDL’s camera will continue to record the dust until the mission ends, even after the lunar gravity phase ends and the UV light is shut off.

Hermes Lunar-G:
The Hermes Lunar-G project, developed by NASA, Texas A&M, and Texas Space Technology Applications and Research (T-STAR), is based on a facility (Hermes) that previously operated on the International Space Station (ISS). Like its predecessor, the Lunar-G project will rely on repurposed Hermes hardware to study lunar regolith simulants. This will be done using four canisters containing compressed lunar dust simulants. When the flight enters its lunar gravity phase, these simulants will decompress and float around in the canisters while high-speed cameras and sensors capture data. The results will be compared to microgravity data from the ISS and similar flight experiments.

Dust Mitigation Strategies

The data obtained by these projects will provide information on regolith generation rates, transport, and mechanics that will help scientists refine computational models. This will allow mission planners and designers to develop better strategies for dust mitigation for future missions to the Moon and Mars. Already, this challenge informs several aspects of NASA’s technological developments, ranging from In-Situ Resource Utilization (ISRU) and construction to transportation and surface power. Said John:

“Learning some of the fundamental properties of how lunar dust behaves and how lunar dust impacts systems has implications far beyond dust mitigation and environments. Advancing our understanding of the behavior of lunar dust and advancing our dust mitigation technologies benefits most capabilities planned for use on the lunar surface.”

The test flight and vehicle enhancements that will enable the simulation of lunar gravity are being funded through NASA’s Flight Opportunities program.

Further Reading: 

• NASA

{ https://www.universetoday.com/ }

22-12-2024 om 21:25 geschreven door peter  

Carbon Dioxide Ice Turns Martian Polar Region White

Planetary scientists using the High Resolution Stereo Camera on ESA’s Mars Express spacecraft have captured stunning images of an enigmatic landscape in the Australe Scopuli region of the Red Planet’s southern hemisphere.

Frosty scene in the Australe Scopuli region at the south pole of Mars.

Image credit: ESA / DLR / FU Berlin.

“Here, swirls of carbon dioxide ice and dust layers wrap around the scene, turning the Red Planet white,” the ESA researchers said in a statement.

“The contrasting light and dark layers are particularly striking in the exposed faces of hills and valleys.”

An artist's interpretation of an ice-covered river sourced from meltwater beneath Mars’ south polar cap.

Credit: Peter Buhler/PSI

“They trace out the distinctive seasonal polar layered deposits characteristic of this region, formed as layers of ice freeze with varying amounts of dust trapped within.”

“Perhaps you’d prefer a sleigh ride, but either way dress warm, because it’s cold outside: minus 125 degrees Celsius (minus 193 degrees Fahrenheit),” they added.

“Any Martian skier or sleigh rider would also need to slalom around hundreds of potential dust jets.”

“That’s because ski season is almost over and it’s beginning to look a lot like spring — or even summer, for this image was taken on June 16, 2022, close to summer solstice at the south pole.”

Zooming into the image above reveals numerous dark patches where the ice has already sublimated away, a sure sign that the Sun’s warming rays have been falling on this region for some time.

“When sunlight shines through the translucent top layers of the carbon dioxide ice it warms up the underlying surface,” the scientists explained.

“The ice at the bottom of the layer begins to sublimate, creating pockets of trapped gas.”

“The pressure builds up until the overlying ice suddenly cracks, resulting in a burst of gas jetting through the surface.”

“These gas fountains carry dark dust from below, which falls back to the surface in a fan-shaped pattern moulded by the direction of the prevailing wind.”

“The fans can range in length from tens to hundreds of meters.”

“An even closer look shows that the fans often appear to follow the boundaries between the polar layered deposits.”

“Presumably these boundaries represent zones of weakness, where the escaping dust-laden jets can break through the ice layers more easily.”

“We may well have missed our chance to make ‘Frosty the Snowman’, but it’s still a wonderful time of year on Mars.”

{ https://www.sci.news/ }

22-12-2024 om 00:52 geschreven door peter  

Earth's magnetic North Pole is shifting toward Russia. What does that mean?

