NASA benadrukt dat astronauten Starliner niet geblokkeerd zitten in ISS

NASA benadrukt dat astronauten Starliner niet geblokkeerd zitten in ISS

© Aangeboden door Belga

De twee astronauten die met de Boeing-ruimtecapsule Starliner drie weken geleden aankwamen in het internationale ruimtestation ISS, zitten daar "niet geblokkeerd". Dat heeft het Amerikaanse ruimteagentschap NASA vrijdag benadrukt. De terugkeer van de Starliner naar de aarde is ondertussen herhaaldelijk uitgesteld en zal er nu pas komen na nieuwe tests.

NASA benadrukt dat astronauten Starliner niet geblokkeerd zitten in ISS

© Aangeboden door Belga

De terugvlucht was aanvankelijk ten laatste op 26 juni gepland. NASA gaf geen nieuwe datum, maar liet eerder al weten dat de terugkeer van de Starliner met de twee astronauten Butch Wilmore en Suni Williams niet meer voor juni zou zijn.

Onderweg naar het ISS had de Starliner te maken gekregen met talrijke technische problemen. Er waren bijvoorbeeld heliumlekken opgetreden. Na problemen met de motoren slaagde het ruimteschip er pas bij de tweede poging in om aan te meren bij het ISS.

"Butch en Suni zijn niet geblokkeerd in de ruimte", benadrukte Steve Stich, een hoge verantwoordelijke van NASA, vrijdag tijdens een ongewoon gespannen persconferentie. De twee astronauten zouden aanvankelijk slechts iets meer dan een week in de ruimte blijven. In Amerikaanse media werd dan ook de vraag gesteld of de astronauten nog wel konden terugkeren naar aarde.

"We kunnen Starliner op elk moment terughalen", benadrukte Mark Nappi, een hoge verantwoordelijke bij Boeing. De eerste bemande vlucht van de Starliner was de ultieme testvlucht van de Boeing-ruimtecapsule, alvorens er reguliere vluchten mee uitgevoerd kunnen worden van en naar het ISS.

De Starliner, ontwikkeld en gebouwd door de Amerikaanse vliegtuigbouwer Boeing, maakte zijn eerste succesvolle onbemande vlucht in 2022.

NASA benadrukt dat astronauten Starliner niet geblokkeerd zitten in ISS

© Aangeboden door Belga

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29-06-2024 om 01:41 geschreven door peter  

De terugvlucht was aanvankelijk ten laatste op 26 juni gepland. NASA gaf geen nieuwe datum, maar liet eerder al weten dat de terugkeer van de Starliner met de 2 astronauten Butch Wilmore en Suni Williams niet meer voor juni zou zijn. 

Onderweg naar het ISS had de Starliner te maken gekregen met talrijke technische problemen. Er waren bijvoorbeeld heliumlekken opgetreden. Na problemen met de motoren slaagde het ruimteschip er pas bij de tweede poging in om aan te meren bij het ISS.

De capsule kon pas bij een tweede poging aanmeren bij het ISS

© Foto: AP

"Butch en Suni zijn niet geblokkeerd in de ruimte", benadrukte Steve Stich, een hoge verantwoordelijke van NASA, vrijdag tijdens een ongewoon gespannen persconferentie. De 2 astronauten zouden aanvankelijk slechts iets meer dan een week in de ruimte blijven. In Amerikaanse media werd dan ook de vraag gesteld of de astronauten nog wel konden terugkeren naar aarde.

"We kunnen Starliner op elk moment terughalen", benadrukte Mark Nappi, een hoge verantwoordelijke bij Boeing. De eerste bemande vlucht van de Starliner was de ultieme testvlucht van de Boeing-ruimtecapsule, alvorens er reguliere vluchten mee uitgevoerd kunnen worden van en naar het ISS.

De Starliner, ontwikkeld en gebouwd door de Amerikaanse vliegtuigbouwer Boeing, maakte zijn eerste succesvolle onbemande vlucht in 2022.

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29-06-2024 om 01:30 geschreven door peter  

Typically ranging from 5 to 500 micrometers in size and anywhere from a couple of million years to over 500 million years old, these tiny fossils are found mostly in sedimentary rocks, making them invaluable both to geologists and paleontologists. They help determine the age of rock layers, reconstruct past environments, and understand the evolutionary history of life on Earth. For instance, the presence of certain microfossils can indicate whether a rock layer was formed in a marine or terrestrial environment, providing insights into past climate conditions and geological events. Simply put, they offer a glimpse into what a specific area was like all those years ago.

Fossil specimen (left) and diagram (right) of Gangtoucunia aspera preserving soft tissues, including the gut and tentacle. Image credit: Luke Parry and Guangxu Zhang.

Credit: Luke Parry and Guangxu Zhang.

Fossil specimen of Gangtoucunia aspera preserving soft tissues, including the gut and tentacles (left and middle). The drawing at the right illustrates the visible anatomical features in the fossil specimens. Image credit: Luke Parry and Guangxu Zhang.

Credit: Luke Parry and Guangxu Zhang.

According to the researchers, Gangtoucunia would have looked similar to modern scyphozoan jellyfish polyps, with a hard tubular structure anchored to the underlying substrate. The tentacle mouth would have extended outside the tube, but could have been retracted inside the tube to avoid predators. Unlike living jellyfish polyps however, the tube of Gangtoucunia was made of calcium phosphate, a hard mineral that makes up our own teeth and bones. Use of this material to build skeletons has become more rare among animals over time.

Corresponding author Dr. Luke Parry, Department of Earth Sciences, University of Oxford, said, "This really is a one-in-million discovery. These mysterious tubes are often found in groups of hundreds of individuals, but until now they have been regarded as 'problematic' fossils, because we had no way of classifying them. Thanks to these extraordinary new specimens, a key piece of the evolutionary puzzle has been put firmly in place."

The new specimens clearly demonstrate that Gangtoucunia was not related to annelid worms (earthworms, polychaetes and their relatives) as had been previously suggested for similar fossils. It is now clear that Gangtoucunia's body had a smooth exterior and a gut partitioned longitudinally, whereas annelids have segmented bodies with transverse partitioning of the body.

The fossil was found at a site in the Gaoloufang section in Kunming, eastern Yunnan Province, China. Here, anaerobic (oxygen-poor) conditions limit the presence of bacteria that normally degrade soft tissues in fossils.

Ph.D. student Guangxu Zhang, who collected and discovered the specimens, said, "The first time I discovered the pink soft tissue on top of a Gangtoucunia tube, I was surprised and confused about what they were. In the following month, I found three more specimens with soft tissue preservation, which was very exciting and made me rethink the affinity of Gangtoucunia. The soft tissue of Gangtoucunia, particularly the tentacles, reveals that it is certainly not a priapulid-like worm as previous studies suggested, but more like a coral, and then I realized that it is a cnidarian."

Although the fossil clearly shows that Gangtoucunia was a primitive jellyfish, this doesn't rule out the possibility that other early tube-fossil species looked very different. From Cambrian rocks in Yunnan province, the research team have previously found well-preserved tube fossils that could be identified as priapulids (marine worms), lobopodians (worms with paired legs, closely related to arthropods today) and annelids.

Co-corresponding author Xiaoya Ma (Yunnan University and University of Exeter) said, "A tubicolous mode of life seems to have become increasingly common in the Cambrian, which might be an adaptive response to increasing predation pressure in the early Cambrian. This study demonstrates that exceptional soft-tissue preservation is crucial for us to understand these ancient animals."

The paper "Exceptional soft tissue preservation reveals a cnidarian affinity for a Cambrian phosphatic tubicolous enigma' will be published in Proceedings of the Royal Society B on Nov. 2.

Traditionally, the classification of microfossils has been a manual, time-consuming process requiring expert knowledge, with scientists staring into a microscope or at a computer screen for hours at a time. Given the sheer volume of data—potentially billions of microfossils from numerous slides—manual classification is tedious work, and attempting to classify all these microfossils is an insurmountable and impossible task. There are just too many of them, hence the advantage of letting AI assist in that process.

Spearheaded by a team from the University of Tromsø, The Arctic University of Norway, researchers have developed a novel method to automate the classification of microfossils. 

The study introduces a two-stage AI-driven pipeline to automate the detection and classification of microfossils from microscope images. 

The first stage involves using a pre-trained object detection model, YOLOv5, to identify and extract individual microfossils from high-resolution slide images. This model efficiently generates bounding boxes around each microfossil, a task that would be labor-intensive if done manually.

In the second stage, the researchers employ self-supervised learning (SSL) techniques to train models that can extract features from the detected microfossils. SSL is particularly advantageous in scenarios with limited labeled data, as it allows the model to learn useful representations from unlabeled data. The study compares two SSL frameworks, SimCLR and DINO, and finds that both significantly improve classification performance.

An image of the same slide of microfossils. On the left, the Machine learning approach. On the right, the pipeline of standard image processing methods. As the study notes, more fossils are separated with the machine learning approach as it is better able to differentiate the various fossil types.

