UFO'S of UAP'S, ASTRONOMIE, RUIMTEVAART, ARCHEOLOGIE, OUDHEIDKUNDE, SF-SNUFJES EN ANDERE ESOTERISCHE WETENSCHAPPEN

The Space Telescope Science Institute (STScI) has announced the science objectives for Webb's General Observer Programs in Cycle 4 (Cycle 4 GO) program. The Cycle 4 observations include 274 programs that establish the science program for JWST's fourth year of operations, amounting to 8,500 hours of prime observing time. This is a significant increase from Cycle 3 observations and the 5,500 hours of prime time and 1,000 hours of parallel time it entailed.

These programs are broken down into eight categories, ranging from exoplanet habitability and the earliest galaxies in the Universe to supermassive black holes, stellar evolution, and Solar System astronomy. They were selected by the Cycle 4 Telescope Allocation Committee (TAC) in February 2025, which comprised two Executive Committee Chairs, 36 Panel Chairs and Vice Chairs, 183 Discussion Panelists, 315 External Panelists, and 220 Expert Reviewers.

In terms of exoplanet studies, the observation programs for Cycle 4 focus on exoplanet characterization, formation, and dynamics. In particular, the programs address ongoing questions about exoplanet habitability and the types of stars that can host habitable planets. For instance, program GO 7068, titled "Surveying Stellar Shenanigans: Exploring M dwarf Flares for Exoplanetary Insights," focuses on the question of red dwarf stars and the hazards posed by their flare activity.

The field of exoplanets has undergone a major transition in recent years. With over 5,800 confirmed candidates (5,849 as of the writing of this article), scientists are moving from the discovery process to characterization. This consists of obtaining spectra from exoplanet atmospheres to determine what chemical signatures are present. By detecting potential biosignatures (i.e., oxygen, carbon dioxide, water, methane, etc.), scientists can measure planetary habitability more accurately.

Interestingly, the JWST was not originally designed for exoplanet characterization. However, its extreme sensitivity to infrared (IR) wavelengths and advanced spectrometers mean that Webb can obtain transit spectra from exoplanets as they pass in front of their suns. Combined with its coronographs (which block out light from a system's star), it can also detect the faint light reflected by exoplanet atmospheres and surfaces.

Red Dwarfs

In the past decade, astronomers have detected numerous rocky planets orbiting nearby M-type (red dwarf) stars. Of the 30 potentially habitable exoplanets closest to Earth, 28 orbit red dwarf stars. This is particularly good news for astronomers and astrobiologists since red dwarf stars are the most common in the Universe and account for about 75% of stars in the Milky Way. What's more, research has indicated that there may be tens of billions of potentially habitable rocky planets orbiting red dwarf stars in the Milky Way.

On the other hand, red dwarf stars are also known for being variable and prone to significant flare activity compared to Sun-like stars. Recent studies have detected several "superflares" events from red dwarfs powerful enough to remove the atmospheres of any planets orbiting them. However, recent observations by the Transiting Exoplanet Survey Satellite (TESS) have shown that red dwarf stars tend to emit superflares from their poles, thus sparing orbiting planets.

Learning more about M-type stars and their effects on planetary habitability is the purpose of GO 7068, "Surveying Stellar Shenanigans: Exploring M dwarf Flares for Exoplanetary Insights." Dhvani Doshi, a PhD student at McGill University's Trottier Institute for Research on Exoplanets, is the principal investigator of this program. Using Webb's Near Infrared Imager and Slitless Spectrograph (NIRISS) instrument, the team will observe five active M-type stars for 5 to 10 hours each to obtain spectra as they transit in front of their stars.

They also anticipate recording 400 flare events with energies exceeding 10^{30} erg, or 6.24^42 electronvolts (ev). Per the program description:

"Through detailed analysis of flare properties and behavior in the NIR regime, our proposal aims to address critical gaps in our understanding of stellar flare phenomena on M dwarfs, refining existing models and enhancing our ability to interpret exoplanetary spectra in the presence of stellar activity."