Fernando Cervantes Jr.   USA TODAY

World Magnetic Model

The Earth's magnetic North Pole is currently moving toward Russia in a way that British scientists have not seen before.

Scientists have been tracking the magnetic North Pole for centuries, telling the British newspaper The Times that it had moved closer to the northern coast of Canada. In the 1990s, it drifted into the Atlantic before moving in a faster manner toward Siberia in Russia.

Compass needles in the Northern Hemisphere point toward the magnetic North Pole, although the exact location of it changes from time to time as the contours of Earth’s magnetic field also change. The magnetic North Pole is sometimes confused with the geographic North Pole, but this spot stays at the same place as it is where all lines of longitude converge.

In the 300 years between 1600 and 1900, scientists estimate that the magnetic North Pole moved about six miles per year. At the beginning of this century, it picked up to about 34 miles per year, before slowing in the last five years to about 22 miles per year.

Magnetic north has shifted a lot over the centuries.

(BGS)

Why does the North Pole's movement matter?

The moves are tracked as the data allows the compasses in our smartphones and other navigation devices to navigate.

Scientists told The Times these movements are tracked by the British Geological Survey and the U.S. National Oceanic and Atmospheric Administration. In conjunction, they make the World Magnetic Model, that predicts where the pole should be at any time.

The model plays a role in the GPS systems we use on a day-to-day basis.

“Planes, boats, submarines, you name it, it’s in there,” William Brown, the global geomagnetic field modeler at the British Geological Survey, said in an interview with The Times.

It's time to recalibrate the navigation systems on ships, airplanes, and (given the time of year) Santa's sleigh: the position of the magnetic North Pole is officially being changed, continuing its shift away from Canada and towards Siberia.

Experts from the US National Oceanic and Atmospheric Administration (NOAA) and the British Geological Survey (BGS) have joined forces – as they do every five years – to produce a new, more accurate World Magnetic Model (WMM).

While the geographical North Pole stays fixed in place (at the very summit of the Earth's rotational axis), the WMM pinpoints the magnetic North Pole – where Earth's magnetic field points straight down, a perfectly vertical magnetic field.

And as the iron and nickel inside our planet shift, so does Earth's magnetic field, meaning the North (and South) Poles are also constantly on the move. If you're using a compass or a GPS system, knowing exactly where these points are is crucial.

"The current behaviour of magnetic north is something that we have never observed before," says global geomagnetic field modeller William Brown, from BGS.

"Magnetic north has been moving slowly around Canada since the 1500s but, in the past 20 years, it accelerated towards Siberia, increasing in speed every year until about five years ago, when it suddenly decelerated from 50 to 35 kilometers [31 to 22 miles] per year, which is the biggest deceleration in speed we've ever seen."

Research suggests that two giant magnetic lobes – one under Canada and one under Siberia – are what's driving the shifting of magnetic north. Sometimes the shifts are dramatic enough that an emergency update is required, outside of the usual 5-year cycle.

Now we have a more accurate map of magnetic north, one that should be good for another half a decade. For the first time, a higher resolution map is also available, which offers more than 10 times more detail: it has a spatial resolution of about 300 km at the equator compared to the standard 3,300 km.

The 2025 World Magnetic Model. (NOAA/NCEI)

What causes the movements?

Earth’s outer core is made up of mostly molten iron, a liquid metal. Unpredictable changes in the way it flows cause the magnetic field around the Earth to shift, which then causes the magnetic core to also move.

“It’s like a giant cup of tea,” Brown said to The Times. “It’s a hot liquid with the viscosity of water.”

• Fernando Cervantes Jr. is a trending news reporter for USA TODAY. Reach him at fernando.cervantes@gannett.com and follow him on X @fern_cerv_.

The magnetic North Pole was first discovered by Sir James Clark Ross in northern Canada back in 1831.

Since then, researchers have gradually been able to track it with more precision, using ground measurements taken all across the globe as well as readings from satellites in space.

{ https://eu.usatoday.com/news/ }

22-12-2024 om 00:00 geschreven door peter  

Earth's magnetic North Pole is shifting toward Russia. What does that mean?