(Image: Artificial Intelligence in Geosciences)

Basically, the AI is able to differentiate between different fossils and classify them. According to the study, this method is fast and computationally light, making it feasible to process and classify millions of microfossils efficiently. This scalability is crucial for handling the vast datasets typical in geological research. Moreover, as the AI classifies more fossils, it labels them and learns from its data, continuously adding to its own knowledge base. 

“This work shows that there is great potential in utilizing AI in this field,” explained Iver Martinsen, one of the study’s authors, in a press statement. “By using AI to automatically detect and recognize fossils, geologists might have a tool that can help them better utilize the enormous amount of information that wellbore samples provide.”

The ability to automate microfossil classification has profound implications for earth sciences. It can accelerate research in subsurface exploration, aiding in oil and gas exploration and carbon capture and storage projects. Moreover, the insights gained from microfossil analysis can contribute to broader scientific inquiries, such as studying past climate changes and mass extinction events. Understanding these historical patterns is essential for predicting future environmental changes and developing strategies to mitigate their impacts.

Close up photograph of the mouth region of Gangtoucunia aspera showing the tentacles that would have been used to capture prey. Image credit: Luke Parry and Guangxu Zhang.

Credit: Luke Parry and Guangxu Zhang.

“We are very happy with our results,” Martinsen concluded. “Our model exceeds previous benchmarks available out there. We hope that the present work will be beneficial for geologists both in industry and academia.”

• MJ Banias covers space, security, and technology with The Debrief. You can email him at mj@thedebrief.org or follow him on Twitter @mjbanias.

{ https://thedebrief.org/category/science/

https://phys.org/ }

29-06-2024 om 00:50 geschreven door peter  

The new research, undertaken by scientists with the British Antarctic Survey (BAS), reveals the problems posed by warm seawater. This water seeps into the lower portions of ground-based ice, thereby accelerating not only ice melt but also its movement into the surrounding ocean.

Additionally, the results could help climate researchers develop a clearer picture of how Antarctic ice melt contributes to rising sea levels and other changes that could impact far-reaching areas around the world in the years ahead.

BAS researcher Alex Bradley, who specializes in ice dynamics and served as lead author of the new study, says his team has identified what they believe could be “a new tipping point in Antarctic ice sheet melting.”

 “This means our projections of sea level rise might be significant underestimates,” Bradley recently warned in a statement.

CHILLING DISCOVERIES WITHIN THE GROUNDING ZONE

Bradley and his team’s study focuses on the grounding zone, which describes an area beneath the Antarctic ice sheet where the ground-based ice on the continent meets the sea.

Land-based ice in Antarctica moves gradually over long periods, making its way into the ocean, where it begins to melt once it meets the seawater. However, over time, climate change has been accelerating both the movement of the ice sheets and warming the surrounding seawater. Such processes are identified as major contributors to sea level rise, which can affect coastlines all around the world.

This process of speeding along the movement of Antarctica’s ice is further quickened by the presence of warmer seawater.

“Ice sheets are very sensitive to melting in their grounding zones,” Bradley recently said, adding that grounding zone melt he and his colleagues have observed “displays a ‘tipping point like’ behaviour, where a very small change in ocean temperature can cause a very big increase in grounding zone melting, which would lead to a very big change in flow of the ice above it.”

When warm water begins to seep into the grounding zone, cavities open up, allowing additional water into the area, precipitating the melt. Even a small increase in water temperature would likely significantly impact the amount of melting that occurs.

“Our results point towards a stronger sensitivity of ice-sheet melting,” Bradley and his co-author write in their recent study, emphasizing that such dynamics contribute to “higher sea-level-rise contribution in a warming climate” than scientists had previously been able to discern from past studies.

Satellite image of the ice surface from Radarsat with the valleys and ridges of the buried ancient mountains mapped.

(Supplied: Stewart Jamieson, Durham University)

ABSENT FROM EXISTING MODELS

Given that such factors are currently absent from models scientists rely on to determine the amount of melt that can occur, it seems likely that warm seawater and its impact on ice within the grounding zone can account for some of the accelerated shrinkage of ice sheets observed by the Intergovernmental Panel on Climate Change (IPCC) and others. This would also relate to ice sheets in other parts of the world apart from Antarctica such as Greenland, where similar ice melt has been observed to occur at rates faster than scientists expected based on existing models.

Bradly called the new data “missing physics” that, while remaining absent from current models, prohibits scientists from accurately projecting the potential impact of ice melt in the Earth’s polar regions.

“They don’t have the ability to simulate melting beneath grounded ice, which we think is happening,” Bradley says, adding that he and his colleagues are “working on putting that into our models now.”

This illustration shows what Antarctica would look like if the ice sheet were lifted from the continent. Highland A is a series of three hills in the East Antarctic.

(Supplied: Stewart Jamieson, Durham University)

Bradley and his team’s findings were detailed in a new study, “Tipping point in ice-sheet grounding-zone melting due to ocean water intrusion,” co-authored with Ian J. Hewitt and published in the journal Nature Geoscience on June 25, 2024.

• Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.

{ https://thedebrief.org/category/science/ }

29-06-2024 om 00:35 geschreven door peter  

Scientists were eager to analyze the 4.3-ounce (121.6-gram) sample, and now, less than a year after its arrival on Earth, a new study published in Meteoritics & Planetary Science has revealed the discovery of vital prebiotic compounds and minerals on Bennu’s rocky surface.

Jason Dworkin, OSIRIS-REx project scientist at NASA’s Goddard Space Flight Center and a co-author of the new paper, said the OSIRIS-REx mission “gave us exactly what we hoped: a large pristine asteroid sample rich in nitrogen and carbon from a formerly wet world.”

The asteroid’s composition, represented in the samples retrieved by OSIRIS-REx, offers scientists a look into the formation of the solar system and the components that may have played a role in the formation of life on Earth.

The analysis is key to confirming carbon and nitrogen-rich dusts and organic compounds essential for life. However, the sample also revealed a few surprises, including the presence of magnesium-sodium phosphate, which had not been detected in data obtained from the asteroid through remote sensing.

This significant finding points to the likelihood that Bennu may have its origins in a small, primitive ocean world since magnesium-sodium phosphate is a water-soluble phosphate that plays a crucial role in Earth’s biochemistry. The detections made in the Bennu samples were also very pure and of a size that set them apart from similar phosphates found in asteroid samples retrieved by JAXA’s Hayabusa2 mission.

Although it seems likely, based on the new data, that Bennu has a history involving interactions with water, the asteroid is still relatively chemically primitive, and somewhat paradoxically, researchers compare the elements it possesses to those of the Sun.

Confirming the presence of carbon and nitrogen in the asteroid samples obtained from Bennu’s surface allows researchers to glean new insights into environments where those elements formed, as well as how they became complex molecules over time. These processes would have once occurred early in Earth’s history, also a process that would have been fundamental in the formation of life.

Retrieving the samples directly from the surface of an asteroid also offered NASA scientists access to a veritable “time capsule” where the materials remained preserved for billions of years. Given their low density, such materials are destroyed when asteroids collide with Earth’s atmosphere, burning up during reentry.

Studying the preserved samples retrieved by OSIRIS-REx has already provided new insights toward understanding the intricate processes of solar system formation and prebiotic chemistry, but researchers involved in the ongoing analysis believe there will likely be more surprises in the near future.

“Each week, analysis by the OSIRIS-REx Sample Analysis Team provides new and sometimes surprising findings,” said Harold Connolly, co-lead author of the new study and OSIRIS-REx mission sample scientist at Rowan University.

Connolly said the ongoing discoveries Bennu’s samples are revealing “are helping place important constraints on the origin and evolution of Earth-like planets.”

The new paper by lead-author Dante Lauretta and colleagues, “Asteroid (101955) Bennu in the laboratory: Properties of the sample collected by OSIRIS-REx,” was published on June 26. Additional information about NASA’s OSIRIS-REx mission can be found on its official web page.

• Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.

{ https://thedebrief.org/category/space/ }

28-06-2024 om 22:37 geschreven door peter  

Trump Claims He Has Access To UFO Files. Here's What Experts Say

Donald Trump suggested in a recent interview with celebrity influencer Logan Paul that he has access to UFO files after being asked about what information he had about the existence of alien life.

The former president, appearing on Paul's ImPaulsive podcast, was asked what files or documents he was privy to on unidentified anomalous phenomena (UAP)—the term used by defense officials referring, in part, to sightings of what are colloquially called UFOs.

Trump's conversation comes amid heightened interest in the topic, following the Pentagon's release of declassified documents detailing instances reported to it by airmen and other service personnel.

Donald Trump recently claimed he had received briefings about alien life and UFOs while in office. The president was pressed during an interview with celebrity influencer Logan Paul. 

REUTERS/GETTY IMAGES

Last summer, 36-year-old Air Force veteran David Grusch caused a media storm after he said that a top-secret U.S. military program had found the wreckage of several fully intact unidentified aerial craft, claiming some of which contained dead nonhuman pilots.

A 2023 report from the Office for the Director of National Intelligence found that there were 510 UAP sightings in 2022, higher than the 366 seen in 2021. Of these, 171 were considered to "appear to have demonstrated unusual flight characteristics or performance capabilities, and require further analysis."