Direct Imaging

As noted, Webb's advanced instruments also make it uniquely qualified for Direct Imaging studies. These involve observing exoplanets directly as they orbit their suns, which was previously restricted to massive planets with wide orbits. Thanks to Webb's extreme sensitivity and advanced instruments, Cycle 4 GO includes several programs that will conduct DI studies of nearby exoplanets.

This is the purpose of the GO 6915 program, titled "Direct Detection and Characterization of a Nearby Temperate Giant Planet." The Principal Investigator of this program is William Balmer, a Ph.D. candidate at Johns Hopkins University and the Space Telescope Science Institute (STScI). He and his colleagues propose directly imaging HD 22237 b using Webb's Near Infrared Camera (NIRCam) and Mid-Infrared Imager (MIRI) coronographs.

This nearby gas giant is about 37 light-years from Earth and is 5.19 Jupiter masses. As the team described in their proposal:

"These observations will constrain key atmospheric model uncertainties, like the strength of water-ice cloud opacity, the abundance of ammonia, and the strength of disequilibrium chemistry in the planet's atmosphere. This program is designed to efficiently detect the planet at high confidence, photometrically characterize the atmosphere, and refine the planet's sky-projected orbit ahead of Cycle 5; doing so will allow the community to estimate the feasibility of follow-up spectroscopy on the fastest timescale."

Another interesting program is GO 7612, "We can directly image super-Earth-sized planets near the habitable zone of Sirius B with JWST/MIRI." The PI for this program is Logan Pearce, a postdoctoral researcher from the University of Michigan. The team will conduct a direct imaging campaign using Webb's Mid-Infrared Imager and its coronagraph to search for super-earths and cold gas planets near the outer edge of Sirius B's habitable zone (HZ).

Located 8.7 light-years away, Sirius B - the companion star of Sirius A (an A-type main sequence white star) - is the closest white dwarf to the Solar System. For decades, scientists have wondered if white dwarf stars can support habitable planets. In recent years, research has indicated that planets would need to orbit closely to white dwarfs to be in their HZs. Similar to exoplanets that orbit M-type stars, rocky planets orbiting in the HZs of white dwarfs are likely to be tidally locked, with one side absorbing potentially dangerous levels of radiation.

"Our program holds the potential to detect rocky planets and cold (>70K) gas giants—a feat unlikely to be possible until the next generation of observatories comes online decades from now. If a planet-like signal is detected, follow-up proper motion measurements or spectroscopy will confirm its planetary nature and provide a detailed characterization of its physical and atmospheric properties. This program could be JWST's singular chance to directly image rocky planets in a nearby system, offering profound insights into planetary evolution around post-main sequence stars and in binary systems."

Rocky Exoplanets

In terms of exoplanet studies, Webb is also especially qualified for studying smaller, rocky planets that orbit more closely to their suns - which is where Earth-like planets are likely to reside. This presents astronomers with the exciting opportunity to examine Earth-like planets near the Solar System more closely. This includes the closest exoplanet to the Solar System, which is the purpose of the GO 7251 program, "Does Our Closest M-Dwarf Rocky Neighbor Have An Atmosphere? We Need to Find Out."

The rocky neighbor in question is LTT 1445A b, the nearest transiting rocky planet considered the most likely to have an atmosphere. The planet is a Super-Earth that orbits the primary star in a triple M-dwarf system located 22 light-years away. The planet's size (1.3 Earth radii and 2.73 Earth masses) and its equilibrium temperature (150.85 °C; 303.5 °F) are promising indications that it may have an atmosphere.

Artist's impression of a Super-Earth. Credit: NASA

The program will follow up on recent observations made by the Hubble Space Telescope (HST) that obtained accurate measurements of the planet's size. While previous observations were made using Webb, the planet's proximity to its host star saturated most of its near-infrared observing modes. But thanks to the implementation of the NIRCam Short-Wavelength Grism Time Series, astronomers can now observe LTT1445A b without risk of saturation.

Katherine Bennett, a Ph.D. student in Planetary Sciences at Johns Hopkins University, is the program's principal investigator. Their planned observations will monitor LTT1445A b during eight transits using the NIRCam Grism Time Series template. As Bennet and her colleagues indicated in the program description:

"We note that LTT1445Ab's hotter and smaller sibling, LTT 1445Ac, is being targeted by the STScI Rocky Worlds DDT Program. By coupling the DDT emission photometry study with our NIRCam transmission spectroscopy study, we can map the presence of atmospheres within a single system. What's more, if LTT 1445Ab does not have an atmosphere, this would have profound implications for M-dwarf habitability in general."