Fernando Cervantes Jr.   USA TODAY

World Magnetic Model

The Earth's magnetic North Pole is currently moving toward Russia in a way that British scientists have not seen before.

Scientists have been tracking the magnetic North Pole for centuries, telling the British newspaper The Times that it had moved closer to the northern coast of Canada. In the 1990s, it drifted into the Atlantic before moving in a faster manner toward Siberia in Russia.

Compass needles in the Northern Hemisphere point toward the magnetic North Pole, although the exact location of it changes from time to time as the contours of Earth’s magnetic field also change. The magnetic North Pole is sometimes confused with the geographic North Pole, but this spot stays at the same place as it is where all lines of longitude converge.

In the 300 years between 1600 and 1900, scientists estimate that the magnetic North Pole moved about six miles per year. At the beginning of this century, it picked up to about 34 miles per year, before slowing in the last five years to about 22 miles per year.

Magnetic north has shifted a lot over the centuries.

(BGS)

Why does the North Pole's movement matter?

The moves are tracked as the data allows the compasses in our smartphones and other navigation devices to navigate.

Scientists told The Times these movements are tracked by the British Geological Survey and the U.S. National Oceanic and Atmospheric Administration. In conjunction, they make the World Magnetic Model, that predicts where the pole should be at any time.

The model plays a role in the GPS systems we use on a day-to-day basis.

“Planes, boats, submarines, you name it, it’s in there,” William Brown, the global geomagnetic field modeler at the British Geological Survey, said in an interview with The Times.

It's time to recalibrate the navigation systems on ships, airplanes, and (given the time of year) Santa's sleigh: the position of the magnetic North Pole is officially being changed, continuing its shift away from Canada and towards Siberia.

Experts from the US National Oceanic and Atmospheric Administration (NOAA) and the British Geological Survey (BGS) have joined forces – as they do every five years – to produce a new, more accurate World Magnetic Model (WMM).

While the geographical North Pole stays fixed in place (at the very summit of the Earth's rotational axis), the WMM pinpoints the magnetic North Pole – where Earth's magnetic field points straight down, a perfectly vertical magnetic field.

And as the iron and nickel inside our planet shift, so does Earth's magnetic field, meaning the North (and South) Poles are also constantly on the move. If you're using a compass or a GPS system, knowing exactly where these points are is crucial.

"The current behaviour of magnetic north is something that we have never observed before," says global geomagnetic field modeller William Brown, from BGS.

"Magnetic north has been moving slowly around Canada since the 1500s but, in the past 20 years, it accelerated towards Siberia, increasing in speed every year until about five years ago, when it suddenly decelerated from 50 to 35 kilometers [31 to 22 miles] per year, which is the biggest deceleration in speed we've ever seen."

Research suggests that two giant magnetic lobes – one under Canada and one under Siberia – are what's driving the shifting of magnetic north. Sometimes the shifts are dramatic enough that an emergency update is required, outside of the usual 5-year cycle.

Now we have a more accurate map of magnetic north, one that should be good for another half a decade. For the first time, a higher resolution map is also available, which offers more than 10 times more detail: it has a spatial resolution of about 300 km at the equator compared to the standard 3,300 km.

The 2025 World Magnetic Model. (NOAA/NCEI)

What causes the movements?

Earth’s outer core is made up of mostly molten iron, a liquid metal. Unpredictable changes in the way it flows cause the magnetic field around the Earth to shift, which then causes the magnetic core to also move.

“It’s like a giant cup of tea,” Brown said to The Times. “It’s a hot liquid with the viscosity of water.”

• Fernando Cervantes Jr. is a trending news reporter for USA TODAY. Reach him at fernando.cervantes@gannett.com and follow him on X @fern_cerv_.

The magnetic North Pole was first discovered by Sir James Clark Ross in northern Canada back in 1831.

Since then, researchers have gradually been able to track it with more precision, using ground measurements taken all across the globe as well as readings from satellites in space.