During the podcast, when asked about aliens, Trump said he had spoken to Air Force personnel who had claimed to see aircraft "round in form, going like four times faster than my super jet fighter plane."

"I have met with people that are serious people that say there are some really strange things they see flying around out there," he added.

Pressed whether he had access to information on alien life and UAPs, Trump replied, "I have access...and I speak to people about it, I've had actually meetings on it, and they will tell you there's something going on.

"When they say things, things are going four times faster than my beautiful top-of-the-line airplane that goes, you know, real fast, Mach 2, right?"

Newsweek has contacted media representatives for Donald Trump via email for comment.

Newsweek has also spoken to experts on what access Trump may have and if that privileges him to any information about UFOs while he is no longer in office.

What can Trump access?

The answer to this has been addressed, in part, through the discussion that followed Trump's handling of confidential documents, claiming that he had the authority as a former president to hold on to papers—a claim that Newsweek has previously explored.

President Joe Biden has restricted Trump from some information, specifically intelligence briefings, arguing the former president could reveal sensitive information. Speaking to CBS Evening News in February 2021, Biden said the decision had been motivated by Trump's "erratic behavior, unrelated to the insurrection."

Asked what his worst fear was if Trump continued to receive the briefings, Biden said: "I'd rather not speculate out loud."

"I just think that there is no need for him to have the intelligence briefing," he added.

"What value is giving him an intelligence briefing? What impact does he have at all, other than the fact he might slip and say something?"

While this restricts some documentation, these briefings are usually only offered as a courtesy and, in any case, are unlikely to contain information about UAPs unless they present an immediate or near-future security risk.

However, under the Presidential Records Act, Trump can only access material that originated in his four years as president per the archivist's approval, according to Gail Helt, a former CIA official and a professor of political science at King University.

"These would be documents that originated inside his White House, not the intelligence community or DOD," Helt told Newsweek.

"He would have no continued access, nor the right to such continued access, to any classified documents that originated with the CIA, FBI, DOD, etcetera, at all. Those are not his property; those belong to the intelligence community (IC) or, rather, to the nation, which trusts the IC to keep them secret."

Helt added that "if he wanted a briefing on a particular national security issue, or to access the classified intelligence record on UAPs from his four years in office, he would need to request that access from the White House."

There has been no suggestion that the documents found at Mar-a-Lago contained any information on UAPs.

Though Helt said, "I don't think that the fact that classified documents related to UAPs were not mentioned as having been present in the Mar-a-Lago stash suggests that they were not there.

"We don't know exactly what was in that trove of documents, and given the sensitivity of the topic of UAPs generally, I doubt anyone would call out the existence of such documents even in vague terms.

So what's left?

Based on the descriptions given to experts about Trump's privileges, and the fact that the only papers he could access would be those created in the White House while he was in office—and not from security agencies that are coordinating investigations into UAP sightings—it is not entirely clear what information he could have, if any.

In 2023, Trump told podcast host Hugh Hewitt that he had been briefed about UAPs while in office, saying that he interviewed "a couple of people from the Air Force" without elaborating. This could be the information he may be referring to, but what more those briefings would have revealed beyond the reports that have already been declassified and investigated by the Pentagon isn't clear.

In December 2020, Trump signed a $2.3 trillion government funding bill that also compelled intelligence services to provide Congressional committees with an unclassified report about UAPs, helping the topic's popularity to skyrocket. However, that effort was engineered by Congress, not the president, and Trump was out of office for more than a year by the time it was released.

While it's feasible that Trump may have held notes or information that passed through the White House at some point, when pressed for detail Trump has remained vague.

Considering what little he has said, his limited access to White House documents, no access to Pentagon documents, and the fact that the great deal of Congressional and Washington attention to UAPs has occurred during the Biden presidency, it seems unlikely that Trump is holding on to any wild truths or information not already revealed through committee hearings and Pentagon reports. That does not mean he has nothing, but in all likelihood, whatever he possesses may be pretty slim and inconsequential.

{ https://www.newsweek.com/ }

28-06-2024 om 22:24 geschreven door peter  

Originally discovered among the wreckage of a shipwreck along the Greek island of Antikythera in 1901, the mysterious mechanism has long intrigued modern scientists and engineers, primarily because it appears to be a singular invention, with no other similar devices from this period known to exist.

Now, researchers with the University of Glasgow have employed statistical modeling techniques originally developed for analyzing ripples in spacetime to determine how many holes likely existed in one of the famous Antikythera mechanism’s broken rings.

At the time of its discovery, the Antikythera mechanism was in a highly eroded state, having spent close to two thousand years amidst the wreckage of a ship that sank near the Aegean Island of Antikythera, the device’s namesake.

Roughly the size of a shoebox, the device features an array of intricately tooled gears that are surprisingly complex for any innovation from the second century BCE. Over the decades, studies of the device have revealed that it likely functioned as a hand-operated computer that would have allowed its operator to predict the arrival of eclipses, as well as calculate the positions of planets over time.

Fast forward to 2020, when X-ray images of one of the device’s components, which researchers identify as its calendar ring, unveiled new features that included a series of regularly spaced holes beneath the ring. Given its highly eroded state, the presence of rings could be discerned, although the number remained unclear, with estimates suggesting anywhere between 347 and 467 of the holes having once existed along this damaged portion of the device.

Now, in new research published in the Horological Journal, Glasgow researchers outline their use of a pair of statistical techniques in a new effort to refine the previously estimated number of holes that once existed in this region of the Antikythera mechanism. Applying Bayesian analysis and, notably, new techniques from gravitational wave research, the team determined that the ring likely contained 354 holes.

This is significant since the 354 holes on the device would have perfectly aligned with the Greek lunar calendar, as opposed to the Egyptian calendar’s 365 holes. Based on the new analysis, the presence of 354 holes is hundreds of times more probable than the previously considered 360-hole count.

Professor Graham Woan, a co-author of the paper, explained that he became interested in the problem after being introduced to data by YouTuber Chris Budiselic, who was creating a replica of the calendar ring.

“Towards the end of last year, a colleague pointed to me to data acquired by YouTuber Chris Budiselic, who was looking to make a replica of the calendar ring and was investigating ways to determine just how many holes it contained.”

Woan said Budiselic’s conundrum “struck me as an interesting problem, and one that I thought I might be able to solve in a different way during the Christmas holidays.” Woan then went to work employing statistical techniques to see if a definitive answer could be obtained.

Dr. Joseph Bayley, a colleague of Woan’s at the University’s Institute for Gravitational Research, further refined the research by adapting techniques used in analyzing LIGO gravitational wave data to study the calendar ring. Their combined approaches, including Markov Chain Monte Carlo and nested sampling, confirmed the probability of 354 or 355 holes with a precision of about 1/3 mm.

Additionally, the new analysis also reveals the extraordinary accuracy of the holes’ placement, with an average radial variation of just 0.028mm. According to Bayley, the use of these dual approaches to resolving the lingering questions about the Antikythera mechanism showcases the truly remarkable skill employed by the device’s mysterious builder(s).

“It’s given me a new appreciation for the Antikythera mechanism and the work and care that Greek craftspeople put into making it,” Bayley said. “[T]he precision of the holes’ positioning would have required highly accurate measurement techniques and an incredibly steady hand to punch them.”

Professor Woan says using contemporary techniques to study an ancient device designed to track celestial events will enhance the research community’s appreciation of ancient technological achievements like the Antikythera mechanism, which represents a singularly unique and innovative construction.

“We hope that our findings about the Antikythera mechanism, although less supernaturally spectacular than those made by Indiana Jones, will help deepen our understanding of how this remarkable device was made and used by the Greeks,” Woan said in a statement.

{ https://thedebrief.org/category/tech/ }

28-06-2024 om 22:03 geschreven door peter  

By KAMAL SULTAN

A couple were left stunned after they spotted UFOs 'as bright as the sun' hovering above a river in Canada.

Justin Stevenson and his wife Danielle Daniels-Stevenson were driving through Fort Alexander on May 14 when they saw the bright lights above the Winnipeg River.

Kennedy News and Media

He pulled over at a clearing where Danielle, 32, filmed two 'sun-like' balls of light floating above the tree line without making a sound.

Justin, 49, can be heard declaring 'I think we're seeing some aliens' as another two appear 'from nowhere' and begin moving downwards.

Other clips show two UFOs continuing to hover while the bemused pair sit in their vehicle for half an hour to watch them.

Observers called the footage a “strange anomaly” and “a clear shot of UFOs.

”Kennedy News & Media

Justin, previously a sceptic of extraterrestrial life, said the experience felt 'like he was in a sci-fi movie' and it's given him 'proof there's something out there other than humans'.

Danielle posted one of the clips on Facebook later that night where it's been viewed more than 650,000 times with users calling it a 'strange anomaly' and 'a clear shot of UFOs'.

Others have claimed they're helicopters, drones or flares dropped from planes but mechanic Justin disagrees and is adamant there's no explanation for the sighting.