Similarly, program GO 7875 ("The only known atmosphere on a rocky exoplanet?") will dedicate observation time to 55 Cancri e. This Super-Earth, located 41 light-years away, measures 1.875 Earth radii and has a mass 7.99 times that of Earth. Its close orbit to 55 Cancri A means it is extremely hot, with an estimated equilibrium temperature of 2000 K (1725 °C; 3140 °F). This has led astronomers to theorize that the entire planet is covered in an ocean of lava.

While not a good candidate for astrobiology studies, it is currently the only rocket exoplanet with evidence of an atmosphere. The program's principal investigator is Michael Zhang, an Inaugural E. Margaret Burbidge Prize Postdoctoral Fellow at the University of Chicago. This program will conduct MIRI MRS observations of the exoplanet during three eclipses, which will allow them to confirm the existence of an atmosphere, obtain spectra, and constrain its carbon dioxide abundance. Per the program description:

"As an old, ultra-hot (Teq=2000 K), and ultra-short-period planet, 55 Cnc e may seem a-priori like a particularly hostile place for any gaseous envelope. Understanding whether and/or how such an envelope exists on 55 Cnc e, the most observationally favorable super-Earth, has strong implications for the survivability of rocky planet atmospheres more generally."

Another exciting program is GO 7953, "Exo-Geology: Surface Spectral Features from a Rocky Exoplanet." Led by PI Kimberly Paragas, a graduate student in the Planetary Science option at the California Institute of Technology (Caltech). This program will leverage the JWST's capabilities to conduct the very first spectroscopic characterization of a rocky exoplanet's surface.

This program will observe LHS 3844 b, a Super-Earth orbiting an M-type star 49 light-years from Earth. This exoplanet is considered the most promising surface characterization target in the exoplanet census. "This will allow us to leverage the vast expertise developed for Solar System rocky bodies to establish a new field of 'exo-geology' whose goal is to explore the geological histories and mantle compositions of rocky exoplanets is to explore the geological histories and mantle compositions of rocky exoplanets," states the team in their proposal.

Planet Formation

The Cycle 4 General Observations will also use Webb's IR imaging capabilities to explore how planets form from debris disks. This will address key questions in astrobiology, not the least of which is how habitable planets evolve. To this end, program GO 6940, "Determining the Origin of Water Ice in the Beta Pictoris Debris Disk," was selected as part of Cycle Four. This campaign is led by PI Sarah Betti, an STScI postdoctoral fellow.

This program will use Webb's Near-Infrared Spectrometer (NIRSpec) and spectrograph to obtain medium-resolution spectroscopy to resolve water and carbon dioxide ices in the Beta Pictoris debris disk. Recent spectrometric observations have the presence of ices across the whole disk for the first time in a debris disk, including a hint of a significant ice population at its outer edge. These grains were not expected to survive, leading to a shift in scientists' understanding of debris disk chemistry.

This discovery also raised new questions about the role of giant collisions in producing the observed ice grains. As a result, the characterization of the origin and composition of these ices is vital to our understanding of late-stage planet formation and ice transport in disks. To this end, this program aims to conduct MIRI spectroscopy of the system's disk to resolve frozen volatiles, allowing astronomers to learn more about how planet formation occurs in debris disks.

"By mapping the whole dust clump, we can uncover the origin, chemical composition, and thermal history of the ices in this disk," per the program proposal.

These programs offer a small taste of what the JWST will study during this observation cycle. In addition to exoplanet studies, teams from around the world will use observation time to learn more about a wealth of cosmological phenomena and unresolved questions in astronomy, astrophysics, astrobiology, cosmology, and planetary geology.

Further Reading:

STScI

Earlier this week, the Space Telescope Science Institute (STScI) announced the science objectives for the fourth cycle of the James Webb Space Telescope's (JWST) General Observations program - aka. Cycle 4 GO. This latest cycle includes 274 programs that will make up the JWST's fourth year of operations, amounting to 8,500 hours of prime observing time. These programs are broken down into eight categories that encompass Webb's capabilities.