{ https://eu.usatoday.com/news/ }

22-12-2024 om 00:00 geschreven door peter  

Huge 'Christmas Eve asteroid' the size of a 10-storey building will skim past Earth at 14,743mph on 24 December, NASA warns

• READ MORE: Scientists come up with a way to save Earth from asteroid collision

By WILIAM HUNTER

This Christmas Eve, children around the world may be hoping to catch a glimpse of Santa's sleigh flying through the skies.

But NASA has warned that jolly Old Saint Nick won't be the only thing whizzing over our heads this December 24.

A massive 'Christmas Eve asteroid' the size of a 10-story building will skim past Earth at 14,743mph.

According to NASA's Asteroid Watch dashboard, asteroid 2024 XN1 should pass by harmlessly at a distance of 4.48 million miles (7.21 million km) from Earth.#

Although this will be a near miss by astronomical standards, experts say there is no chance of Christmas being ruined by a collision with this vast space rock. 

Jess Lee, astronomer at the Royal Greenwich Observatory, told MailOnline: 'It will be very far away, around 18 times further away from the Earth than the Moon is, and so with this predicted path won’t come close enough to hit the Earth.'

But at an estimated size of 29 to 70 metres (95-230 ft) in diameter, this is a stark reminder of just how close Earth can get to a deadly encounter.

If 2024 XN1 were to hit the planet, scientists estimate that it would impact with a force equivalent to 12 million tonnes of TNT and flatten an area of 700 square miles (2,000 square km).

NASA has warned that the huge 'Christmas Eve asteroid' will skim past Earth on December 24 at 14,743mph

(stock image) 

The Christmas Eve asteroid was only spotted on December 12 as NASA and the European Space Agency's (ESA) planetary defence systems noticed its approach.

After calculating its orbit, the agencies listed it as a 'close approach' - meaning that it is expected to pass within 4.65 million miles (7.5 million km) of Earth.

2024 XN1 will reach its closest point to Earth at 02:56 am GMT on the morning of Christmas Eve.

However, based on the size of the asteroid and its distance to Earth, the ESA only rates this as a 'very frequent' approach.

Nor has the ESA included 2024 XN1 on the 'Risk List' of objects with a non-zero probability of colliding with the planet.

This means that, despite passing within touching distance on the solar system scale, there is absolutely no chance of the Christmas Eve asteroid hitting Earth.

And while that is good news for Earth, at this distance the asteroid won't be visible even to an amateur astronomer using their own telescope. 

Yet, even for a relatively small asteroid the consequences of a potential impact would be devastating.

The asteroid 2024 XN1 (pictured) is as big as a ten-story building and could be up to 70 metres (230 ft) according to the European Space Agency's estimates 

At its closest point, the Christmas Eve asteroid will pass within 4.48 million miles (7.21 million km) of Earth. This is a near miss in astronomical terms but there is no risk of a collision 

Ms Lee says: 'If you’d like to compare it to a previous asteroid impact, the Tunguska Event in Russia in 1908 involved an asteroid which was a roughly similar size to this one. 

'It exploded above the ground and knocked down 80 million trees. The energy comparison estimates have ranged from 3-30 megatons of TNT'

After making its festive appearance next week, 2024 XN1 won't come near Earth again until January 2032.

During this pass the rock will come even closer, reaching a minimum distance of 3.1 million miles (4.7 million km).

However, the Christmas Eve asteroid will make its closest pass in December of 2106 when it will skim past Earth at a distance of just 2.11 million miles (3.4 million km).

2024 XN1 won't be the only space rock paying Earth a visit over the Christmas period.

On December 23, a small space rock named 2013 YB actually has a slim chance of slamming into Earth.

However, at less than 3m (10ft) in diameter, this rock is very likely to burn up in the atmosphere, producing nothing more dangerous than a particularly bright fireball.

Earth is constantly being passed by large space rocks, some of which (pictured) have a chance of colliding with the planet. If an asteroid the size of 2024 XN1 hit Earth it would explode with the energy of 12 million tonnes of TNT

Even the odds of that occurring are quite low as ESA only predicts a one in 52,356 chance of an impact.