Justin, from Manitoba, Canada, said: 'My wife saw lights and we were confused at what they were so we drove to a clearing where we could see properly.

'There were two really bright lights above the river almost like the sun shining but the sun had set by this time. They were super bright like a fire in the sky.

'They were sitting above the tree line for the longest time then they started to move down and then two more popped up right out of nowhere.

'There were six all together and they didn't even make a sound.

'I just thought 'what the f**k?'. That's when I realized it wasn't a fire and I questioned if it was aliens.

He pulled over at a clearing where Danielle, 32, filmed two 'sun-like' balls of light floating above the treeline without making a sound

Justin, 49, can be heard declaring 'I think we're seeing some aliens ' as another two appear 'from nowhere' and begin moving downwards

'It was pretty surreal and it felt like we were in a sci-fi movie.

'I was skeptical before I saw this but now this has given me the proof I need that there's something out there other than humans.

'There's no explanation so we posted it because we wanted people to describe for themselves what that is.

'The naysayers can have their opinion but I disagree.'

Danielle's post read: 'We saw this just a few mins ago. What is it? It lasted like half an hour.'

One social media user commented: 'Oh wow!! You're brave to record this. I would've taken off.'

A second wrote: 'Oh my word! What is that? Pretty scary that it's so close to home, yikes!'

A third added: 'That is one strange anomaly.'

A fourth said: 'UFO that's a nice clear shot ... Wow.'

However some disagreed and wrote: 'Looks like helicopters.'

Another commented: 'It could be flares that planes drop.'

{ https://www.dailymail.co.uk/ }

28-06-2024 om 21:47 geschreven door peter  

Australia discussed 'UFO collection planning' with US in secret meeting

{ https://www.northweststar.com.au/ }

28-06-2024 om 21:17 geschreven door peter  

NASA Release 3D Visualization of ‘Pillars of Creation’

Using images from the NASA/ESA Hubble Space Telescope and the NASA/ESA/CSA James Webb Space Telescope, astronomers have produced a new 3D visualization of the Pillars of Creation, three towers of gas and dust within the Eagle Nebula.

The Pillars of Creation are three towers of gas and dust located some 6,500 light-years away in the constellation of Serpens.

They are a fascinating but relatively small feature of the Eagle Nebula (also known as Messier 16), which was discovered in 1745 by the Swiss astronomer Jean-Philippe Loys de Chéseaux.

The Pillars of Creation are approximately 4-5 light-years long, while the nebula is 55-70 light-years wide.

They arise when immense, freshly formed blue-white O- and B-type stars give off intense ultraviolet radiation and stellar winds that blow away less dense materials from their vicinity.

“By flying past and amongst the pillars, viewers experience their 3D structure and see how they look different in the Hubble visible-light view versus the Webb infrared-light view,” said Dr. Frank Summers, principal visualization scientist at the Space Telescope Science Institute.

“The contrast helps them understand why we have more than one space telescope to observe different aspects of the same object.”

“The four Pillars of Creation, made primarily of cool molecular hydrogen and dust, are being eroded by the fierce winds and punishing ultraviolet light of nearby hot, young stars.”

“Finger-like structures larger than the Solar System protrude from the tops of the pillars. Within these fingers can be embedded, embryonic stars.”

“The tallest pillar stretches across 3 light-years, three-quarters of the distance between our Sun and the next nearest star.”

A mosaic of visible-light (Hubble) and infrared-light (Webb) views of the same frame from the Pillars of Creation visualization.

Image credit: Greg Bacon / Ralf Crawford / Joseph DePasquale / Leah Hustak / Christian Nieves / Joseph Olmsted / Alyssa Pagan / Frank Summers, STScI / NASA’s Universe of Learning.

The movie takes visitors into the 3D structures of the Pillars of Creation.

“The Pillars of Creation were always on our minds to create in 3D,” said Dr. Greg Bacon, also from the Space Telescope Science Institute.

“Webb data in combination with Hubble data allowed us to see the Pillars in more complete detail.”

“Understanding the science and how to best represent it allowed our small, talented team to meet the challenge of visualizing this iconic structure.”

The new visualization helps viewers experience how two of the world’s most powerful space telescopes work together to provide a more complex and holistic portrait of the pillars.

Hubble sees objects that glow in visible light, at thousands of degrees. Webb’s infrared vision, which is sensitive to cooler objects with temperatures of just hundreds of degrees, pierces through obscuring dust to see stars embedded in the pillars.

“When we combine observations from NASA’s space telescopes across different wavelengths of light, we broaden our understanding of the Universe,” said Dr. Mark Clampin, astrophysics division director at NASA Headquarters.

“The Pillars of Creation region continues to offer us new insights that hone our understanding of how stars form.”

“Now, with this new visualization, everyone can experience this rich, captivating landscape in a new way.”

{ https://www.sci.news/ }

28-06-2024 om 21:04 geschreven door peter  

Stel dat er op vele lichtjaren afstand een intelligente beschaving op ontdekking wacht, dan gaan we die misschien wel vinden dankzij broeikasgassen die deze intelligente aliens met opzet in hun atmosfeer pompen.

Met dat wilde idee komen Amerikaanse onderzoekers op de proppen in het blad The Astrophysical Journal.

Atmosfeer
Afgaand op het grote aantal planeten in het universum en het feit dat bouwblokken voor leven in datzelfde universum alomtegenwoordig zijn, zou je verwachten dat ook elders in de ruimte leven te vinden is. Toch hebben we het tot op heden niet kunnen vinden. Maar de zoektocht is nog altijd in volle gang. Een belangrijke rol is daarbij onder meer weggelegd voor de ruimtetelescoop James Webb, waarmee onderzoekers in de atmosfeer van buitenaardse werelden kunnen jagen op zogenoemde biosignaturen: gassen die hinten op de aanwezigheid van leven, zoals bijvoorbeeld (hoge concentraties) zuurstof, methaan en/of ozon.

Maar er zijn nog meer gassen die de aanwezigheid van (intelligente) aliens kunnen verraden, zo schrijven Amerikaanse onderzoekers nu. In hun nieuwe studie tonen ze namelijk aan dat het mogelijk moet zijn om broeikasgassen die aliens met opzet in hun atmosfeer pompen, met behulp van James Webb te detecteren.

Intelligente actie
Met opzet broeikasgassen in je atmosfeer brengen: dat klinkt misschien – met wat wij weten over de gevolgen van de broeikasgassen die we zelf in onze atmosfeer hebben gebracht – niet direct als een heel intelligente actie. Toch kan het zomaar zijn dat intelligente aliens er – op vele lichtjaren afstand van de aarde – bewust voor kiezen om hun atmosfeer met broeikasgassen te bewerken. Bijvoorbeeld om een naderende ijstijd af te wenden of een iets te koude planeet geschikt te maken voor kolonisatie.

Fluor
De aliens zouden daar verschillende gassen voor kunnen gebruiken, zo onthullen de onderzoekers. Ze denken dan bijvoorbeeld aan met fluor verrijkte versies van methaan, ethaan, propaan, stikstof en zwavel. Dergelijke gassen komen in de natuur niet in significante hoeveelheden voor. Dat betekent dat als James Webb ze in hoge concentraties in buitenaardse atmosferen aantreft, dat een sterke aanwijzing kan zijn voor de aanwezigheid van intelligente aliens die deze gassen eigenhandig hebben gemaakt, omdat ze ontevreden zijn met hun klimaat en het willen veranderen.

Artist's concept of an exoplanet in the process of being terraformed.

CREDIT - Thibaut Roger/University of Bern

Weinig en lang
Maar waarom zou een alien nu uitgerekend een met fluor verrijkte versie van methaan of zwavel inzetten om zijn klimaat aan te passen? Daar zijn meerdere goede redenen voor te bedenken, zo stellen de onderzoekers. Een groot voordeel van dergelijke gassen is dat het heel effectieve broeikasgassen zijn. Zo is een verbinding van zwavel met fluor – ook wel zwavelhexafluoride genoemd – een 23.000(!) keer potenter broeikasgas dan CO2. Met relatief kleine hoeveelheden kun je dan ook al een flinke klimaatverandering realiseren. Een ander voordeel van dergelijke gassen is dat ze heel lang in de atmosfeer blijven hangen; tot wel 50.000 jaar. Dat betekent dat de aliens niet voortdurend nieuwe gassen in de atmosfeer hoeven te pompen om het door hen veranderde klimaat ook langdurig te kunnen handhaven.

Zichtbaar
Kortom: er zijn verschillende goede redenen waarom aliens die ontevreden zijn met hun klimaat naar deze gassen zouden kunnen grijpen. En als ze dat op een relatief nabije exoplaneet doen, kunnen we daar met bestaande instrumenten – zoals de James Webb-telescoop – getuige van zijn, zo meent onderzoeker Edward Schwieterman. “Als in een atmosfeer zoals de onze slechts 1 op elke 1 miljoen moleculen zo’n broeikasgas is, zouden we het mogelijk nog kunnen detecteren. En een dergelijke concentratie zou ook genoeg zijn om het klimaat te veranderen,” voegt hij eraan toe.