This includes exoplanet study and characterization, the study of the earliest galaxies in the Universe, stellar populations and formation, and Solar System Astronomy. As we addressed in the previous installment, Cycle 4 includes many programs that will leverage Webb's extreme sensitivity and advanced instruments to observe exoplanets, characterize their atmospheres, and measure their potential habitability.

In keeping with Webb's major science objectives, many of the Cycle 4 programs will also focus on studying the earliest stars and galaxies in the Universe. These programs will build on previous efforts to observe high-redshift galaxies (those that formed shortly after the Big Bang), the first population of stars in the Universe (Population III), and examine the role Dark Matter (DM) played in their formation.

Central to this is the cosmological period known as the "Cosmic Dark Ages," which occurred between 370,000 and 1 billion years after the Big Bang. During this time, the Universe was permeated by neutral hydrogen, and there were only two main sources of photons: the relic radiation left over from the Big Bang - the Cosmic Microwave Background (CMB) - and those occasionally released by neutral hydrogen atoms.

This period is also when the first stars and galaxies are believed to have formed (ca. 13.6 billion years ago). This led to the gradual ionization of the clouds of neutral hydrogen, which led to the "Epoch of Reionization," which led to the Universe becoming "transparent" (visible to modern instruments). Cosmologists refer to the period where the first galaxies emerged from the Dark Ages as “Cosmic Dawn."

Previous instruments lacked the resolution or sensitivity to capture light from this epoch, which is shifted into parts of the infrared spectrum that are very difficult to observe. However, Webb's sensitivity and infrared optics allow astronomers to finally pierce the veil of the "Dark Ages."

The Planck legacy, inflation and the origin of structure in the universe

High Redshift Galaxies

The earliest galaxies in the Universe are designated "high redshift," which refers to how the wavelength of their light has become elongated due to the expansion of the Universe ((aka. the Hubble-Lemaitre Constant). This causes the light to become "shifted" towards the red end of the spectrum. Light from galaxies that existed during the early Universe (more than 13 billion years ago) is redshifted to the point where it is only visible in the infrared spectrum.

This is the purpose of the GO 7208 program, titled "THRIFTY: The High-RedshIft FronTier surveY." This observation campaign will build on JWST's detection of several luminous galaxies with redshift values greater than 9 (z>9). This corresponds to galaxies that existed up to 13.5 billion years ago, one of Webb's greatest discoveries to date. The abundance of galaxies this early in the Universe and their apparent brightness was a surprise to astronomers and has led to a revision of theories on early galaxy formation.

Possible explanations include modifications to the Lambda Cold Dark Matter (LCDM) model of cosmology, the possibility that SMBHs may have been super-luminous in this period, the rapid formation of stars from abundant cold gas clouds, feedback-free starbursts, and more. However, confirmation of these theories requires more direct evidence, which the THRIFTY program hopes to address.

The program's PI is Romain Meyer, a postdoctoral researcher at the University of Geneva (UNIGE). As he and his team described in their GO 7208 program proposal, "THRIFTY will determine the true number density of ultra-luminous galaxies at z>9 by targeting a sample of 123 candidates selected from >1 million sources over a total of 0.3 square degrees (out of the Galactic plane) from all existing prime and pure-parallel JWST imaging surveys."

One of Webb's earliest discoveries from Cycle 1 was of a population of small, red-tinted galaxies during the early Universe that may have contained growing SMBHs. These "Little Red Dots" (LRDs), as they were nicknamed, were thought to be Active Galactic Nuclei (AGNs), or quasars, but many astronomers. While they were declared one of the biggest discoveries in physics in 2023, there is still no consensus on what they actually are.

Enter the GO 7404 program, titled "How I wonder what you are -- do JWST's Little Red Dots twinkle? Testing broad-line and continuum variability on week, month, and six-month." Rohan Naidu, a NASA Hubble Fellow and the Pappalardo Fellow in Physics at the Massachusetts Institute of Technology (MIT), is this program's Principal Investigator (PI). Using Webb's Near-Infrared Camera (NIRCam), they will conduct the first longwave systematic LRD monitoring campaign to determine their exact nature.