On Christmas Day itself, an even larger asteroid named 2021 BA2 will make a remarkably close pass of Earth.

Based on its brightness, ESA estimates that this space rock could be between 30 to 70 (100-230 ft) metres in diameter - making it a potential 'city killer'.

At 21:19 pm GMT on Christmas Day, 2021 BA2 will hit its closest point to Earth, passing by at just 1.71 million miles (2.76 million km).

But at more than seven times the distance to the moon, space agencies predict no risk of a collision between the asteroid and the planet.

The next truly large asteroid to pass by Earth won't be until January 5, 2025, when a 400m (1,310 ft) asteroid will make a close pass of the planet.

This Eiffel Tower-sized space rock will blast past Earth at 49,660 miles per hour (79,920 kmph), reaching its closest point just 2.29 million miles (3.68 million km) from Earth.

{ https://www.dailymail.co.uk/ }

21-12-2024 om 23:55 geschreven door peter  

• READ MORE: China's 'floating' hyperloop train begins construction of new line

By JONATHAN CHADWICK FOR MAILONLINE 

It's been more than 20 years since the legendary Concorde last flew, but China could be the one to provide its spiritual successor. 

A Beijing-based company called Space Transportation is working on a supersonic jet that's even faster than NASA's 'Son of Concorde'. 

In tests, the jet's engine reached Mach 4 or 3,045mph – four times the speed of sound – at altitudes of more than 65,600 feet, reports South China Morning Post. 

This is twice as fast as the defunct Concorde's max speeds (Mach 2 or 1,338mph) and three times that of NASA's 'Son of Concorde' (937 miles per hour). 

'This engine has significant commercial potential in the field of high-speed flight within near-space environments,' Space Transportation said in a statement. 

The successful test flight is a key milestone for developing the Yunxing supersonic civilian jet, which will fly passengers from London to New York in under 2 hours.

Space Transportation aims to have the aircraft ready for its first flight by 2027 and the first commercial high-speed point-to-point transport flight to take place by 2030.  

Yunxing passengers will be high enough to see the curvature of Earth – where the horizon is a slight curve rather than a straight line, normally seen from 50,000 feet. 

The jet reached Mach 4 or 3,045mph - four times the speed of sound - at altitudes of more than 65,600 feet

Called Jindouyun, the jet engine reached Mach 4 or 3,045mph - four times the speed of sound - at altitudes of more than 65,600 feet

Jindouyun, or JinDou400, was named after the 'somersault cloud' used by the Monkey King in the classic Chinese novel 'Journey to the West'. 

On Tuesday (December 17) it completed its test flight in northwestern China, reports Global Times, the daily tabloid owned by the Chinese Communist Party.

Jindouyun is a 'ramjet' – a type of 'airbreathing' jet engine that uses the engine's forward motion to compress the incoming air. 

Ramjet engines burn oxygen directly from the atmosphere, rather than needing to carry their own supply, making them a low-cost, high-power option. 

'This test flight provided key performance data on the engine, validating critical systems including the fuel supply, electrical and control systems,' the firm said.

'It also confirmed the engine's stability and reliability, marking a major milestone in its development from a prototype to a fully functional product.'

Powering the Yunxing aircraft, the Jindouyun engine could usher a new era of superfast passenger travel for commuters and holiday-makers alike. 

Promo images suggest Yunxing will be a sleek and futuristic vessel, more like something from Thunderbirds than what we're used to seeing at airports. 

The successful test flight is a key milestone for developing the Yunxing supersonic civilian jet, which will fly passengers from London to New York in under 2 hours

Powering the Yunxing aircraft, the Jindouyun engine could usher a new era of superfast passenger travel for commuters and holiday-makers alike

Space Transportation aims to have the aircraft ready for its first flight by 2027 and the first commercial high-speed point-to-point transport flight to take place by 2030. Pictured, the firm's promo 

Yunxing is now a serious rival for NASA in the race to fly paying passengers aboard a supersonic jet for the first time since Concorde

The plane will be made of lightweight, high-strength composite materials, designed to withstand extreme aerodynamic heating while travelling at Mach 4. 