Hoewel we natuurlijk niet met zekerheid kunnen concluderen dat aliens met behulp van deze gassen hun klimaat aanpassen, staat voor de onderzoekers wel vast dat als ze het doen, wij dat waarschijnlijk kunnen zien. Een goede reden om naast de zoektocht naar biosignaturen ook onze ogen open te houden voor deze ‘technosignaturen’; signalen voor de aanwezigheid van technologisch geavanceerd en intelligent buitenaards leven. “Je hoeft geen extra inspanning te doen om naar deze technosignaturen te zoeken op het moment dat je met een telescoop al bezig bent om een planeet om andere redenen nader te karakteriseren,” merkt Schwieterman op. “En het zou adembenemend zijn als we ze vinden.”

lees ook

• NASA: thuiswereld van Spock gaat ook in het echt in rook op

• Alsof het nooit anders is geweest: wetenschappers geven mensen een extra duim - en die wennen daar vervolgens bizar snel aan

• Sterke aanwijzingen gevonden dat er ergens tussen 1990 en 1992 op Venus een vulkaan is uitgebarsten

Bronmateriaal

• "Telltale greenhouse gases could signal alien activity" - University of California - Riverside
  Afbeelding bovenaan dit artikel: ThankYouFantasyPictures from pixabay (via Canva Pro)

{ https://scientias.nl/ }

28-06-2024 om 20:57 geschreven door peter  

James Webb zoomt in op een ‘saai’ stukje Jupiter – maar dat blijkt helemaal niet zo saai te zijn

Vivian Lammerse

De telescoop tuurde naar het gebied boven de beroemde Grote Rode Vlek van Jupiter en ontdekte een reeks nieuwe, nog nooit eerder waargenomen kenmerken.

Jupiter is zonder twijfel een van de meest opvallende objecten aan de nachtelijke hemel. Bovendien is de enorme gasreus op een heldere nacht eenvoudig te aanschouwen. Afgezien van de heldere noorder- en zuiderlichten in de poolgebieden van de planeet, is de gloed van Jupiters bovenste atmosfeer zwak, waardoor het moeilijk is om met aardse telescopen details te zien. Maar gelukkig hebben we de James Webb-telescoop, die dankzij zijn infraroodgevoeligheid in staat is om de bovenste atmosfeer van Jupiter direct boven de Grote Rode Vlek met ongeëvenaarde precisie te bestuderen.

Meer over Jupiter’s Grote Rode Vlek
Planeet Jupiter staat bekend om zijn kleurrijke banden en reusachtige, wervelende stormen. De bekendste storm is – misschien zelfs de bekendste in het hele zonnestelsel – de Grote Rode Vlek; een gigantische anticycloon die al heel wat jaren op de gasreus woedt. De Grote Rode Vlek is een immense atmosferische wervelwind, zo is hij bijna net zo groot als de aarde in diameter. Aan zijn buitenranden razen de winden met snelheden tot 450 kilometer per uur. De rode kleur ontstaat door chemische reacties in de atmosfeer, wat een opvallend contrast vormt met de bleke wolken van de gasreus. De Grote Rode Vlek heeft generaties van wetenschappers gefascineerd. Dat heeft onder andere met zijn omvang te maken, maar ook met het feit dat de storm zelfs zichtbaar is met kleine telescopen. Afgelopen week werd nog bekend dat de Grote Rode Vlek toch jonger is dan gedacht. Hoewel de immense storm met een respectabele leeftijd van 190 jaar nog altijd de langstlevende wervelwind in het zonnestelsel is, blijkt hij niet dezelfde te zijn als die astronoom Giovanni Cassini in 1665 waarnam.

De bovenste atmosfeer van Jupiter is de overgangslaag tussen het magnetisch veld van de planeet en de onderliggende atmosfeer. In dit gebied zijn de heldere en levendige noorder- en zuiderlichten te zien, aangedreven door vulkanisch materiaal dat wordt uitgestoten door Jupiters ‘pizzamaan’ Io. Dichter bij de evenaar wordt de structuur van deze atmosfeer beïnvloed door het binnenkomende zonlicht. Omdat Jupiter slechts 4 procent van het zonlicht ontvangt dat de aarde bereikt, dachten astronomen dat dit gebied vrij uniform zou zijn.

Saai
In juli 2022 werd Jupiters Grote Rode Vlek geobserveerd met Webb’s Near-InfraRed Spectrograph (NIRSpec), waarbij de Integral Field Unit van het instrument werd gebruikt. Het doel was om te bestuderen of het gebied direct boven de beroemde wervelstorm echt zo saai is als wetenschappers vermoedden. Maar tot hun verrassing hebben ze nu ontdekt dat de bovenste atmosfeer een verscheidenheid aan ingewikkelde structuren bevat, waaronder donkere bogen en heldere vlekken, zo valt er te lezen in Nature Astronomy. “We gingen er misschien wat naïef vanuit dat dit gebied echt saai zou zijn,” zegt teamleider Henrik Melin. “Maar het blijkt eigenlijk net zo interessant te zijn als de noorderlichten, zo niet interessanter. Jupiter blijft ons altijd verrassen.”

Zwaartekrachtsgolven
Kortom, het gebied dat vroeger als onopvallend werd beschouwd, blijkt nu dus een diverse verzameling van complexe structuren en activiteiten te bevatten. Hoewel de lichtuitstraling van dit gebied wordt veroorzaakt door zonlicht, suggereert het team dat er een ander mechanisme moet zijn dat de vorm en structuur van de bovenste atmosfeer beïnvloedt. “Een manier om deze structuur te veranderen is door zwaartekrachtsgolven,” legt Henrik uit. “Dit is vergelijkbaar met golven die op een strand breken en rimpelingen in het zand veroorzaken. Deze golven ontstaan diep in de turbulente lagere atmosfeer rondom de Grote Rode Vlek. Ze kunnen omhoog bewegen naar hogere lagen, wat leidt tot veranderingen in de structuur en uitstoot van de bovenste atmosfeer.” Dergelijke atmosferische golven kunnen soms ook op aarde worden gezien, maar ze zijn veel zwakker dan die waargenomen op Jupiter door Webb.

Jupiter’s atmosphere around the Great Red Spot (NIRSpec image)

Vervolgonderzoek
Het team hoopt in de toekomst vervolgonderzoek te doen met Webb naar Jupiters complexe golfpatronen. Zo willen ze bijvoorbeeld achterhalen hoe deze patronen zich in de bovenste atmosfeer van de planeet bewegen. Ook willen ze meer inzicht krijgen in de energiebalans in dit gebied en bestuderen hoe de kenmerken ervan in de loop van de tijd veranderen.

Juice
Maar dat niet alleen. Deze ontdekkingen kunnen ook van belang zijn voor de ESA’s Jupiter Icy Moons Explorer (Juice), die op 14 april 2023 werd gelanceerd. Juice zal uitgebreide waarnemingen doen van Jupiter en zijn drie grote manen met oceanen – Ganymedes, Callisto en Europa (lees hier meer over de missie). De missie heeft tot doel deze manen te karakteriseren, terwijl het ook Jupiters complexe omgeving in detail zal onderzoeken.

Dankzij de nieuw opgedane kennis van de atmosferische processen en dynamiek op Jupiter, krijgen we een steeds beter beeld van deze nog altijd raadselachtige planeet en zijn manen. En hopelijk zal dit niet alleen ons begrip van ons eigen zonnestelsel vergroten, maar ook bijdragen aan onze kennis van gasreuzen en hun manen elders in het universum.

LEES OOK

• NASA: thuiswereld van Spock gaat ook in het echt in rook op

• Alsof het nooit anders is geweest: wetenschappers geven mensen een extra duim - en die wennen daar vervolgens bizar snel aan

• Sterke aanwijzingen gevonden dat er ergens tussen 1990 en 1992 op Venus een vulkaan is uitgebarsten

Bronmateriaal

• "Jupiter’s upper atmosphere surprises astronomers" - ESA
  
• Afbeelding bovenaan dit artikel: GustavoAckles van Pixabay (via Canva Pro)

{ https://scientias.nl/ }

28-06-2024 om 20:53 geschreven door peter  

Tot daar dan die kolonisatie? Bijna dagelijks vallen meteorieten op Mars, die stevige kraters maken

Redelijk relevant nieuws voor toekomstige missies naar Mars: de planeet krijgt haast dagelijks te maken met inslagen door meteorieten. Uit onderzoek van Zwitserse en Britse wetenschappers blijkt dat de planeet zelfs ruim vijf keer meer inslagen kent dan eerder geschat. De meteorieten laten kraters achter met een diameter van minstens acht meter.

ADN 

Bron: Belga

Een internationaal team wetenschappers van de ETH in Zürich en het Imperial College in Londen heeft een nieuwe kijk op de zaak gebracht door geluiden in kaart te brengen. “Het lijkt efficiënter om te luisteren naar het geluid van de inslagen om te bepalen met welke frequentie ze gebeuren”, klinkt het bij Gareth Collins, mede-auteur van het artikel dat in ‘Nature Astronomy’ is verschenen.