Unlike traditional planes that build speed horizontally for takeoff, Yunxing will perform vertical takeoffs and landings, allowing it to ascend and descend in tighter spaces.

This means it won't have to use conventional runways at today's airports, potentially operating from smaller, urban airport facilities instead. 

Yunxing is now a serious rival for NASA in the race to fly paying passengers aboard a supersonic jet for the first time since Concorde.

After years of anticipation, NASA finally unveiled its supersonic X-59 plane aircraft, unofficially dubbed 'Son of Concorde', back in January. 

Developed for NASA by Lockheed Martin, the $247.5 million X-59 plane is capable of cruising at 937 miles per hour – faster than the speed of sound but not anywhere near Mach 4. 

However, because of its more modest supersonic speeds, X-59 may be a more realistic contender for passenger travel in the near-term compared with other experimental vehicles in development

If cleared for commercial travel, it could be used by flight operators and take passengers from London to New York in under four hours – still slashing today's travel time in half. 

The X-59's thin, tapered nose accounts for almost a third of its length and will break up the shock waves that would ordinarily result in a supersonic aircraft causing a sonic boom

Meanwhile, another American company called Boom Supersonic is working on its own supersonic craft, called Overture, which is eyeing commercial passenger flights in 2029. 

Last year, a scaled-down prototype of Overture, called XB-1 Baby Boom, has completed 'key milestones' during testing as it progresses towards its first flight. 

As for Concorde, the legendary Anglo-French creation had its first commercial flights in 1976, but it was grounded in October 2003 in the aftermath of the catastrophic Air France Flight 4590 crash. 

Other reasons for the demise of Concorde were high fuel costs, concern over its noise and a preference for lower fares over speed. 

No government or manufacturer has since been able to build a commercial plane that can travel faster than the speed of sound.

THE HISTORY OF CONCORDE 

Concorde was a turbojet-powered supersonic passenger jet that was operated from 1976 until 2003.

It had a maximum speed over twice the speed of sound at Mach 2.04 (1,354mph or 2,180k per hour at cruise altitude) and could seat 92 to 128 passengers.

It was first flown in 1969, but needed further tests to establish it as viable as a commercial aircraft. Concorde entered service in 1976.

Concorde was the world's first supersonic airliner and operated for 27 years, but it was grounded in October 2003. Pictured is British Airways Concorde G-BOAB taking off with its landing gear still extended over the Cotswolds town of Fairford, Gloucestershire on July 20, 1996, during the annual RAF Fairford airshow

It is one of only two supersonic transports to have been operated commercially. The other is the Soviet-built Tupolev Tu-144, which ran as a passenger aircraft only for a few years in the 1970s due to safety issues.

Concorde was jointly developed and manufactured by Aérospatiale and the British Aircraft Corporation (BAC) under an Anglo-French treaty. Concorde's name, meaning harmony or union, reflected the cooperation on the project between the UK and France.   

Concorde was retired in 2003 due to a general downturn in the commercial aviation industry after its only crash in 2000, the September 11 attacks in 2001, and a decision by Airbus, the successor to Aérospatiale and BAC, to discontinue maintenance support. 

{ https://www.dailymail.co.uk/ }

21-12-2024 om 21:00 geschreven door peter  

China puts models of its future crewed moon landing spacecraft on display (video)

19-12-2024 om 23:29 geschreven door peter  

The study was led by Ryan Park, a Senior Research Scientist and Principal Engineer at NASA’s Jet Propulsion Laboratory (JPL). He was joined by multiple colleagues from NASA JPL, the Centro Interdipartimentale di Ricerca Industriale Aerospaziale (CIRI) at the Università di Bologna, the National Institute for Astrophysics (NIAF), the Sapienza Università di Roma, the Southwest Research Institute (SwRI), and NASA’s Goddard Space Flight Center, and multiple universities. Their findings were described in a paper that appeared in the journal Nature.