De zogenaamde SEIS-seismograaf, een instrument geproduceerd onder toezicht van het Franse CNES (National Centre for Space Studies), werd in november 2018 op Mars geïnstalleerd dankzij de InSight-lander van NASA. Die seismograaf wordt nu gebruikt om de inslagen te meten op basis van hun geluid.

Jaarlijks tussen 280 en 360 meteorietinslagen

Uit het onderzoek blijkt dat Mars jaarlijks tussen 280 en 360 meteorietinslagen te verwerken krijgt, die een krater van minstens acht meter diep nalaten. Dat is vijf keer meer dan wat eerst werd gedacht. Elke maand zou de planeet getroffen worden door een meteorietinslag die een krater van dieper van dertig meter nalaat. Bijna dagelijks wordt Mars getroffen door meteorieten ongeveer zo groot als een basketbal. Kleinere inslagen meten is moeilijk aangezien de planeet te maken heeft met zandstormen die de minder diepe kraters vaak bedekken en onzichtbaar maken.

“Omdat inslagen met hoge snelheid explosiezones creëren die nog eens vaak minstens 100 keer groter zijn dan de krater, is het voor de veiligheid van missies - nu met robots, maar in de toekomst ook met mensen - belangrijk om het exacte aantal inslagen te kennen”, aldus de onderzoekers.

“De studie is de eerste in haar soort die seismologische gegevens gebruikt om de frequentie van meteorietinslagen te berekenen. Met de resultaten moet rekening gehouden worden bij het inplannen van toekomstige missies naar Mars”, beklemtoont professor Domenico Giardini van ETH Zürich.

KIJK OOK. 

• https://youtu.be/O1AtaSCyqJI

• https://youtu.be/37VMwfVhpRY

Zo heeft Curiosity op acht november een opname gemaakt van zonsopgang tot zonsondergang.

Beelden van de voorkant van de rover.

Credit: NASA

Beelden van de achterkant van de rover.

Credit: NASA

{ https://www.hln.be/ }

28-06-2024 om 18:30 geschreven door peter  

“It’s a very interesting proposal that we hope gets picked up,” Rusty Schweickart said.

DeMartini’s concept for what he calls the Sunward NEO Surveillance and Early Twilight detection collaboration — or SUNSET for short — was judged the top entry in the competition for the Schweickart Prize. The award, which is a program of the California-based B612 Foundation, recognizes graduate students who come up with innovative ideas for planetary defense. As the prize winner, DeMartini will receive a $10,000 cash prize and a trophy topped by an authenticated meteorite during a ceremony on June 29 at the Chabot Space & Science Center in Oakland, Calif.

“The thing that actually got me to put my idea forward was the meteorite fragment,” said DeMartini, who’s earning his Ph.D. from the University of Maryland. “I saw that and I was like, ‘Oh my gosh, I really want that.’ But maybe that’s just me being an asteroid nerd.”

DeMartini said the idea behind SUNSET came out of discussions he had with a colleague about the asteroid that sparked the Chelyabinsk blast. “The reason we didn’t have any warning was because it came from the direction of the sun, and we can’t look in the direction of the sun,” he said. “That got me thinking, ‘Wow, that’s a region we should really monitor.'”

It turns out that the Rubin Observatory is looking into conducting just such a monitoring effort after it gets up and running next year. DeMartini suggests that the SUNSET network could augment the sightings made at the Rubin Observatory, and confirm the precise orbits traced by sunward NEOs.

“If these other telescopes know where to point in advance, then they can follow up on anything that Rubin discovers in a night, and then we can get these confirmations more easily,” he said.

The current focus of DeMartini’s research actually has to do with a different topic: numerical simulations of asteroid surfaces and interiors, and how close encounters with Earth might change those values. But when his faculty adviser told him about the Schweickart Prize, DeMartini decided to enter the competition.

It should come as no surprise that Rusty Schweickart himself was one of the judges. In his post-NASA career, he has focused on the challenges of asteroid threat detection and mitigation. He’s the founder and past president of the Association of Space Explorers, which took up the NEO threat as one of its causes. He’s also a co-founder of the B612 Foundation, which raises awareness about planetary defense, and a co-founder of Asteroid Day as well.

“What we’re talking about here in planetary defense is having the capability to ever so slightly, but critically, reshape the solar system to enhance the future of life on Earth,” Schweickart said. “To prevent this existential threat — that is what I’ve dedicated the last 20 years of my life to bringing about.”

Thanks in part to a congressional mandate, more than 90% of the biggest near-Earth asteroids, exceeding a kilometer (0.6 mile) in diameter, are thought to have been identified and are being tracked. That’s the kind of asteroid that wiped out the dinosaurs roughly 66 million years ago. “But it’s the ones that are the city-killers — the 40- to 50-meter-diameter guys — that you can’t see until they’re pretty close to the Earth,” Schweickart said. “That means looking interior [to Earth’s orbit] is going to be more productive than looking exterior.”

DeMartini’s proposal was selected as the winner because it addresses one of the biggest gaps in asteroid monitoring, and because it takes advantage of advances in observational firepower.

The Rubin Observatory’s Survey Cadence Optimization Committee, or SCOC, says doing the kind of twilight sky survey that DeMartini discusses in his SUNSET proposal would be “scientifically compelling.” It recommends starting such a survey soon after the telescope begins science operations next year.

“We currently are simulating the effect of adding low-solar-elongation observations during the start and end of twilight, spending about 15 to 20 minutes of the start and end of about a quarter of the survey nights observing at high airmass toward the sun,” Lynne Jones, an astronomer who’s part of the Rubin team, said in an email. “This gives us the opportunity to detect asteroids interior to the Earth, even down to parts of the sky which are closer than 40 degrees from the sun.”

This time-lapse simulation illustrates how the Rubin Observatory could focus on twilight zones at the start and end of a survey night.

Credit: Lynne Jones / Aerotek / Rubin Observatory.

DeMartini said the Rubin Observatory’s twilight survey campaign would be “step one” in his vision for the SUNSET collaboration. “The next bit, I suppose, would be networking. Hopefully, this event that I’ll be going to when I’m receiving the prize will be a good opportunity for that. And that’s something that B612 can really help with,” he said.

“If it takes off, I don’t know what it looks like in 10 years. But my hope is that we’re safer because of it,” DeMartini added.

Randy Schweickart, who is one of Rusty’s sons and the chair of the prize program’s judging committee, said he and other family members are committed to funding the Schweickart Prize for at least five years. “The hope is that — similar to the Astronaut Scholarship Foundation, which has expanded tremendously from its beginnings — there would be support from other sources as we move in time and are able to get more of the word out,” he said.

Rusty Schweickart said that the prize is meant for more than astronomers. “The really toughest problems related to planetary defense are the governance issues — the non-technical, geopolitical and legal issues,” he said. “So, in the future, what we want to do is move more in that direction, and get law students, economics students, public-safety people, emergency-response people to be involved in this. Because in the end, they’re going to be very critical.”

Schweickart, who’ll turn 90 next year, hopes the prize will carry on his legacy when he’s “pushing up daisies.”

“It seems to me that that we have, as human beings, a special responsibility to do whatever we can to see that this evolutionary experiment that we’re having here on planet Earth continues,” he said. “I’m not quite sure why that’s the responsibility, but I think it is. And if so, I feel obligated to do what I could.”

Scores of events have been scheduled around the world to mark Asteroid Day, including a two-day festival in Luxembourg. The award ceremony for the Schweickart Prize will take place at 3:30 p.m. PT June 29 at the Chabot Space & Science Center in Oakland, Calif. The event will feature a presentation by Rusty Schweickart, plus comments from NASA astronauts Steve Smith and Nicole Stott, and from YouTube space commentator Scott Manley. Click to purchase tickets.

Founding Sponsors who have funded the Schweickart Prize program include Anousheh Ansari, Barringer Crater Company, B612 Foundation, Future Ventures, Geoffrey Notkin, Jurvetson Family Foundation, Meteor Crater, Randy Schweickart and Michelle Heng, and Rusty B. Schweickart and Joanne Keys.

{ https://www.universetoday.com/ }

28-06-2024 om 17:40 geschreven door peter  

“Atmospheric pollutants such as chlorofluorocarbons and NO₂ have been proposed as potential remotely detectable atmospheric technosignature gases,” the authors write in their paper. “Here, we investigate the potential for artificial greenhouse gases, including CF₄, C₂F₆, C₃F₈, SF₆, and NF₃, to generate detectable atmospheric signatures.”

The first three are perfluorocarbons, potent and long-lived greenhouse gases (GHGs.) SF₆ is Sulfur hexafluoride, and NF₃ is Nitrogen trifluoride. They’re both greenhouse gases with global warming potentials 23,500 times greater and 17,200 times greater than CO₂ over a 100-year period.

These artificial GHGs could be a technosignature of a civilization actively trying to warm their planet. They’re long-lived, have low toxicities, and have low false-positive potential. They also occur only in small amounts naturally. Their presence indicates industrial production.

“For us, these gases are bad because we don’t want to increase warming. But they’d be good for a civilization that perhaps wanted to forestall an impending ice age or terraform an otherwise-uninhabitable planet in their system, as humans have proposed for Mars,” said UCR astrobiologist and lead author Edward Schwieterman.

These chemicals could persist in an atmosphere for up to 50,000 years, making them near ideal for a civilization facing a freezing future. “They wouldn’t need to be replenished too often for a hospitable climate to be maintained,” Schwieterman said in a press release.

Unlike CFCs (chlorofluorocarbons), which damage the ozone layer, these chemicals are largely inert. Any civilization smart enough to engineer their atmosphere would avoid CFCs. CFCs also don’t last long in an oxygen atmosphere and wouldn’t be great technosignatures.

“If another civilization had an oxygen-rich atmosphere, they’d also have an ozone layer they’d want to protect,” Schwieterman said. “CFCs would be broken apart in the ozone layer even as they catalyzed its destruction.”

But from our ETI-seeking viewpoint, the best thing about the chemicals the researchers are studying is their prominent infrared signatures at extremely low concentrations.

“With an atmosphere like Earth’s, only one out of every million molecules could be one of these gases, and it would be potentially detectable,” Schwieterman said. “That gas concentration would also be sufficient to modify the climate.”

To understand these chemicals and their detectability, the research team simulated the atmosphere of TRAPPIST 1-f. This well-studied rocky exoplanet is in the habitable zone of a red dwarf star about 40 light-years away, making it a realistic observational target at that distance.

This study is based on the potential results of the LIFE telescope, which is still a concept. Its purpose is to examine the atmospheres of dozens of warm, terrestrial exoplanets. LIFE builds on telescope concepts from a couple of decades ago, like the European Space Agency’s Darwin spacecraft. Darwin wasn’t built, but the idea behind it was two-fold: to both find Earth-like exoplanets and to search for evidence of life.

Darwin was conceived as an interferometer, and so is LIFE. LIFE would have four separate space telescopes acting as one.

With LIFE, the GHGs would be easier to see than other standard biosignatures like O₂, O₃, CH₄, and N₂O. But unlike these chemicals, which can give false positives without a planetary context, the GHGs are more akin to technosignatures, which can be understood more independently from atmospheric chemistry. “In contrast to biosignatures, many technosignatures may provide greater specificity (less “false positive” potential), as many putative technosignatures have more limited abiotic formation channels when compared to biosignatures,” the authors explain in their research.

One desirable aspect of the search for these technosignature GHGs is that astronomers can find them as part of a general effort to study atmospheres.

“You wouldn’t need extra effort to look for these technosignatures, if your telescope is already characterizing the planet for other reasons,” said Schwieterman. “And it would be jaw-droppingly amazing to find them.”

This is not a futuristic scenario awaiting the development of new technology. We have the capability to do this soon, according to Daniel Angerhausen. Angerhausen is from the Swiss Federal Institute of Technology/PlanetS, a collaborating organization on LIFE.

“Our thought experiment shows how powerful our next-generation telescopes will be. We are the first generation in history that has the technology to systematically look for life and intelligence in our galactic neighborhood,” said Angerhausen.

“While all technosignature scenarios are speculative, we argue that it is unlikely fluorine-bearing technosignature gases will accumulate to detectable levels in a technosphere due only to inadvertent emission of industrial pollutants (or volcanic production),” the authors write.

They also explain that before individual GHG technosignatures were identified, anomalous MIR or NIR absorption signatures “… would be consistent with the presence of artificial greenhouse gases in a candidate technosphere.”

In their conclusion, they say that GHGs are viable technosignatures that can be found during routine exoplanet characterizations. “Both positive or negative results would meaningfully inform the search for life elsewhere,” they conclude.

{ https://www.universetoday.com/ }

28-06-2024 om 17:28 geschreven door peter  

One of the easiest ways to find exoplanets is using the transit method. It relies upon monitoring the brightness of a star which will then dim as a planet passes in front of it. It is of course possible that other objects could pass between us and a star; perhaps binary planets, tidally distorted planets, exocomets and, ready for it…. alien megastructures! A transit simulator has been created by a team of researchers and it can predict the brightness change from different transiting objects, even Dyson Swarms in construction. 

51 Pegasi-b was the first exoplanet discovered in 1995 and it sparked the development of numerous ground-based and space-based instruments. The launch of the Kepler Space Telescope and the Transiting Exoplanet Survey Satellite (TESS) in 2018 popularised the transit method, leading to the discovery of over 4,000 exoplanets. As instruments have become increasingly sensitive and precise, research has progressed from simply detecting exoplanets to studying their detailed characteristics.

Transit photometry has uncovered signatures of many interesting phenomena beyond the detection of exoplanets and eclipsing binaries. This technique has been instrumental in identifying features such as star-spots, and signatures of tidal interactions between host stars and exoplanets leading to significant growth in the sub-field of Asteroseismology

The study of transiting exoplanets and their timing variations has led to many discoveries. Non-transiting planets in distant solar systems have been found, orbital decay, disintegrating planets, exocomets and exomoon candidates has all been identified. Additionally, and perhaps of particular interest is that transit photometry has detected signals that have sparked interest in the search for technosignatures for the evidence of advanced civilizations.

It is important to note that no technosignatures have been confirmed yet but such signatures would not arise form natural processes and would demonstrate the presence of intelligent life. The signatures would come from a wide range of astroengineering projects like Dyson Spheres (a theoretical shell surrounding a star to capture its energy output) or the newly conceptualised Dyson Swarms (habitable satellites and energy collectors that orbit the star in formation. 

The research team led by Ushasi Bhowmick from the Indian based Space Application Centre has reported that they have developed a transit simulator that can not only generate light curves for exoplanets but also for any object of any size or shape! The simulation uses the Monte-Carlo technique that predicts all possible outcomes of an uncertain event. In this instance it can predict the light curve when an object of any shape or size transits across the disk of star. 

When the simulation was tested against actual exoplanet systems such as Trappist-1 it nicely predicted the light curve. It can also be used to model tidal distortions in binary star systems and even predict the light curve of non-natural objects such as the alien megastructures. The simulator has shown itself to be an invaluable method for understanding a wide range of transit phenomena. 

Source : 

• A General-Purpose Transit Simulator for Arbitrary Shaped Objects Orbiting Stars

{ https://www.universetoday.com/ }

28-06-2024 om 17:16 geschreven door peter  

The RASSOR 2.0 prototype had several design goals, but it’s probably most helpful to walk through a use-case scenario. According to the soil samples collected by Curiosity and other rovers, around 2% of the regolith on Mars is water, even in the relatively “dry” regions outside the poles. Collecting that water could help refuel rockets and supply settlements with drinking water, radiation shielding, or water for agriculture.

NASA commonly uses a mission structure involving four astronauts on a journey to Mars. In a paper describing the 2.0 version of the robot back in 2016, the authors, including Robert Mueller, the founder of the Swamp Works facility and a doyen of ISRU research, describe a mission structure that would see RASSOR mining 1,000,000 kg of Martian regolith per year and supplying 10,000 kilograms of oxygen to the mission.

To do so, it would utilize a lander with processing capabilities for separating the useful parts from the chaff and would trek from the lander site to the regolith collection site about 35 times a day. With a charging cycle that would take about 8 hours a day, that would leave upwards of 16 hours to continuously mine the surface of Mars for these valuable materials.

The paper goes on to describe the design process for the RASSOR’s various subsystems, including the powerful actuators that make up the majority of the weight of the system. They also used 3D-printed titanium to make the bucket drum excavating tools, which required some ingenious machining by Swamp Work’s machinists. 

But in the end, they did make a working prototype. They tested it with improvements like a 50% drop in weight and an autonomous mode that utilizes simple stereo-vision cameras. The team believes this project is ready to move on to the next phase, taking a step closer to making it a reality.

That paper, however, was published eight years ago. A relatively detailed internet search doesn’t produce any results for RASSOR 3.0 other than a brief mention at the end of the 2.0 paper. So, for now, it seems the project is on hold. However, another NASA project, the Lunabotics Challenge, keeps university teams working toward effectively mining regolith for us in ISRU systems. Maybe one of those teams will pick up where the RASSOR team left off – or come up with a completely new design. We’ll have to wait and see.

Learn More:

• Mueller et al. – Design of an Excavation Robot: Regolith Advanced Surface Systems Operations Robot (RASSOR) 2.0
• UT – Japan Tests Robotic Earth-Moving Equipment in a Simulated Lunar Jobsite
• UT – NASA Wants to Learn to Live Off the Land on the Moon
• UT – What is ISRU, and How Will it Help Human Space Exploration?

Lead Image:

• CAD model of the RASSOR 2.0 excavating robot.
  Credit – Mueller et al.

{ https://www.universetoday.com/ }

28-06-2024 om 00:27 geschreven door peter  

The next step would be to complete a full 3D model of the asteroid’s surface, followed by using a high-powered laser to force the dust off the surface and into a storage tank. In the storage tank, the dust would be pulverized even more, with a thruster motor pushing the dust out from the rover in a direction that causes thrust against the asteroid’s surface, thereby changing its orbit.