As they explain in their paper, two types of analysis have predicted the existence of a global magma ocean. On the one hand, magnetic induction measurements conducted by the Galileo mission suggested the existence of a magma ocean within Io, approximately 50 km [~30 mi] thick and located near the surface. These results also implied that about 20% of the material in Io’s mantle is melted. However, these results were subjected to debate for many years. In recent years, NASA’s Juno mission conducted multiple flybys of Io and the other Jovian moons and obtained data that supported this conclusion.

In particular, the Juno probe conducted a global mapping campaign of Io’s volcanoes, which suggested that the distribution of volcanic heat flow is consistent with the presence of a global magma ocean. However, these discoveries have led to considerable debate about these techniques and whether they can be used to distinguish whether a shallow global magma ocean drives Io’s volcanic activity. This is the question Park and his colleagues sought to address in their study:

“In our study, Io’s tidal deformation is modeled using the gravitational tidal Love number k₂, which is defined as the ratio of the imposed gravitational potential from Jupiter to the induced potential from the deformation of Io. In short, if k₂ is large, there is a global magma ocean, and if k₂ is small, there is no global magma ocean. Our result shows that the recovered value of k₂ is small, consistent with Io not having a global magma ocean.”

The significance of these findings goes far beyond the study of Io and other potentially volcanic moons. Beyond the Solar System, astronomers have discovered countless bodies that (according to current planetary models) experience intense tidal heating. This includes rocky exoplanets that are several times the size and mass of Earth (Super-Earths) and in the case of tidally-locked planets like the TRAPPIST-1 system. These findings are also relevant for the study of exomoons that also experience intense tidal heating (similar to the Jovian moons). As Park explained:

“Although it is commonly assumed among the exoplanet community that intense tidal heating may lead to magma oceans, the example of Io shows that this need not be the case. Our results indicate that tidal forces do not universally create global magma oceans, which may be prevented from forming due to rapid melt ascent, intrusion, and eruption, so even strong tidal heating – like that expected on several known exoplanets and super-Earths – may not guarantee the formation of magma oceans on moons or planetary bodies.”

Further Reading: 

• Nature

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19-12-2024 om 18:34 geschreven door peter  

Posted by Evan Gough

The JWST Looked Over the Hubble’s Shoulder and Confirmed that the Universe is Expanding Faster

It’s axiomatic that the Universe is expanding. However, the rate of expansion hasn’t remained the same. It appears that the Universe is expanding more quickly now than it did in the past.

Astronomers have struggled to understand this and have wondered if the apparent acceleration is due to instrument errors. The JWST has put that question to rest.

American astronomer Edwin Hubble is widely credited with discovering the expansion of the Universe. But it actually stemmed from relativity equations and was pioneered by Russian scientist Alexander Freedman. Hubble’s Law bears Edwin’s name, though, and he was the one who confirmed the expansion, called Hubble’s constant, and put a more precise value to it. It measures how rapidly galaxies that aren’t gravitationally bound are moving away from one another. The movement of objects due solely to the Hubble constant is called the Hubble flow.

Measuring the Hubble constant means measuring distances to far-flung objects. Astronomers use the cosmic distance ladder (CDL) to do that. However, the ladder has a problem.

The first rungs on the CDL are fundamental measurements that can be observed directly. Parallax measurement is the most important fundamental measurement. But the method breaks down at great distances.

Beyond that, astronomers use standard candles, things with known intrinsic brightness, like supernovae and Cepheid variables. Those objects and their relationships help astronomers measure distances to other galaxies. This has been tricky to measure, though advancing technology has made progress.

Another pair of problems plagues the effort, though. The first is that different telescopes and methods produce different distance measurements. The second is that our measurements of distances and expansion don’t match up with the Standard Model of Cosmology, also known as the Lambda Cold Dark Matter (LCDM) model. That discrepancy is called the Hubble tension.

The question is, can the mismatch between the measurements and the LCDM be explained by instrument differences? That possibility has to be eliminated, and the trick is to take one large set of distance measurements from one telescope and compare them to another.