The dust thrust deflection would be monitored from Earth, and an orbiting probe would be used to close the loop. If necessary, several other autonomous rovers could make their way along the asteroid’s surface, coordinating their thrusting efforts to increase the deflection force. 

All this requires a lot of new technologies, coordination, and testing to become a reality. The authors suggest a potential test case to be ready for the close approach of Apophis in 2029. However, even if a lander is prepared and ready for that time, it could take upwards of 20 years for a perceptible deflection to happen – assuming that nothing goes wrong with the system in that time frame. Any engineer will tell you that having a system operate non-stop for 20 years is almost unheard of, though admittedly, some space probes are the exception to that.

One major advantage of this technique, though, would be its dual use as a proof of concept for asteroid deflection and mining. Many of the technologies would overlap, and there would be an incentive for governments and non-profits to invest in a potentially world-saving technology—at least more so than for them to invest in an as-yet unproven mining technology.

For now, this idea remains on the drawing board. But, if there is ever a real push to try out different methods of asteroid redirection, it could crop up again, especially if it’s supported by one of the major space agencies. And humanity might even get the benefit of a fully functional asteroid miner out of it.

Learn More:

• Santos et al. – Conceptual Design for Deflecting a Potentially Hazardous Asteroid with a Space Duster
• UT – How to Deflect an Asteroid with Today’s Technology
• UT – Asteroid Detection, Deflection Needs More Money, Report Says
• UT – If You’re Trying to Prevent an Asteroid Impact, the Technical and Political Challenges are Staggering

Lead Image:

• Artist’s conception of the mission architecture, including the asteroid space duster (ASD).
  Credit – Santos et al.

{ https://www.universetoday.com/ }

28-06-2024 om 00:19 geschreven door peter  

Your Body Is Awash In Microplastics — Should You Be Worried?

Microplastics are all around us. The real question is what harm do they actually do?

BY MICHAEL RICHARDSON, MEIRU WANG AND THE CONVERSATION

 

Kinga Krzeminska/Moment/Getty Images

When plastic trash is dumped in a landfill or the sea, it breaks down very slowly. Sunlight and waves cause the surface of the plastic to become brittle, and particles are shed into the environment. Collectively known as “small plastic particles,” they range in size from five millimeters or smaller (microplastics) to less than one-thousandth of a millimeter (nano plastics). The smallest can only be detected with special scientific instruments.

It remains unclear how microplastics and nanoplastics get inside living things, but several entry points have been suggested. For example, they might pass through the gut from food or drink contaminated with small plastic particles. Or they may be breathed in, or absorbed through the skin.

Our research suggests that, for some animals, nanoplastics are bad news. We injected plastic nanoparticles into chicken embryos. We found that the particles traveled quickly in the blood to all tissues, especially the heart, liver, and kidneys. They were also excreted by the embryonic kidneys.

We noticed, too, that plastic nanoparticles tend to stick to a certain type of stem cell in the embryo. These cells are essential for the normal development of the nervous system and other structures. Any damage to stem cells could put the development of the embryo in jeopardy.

We suspect that the chicken embryo stem cells have substances on their surface called “cell-adhesion molecules,” which stick to the polystyrene nanoparticles that we used. We are following up on this finding because when nanoplastics stick to cells and get inside them, they can cause cell death and even serious birth defects in chickens and mice.

Similar studies cannot, of course, be carried out on people, so it is not yet possible to say what the implications of our animal research are for humans. What we know is that nanoplastics are found in the blood of human beings, in other bodily fluids, and in several major organs and key body tissues.

In recent years, microplastics and nanoplastics have been found in the brains, hearts, and lungs of humans. They have been discovered in the arteries of people with arterial disease, suggesting they may be a potential risk factor for cardiovascular disease. And they have been detected in breast milk, the placenta, and, most recently, penises.

Chinese researchers reported earlier this year that they had found microplastics in human and dog testes. More recently, another Chinese team found microplastics in all 40 samples of human semen they tested. This follows an Italian study that found microplastics in six out of ten samples of human semen.

Our fear is that microplastics and nanoplastics might act in a similar way to deadly asbestos fibers. Like asbestos, they are not broken down in the body and can be taken up into cells, killing them and then being released to damage yet more cells.

Nanoplastics have even been found in breastmilk. 

Dzmitry Kliapitski / Alamy Stock Photo

REASSURING, FOR NOW

But there is a need for caution here. There is no evidence that nanoplastics can cross the placenta and get into the human embryo.

Also, even if nanoplastics do cross the placenta and in sufficient numbers to damage the embryo, we would expect to have seen a big increase in abnormal pregnancies in recent years. That is because the problem of plastic waste in the environment has been growing enormously over the years. But we are not aware of any evidence of a corresponding, large increase in birth defects or miscarriages.

That, for now, is reassuring.

It may be that microplastics and nanoplastics if they cause harm to our bodies, do so in a subtle way that we have not yet detected. Whatever the case, scientists are working hard to discover what the risks might be.

One promising avenue of research would involve the use of human placental tissue grown in the laboratory. Special artificial placenta tissues, called “trophoblast organoids,” have been developed to study how harmful substances cross the placenta.

Researchers are also investigating potentially beneficial uses for nanoplastics. Although they are not yet licensed for clinical use, the idea is that they could be used to deliver drugs to specific body tissues that need them. Cancer cells could, in this way, be targeted for destruction without damaging other healthy tissue.

Whatever the outcome of nanoplastics research, we and many other scientists will continue trying to find out what nanoplastics are doing to ourselves and the environment.

• This article was originally published on The Conversation by Michael Richardson and Meiru Wang at Leiden University. Read the original article here.

{ https://www.inverse.com/ }

27-06-2024 om 23:40 geschreven door peter  

Why the World of Humanoid Robots Is on Fire Right Now

It’s not just you — there’s a robot renaissance upon us.

BY JAMES PERO

 

Figure

THAT [OPTIMUS] IS SO HOT RIGHT NOW

A glut of humanoid robots was not on my 2024 bingo, but here we are. Every time I scroll through X, there’s something — for instance, a new partnership, an exciting demo, or whatever this is.

There are a lot of humanoid bots now and a lot more seemingly on the way — Figure’s AI robot, Unitree’s speed demon, Agility’s workhorse — but arguably most important of all is Tesla’s Optimus.

I don’t mean that Optimus is necessarily more advanced than the rest of the aforementioned — in fact, Tesla’s competition is pretty fierce right now — but Optimus has something that the other robots don’t: clout.

As some of you may already know, Elon Musk, despite Optimus’ nascency, has been bullish on the robot’s future. In fact, this year, Musk went as far as to suggest that Optimus could make Tesla a $25 trillion company. I know, I know...

If you’re rolling your eyes, you’re justified. Musk is often (and not infrequently wrongly) optimistic about future technologies. But his carnival barking is a huge asset, not just for Tesla, but for the prospects of functional, real-world humanoid robots writ large.

What I mean is that, for better or worse, since Tesla awkwardly introduced Optimus on stage last year with a weird interpretive dance, a lot has happened. When Tesla and Musk talk, people, regardless of their opinion of the pair, listen. If Musk says robots are on the way, maybe they actually are, and that added confidence gives other non-Tesla upstarts more opportunities as well.

While Musk and Tesla have paved the way with their own fuel to the humanoid robot fire, AI is an equally powerful hype train that is doing the same thing concurrently.

AI, specifically large language models (LLMs) like the ones that power ChatGPT, is opening up a world of possibilities for what people think humanoid robots are capable of. That means making them more collaborative, helping them understand commands more easily, and maybe more importantly, making them feel more human.

Take Figure’s robot, for example — in lots of ways, it functions like every other humanoid robot of its ilk. But when paired with ChatGPT, things start to look truly futuristic.

It’s crucial to take Figure’s demo with a grain of salt. Right now, chatbots have a way of making things look functional on the surface, but in practice, the results are rocky. But even as a proof of concept, it’s clear AI has a place in the humanoid robot future and there’s interest in figuring out what that place is.

And sure, being conversational isn’t as important as say, making a robot with the fine motor skills to fold a shirt properly, but if these things are going to be in your home, they better have some manners, right?

READY FOR THE SBOTLIGHT

There are obviously a lot more factors than just Tesla and AI at play when it comes to the popularity of humanoid robots. Research paved years ago by companies like Boston Dynamics and the prospect of bots’ applications in factories have been equally pivotal.

But this time around, humanoid robots feel as though they’ve found themselves in front of an even bigger and brighter spotlight; it’s not just Tesla that’s putting them there. Nvidia is getting in on the game, providing its own expertise with systems like GR00T which is meant to help robots train themselves. Similarly, OpenAI seems to be interested in the robotics game and there’s a job opening as proof.

It’s hard to say what will come of all the attention, but if history is an example, money and hype usually mean progress. And if that means I don’t have to haul my own dirty clothes to the laundromat, then consider me a humanoid robot truther.

{ https://www.inverse.com/ }

27-06-2024 om 23:28 geschreven door peter