New research in The Astrophysical Journal tackles the problem by comparing Hubble Space Telescope measurements with JWST measurements. It’s titled “JWST Validates HST Distance Measurements: Selection of Supernova Subsample Explains Differences in JWST Estimates of Local H₀.” The lead author is Adam Riess, a Bloomberg Distinguished Professor and Thomas J. Barber Professor of Physics and Astronomy at Johns Hopkins University. Riess is also a Nobel laureate, winning the 2011 Nobel Prize in Physics “for the discovery of the accelerating expansion of the Universe through observations of distant supernovae,” according to the Nobel Institute.

As of 2022, the Hubble Space Telescope gathered the most numerous sample of homogeneously measured standard candles. It measured a large number of standard candles out to about 40 Mpc or about 130 million light-years. “As of 2022, the largest collection of homogeneously measured SNe Ia is complete to D less than or equal to 40 Mpc or redshift z less than or equal to 0.01,” the authors of the research write. “It consists of 42 SNe Ia in 37 host galaxies calibrated with observations of Cepheids with the Hubble Space Telescope (HST), the heritage of more than 1000 orbits (a comparable number of hours) invested over the last ~20 yrs.”

In this research, the astronomers used the powerful JWST to cross-check the Hubble’s work. “We cross-check the Hubble Space Telescope (HST) Cepheid/Type Ia supernova (SN Ia) distance ladder, which yields the most precise local H₀ (Hubble flow), against early James Webb Space Telescope (JWST) subsamples (~1/4 of the HST sample) from SH0ES and CCHP, calibrated only with NGC 4258,” the authors write. SH0ES and CCHP are different observing efforts aimed at measuring the Hubble constant. SH0ES stands for Supernova H0 for the Equation of State of Dark Energy, and CCHP stands for Chicago-Carnegie Hubble Program, which uses the JWST to measure the Hubble constant.

“JWST has certain distinct advantages (and some disadvantages) compared to HST for measuring distances to nearby galaxies,” Riess and his co-authors write. It offers a 2.5 times higher near-infrared resolution than the HST. Despite some of its disadvantages, the JWST “is able to provide a strong cross-check of distances in the first two rungs,” the authors explain.

Observations from both telescopes are closely aligned, which basically minimizes instrument error as the cause of the discrepancy between observations and the Lambda CDM model.

“While it will still take multiple years for the JWST sample of SN hosts to be as large as the HST sample, we show that the current JWST measurements have already ruled out systematic biases from the first rungs of the distance ladder at a much smaller level than the Hubble tension,” the authors write.

This research covered about one-third of the Hubble’s data set, with the known distance to a galaxy called NGC 4258 serving as a reference point. Even though the data set was small, Riess and his co-researchers achieved impressively precise results. They showed that the measurement differences were less than 2%. That’s much less than the 8% to 9% in the Hubble tension discrepancy.

That means that our Lamda CDM model is missing something. The standard model yields an expansion rate of about 67 to 68 kilometres per second per megaparsec. Telescope observations yield a slightly higher rate: between 70 and 76 kilometres per second per megaparsec. This work shows that the discrepancy can’t be due to the different telescopes and methods.

“The discrepancy between the observed expansion rate of the universe and the predictions of the standard model suggests that our understanding of the universe may be incomplete. With two NASA flagship telescopes now confirming each other’s findings, we must take this [Hubble tension] problem very seriously—it’s a challenge but also an incredible opportunity to learn more about our universe,” said lead author Riess.

What could be missing from the Lambda CDM model?

Marc Kamionkowski is a Johns Hopkins cosmologist who helped calculate the Hubble constant and recently developed a possible new explanation for the tension. Though not part of this research, he commented on it in a press release.

“One possible explanation for the Hubble tension would be if there was something missing in our understanding of the early universe, such as a new component of matter—early dark energy—that gave the universe an unexpected kick after the big bang,” said Kamionkowski. “And there are other ideas, like funny dark matter properties, exotic particles, changing electron mass, or primordial magnetic fields that may do the trick. Theorists have license to get pretty creative.”

The door is open, theorists just have to walk in.

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19-12-2024 om 18:11 geschreven door peter