Next, there's the GO 7814 program, titled "MINERVA: Unlocking the Hidden Gems of the Distant Universe and Completing HST and JWST’s Imaging Legacy with Medium Bands." This program, led by PI Dr. Adam Muzzin of York University, will build on the deep imaging surveys conducted with the JWST Near-Infrared Camera (NIRCam). While revolutionary, these surveys were limited to broad-band observations with low spectral resolution.

Little red objects from JADES, CEERS, PRIMER, UNCOVER and NGDEEP Surveys. Credit: NASA, ESA, CSA, STScI, Dale Kocevski (Colby College)

For their program, they will use Webb's Mid-Infrared Instrument (MIRI) to examine the primary fields observed by the Hubble Space Telescope (HST) and the JWST. In the process, they plan to increase the surveyed area nearly by a factor of 10 compared to existing medium-band programs, leading to the discovery of rare and previously undetected populations in existing deep-field catalogs.

These observations, they state, will allow them to:

"efficiently identify and characterize galaxies with unusual SEDs including z>12 candidates, high-redshift Balmer breaks, metal-poor extreme emission line galaxies, and extremely red/dusty sources,
improve stellar mass and star-formation rate density measurements at 2 < z < 10 by factors of 2-4, and
create resolved maps of stellar mass and star formation across 10 Gyr of cosmic time to model galaxy growth in two dimensions."

Epoch of Reionization

In addition to the earliest galaxies, one of Webb's biggest objectives is the detection of the first stars in the Universe. These Population III stars are believed to have been ultra-hot, massive, and short-lived, remaining in their main sequence phase for a few dozen million years. They also emitted tremendous amounts of ultraviolet radiation, which led to the "Epoch of Reionization" (EoR). Until the deployment of the JWST, this population of stars remained entirely theoretical.

This is the reason for programs like GO 7677, "Pushing the Faintest Limits: Extremely Low-Luminosity and Pop III-like Star-Forming Complexes in the Early Universe." Using the JWST's NIRSpec integral field unit (IFU), the team - led by Eros Vanzella, a First Researcher of the INAF Astrophysics and Space Science Observatory in Bologna - will observe two stars at z=5.663 and z=4.194, corresponding to distances of 11.7 billion and 11.425 billion light-years away. As they state in their proposal:

"This study will allow us to measure the metallicity of both sources and assess the presence of massive stars in such elusive systems by evaluating their ionizing photon production efficiency. These observations will expand (at least double) the sample of ultra-faint sources with these measurements which only JWST can perform, pushing the frontier of understanding toward Population III-like star formation conditions. The fortunate angular proximity of the two targets allows for simultaneous observation within the same IFU field of views."

There's also the GO 7436 program, "The Last Neutral Islands at the End of Reionization? Characterizing the Nature of the Longest Dark Gaps in IGM Transmission at z~5.3." During this cosmic epoch, ionized regions gradually grew and overlapped in the intergalactic medium. However, how and when it took place is still unknown, and placing accurate estimates is crucial to studying the formation of galaxies in the early Universe. It is led by PI Xiangyu Jin, a graduate student with the Stewart Observatory at the University of Arizona.

He and his team plan to use the JWST to observe galaxies with redshifts of around z=5.5, corresponding to distances of about 12.4 billion light-years away. At this point, roughly 1.4 billion years after the Big Bang, the intergalactic medium (IGM) appears highly ionized to modern instruments, but "dark gaps" have still been observed. "These long dark gaps could be the last remaining neutral islands in the IGM at the end of a highly inhomogeneous reionization process," they propose. "If confirmed, it will have a profound impact on the physics of reionization."

To this end, they propose observations using the W. M. Keck Observatory and Webb's NIRCam. While the Keck observations will probe the Lyman-alpha emissions from roughly 230 galaxies (about 75 in the "dark gap" regions), NIRCam Wide Field Slitless Spectroscopy (WFSS) will conduct redshift measurements of these galaxies. "We will also characterize the galaxy density field around long dark gaps," they added. "This joint program will allow us to directly test the ultra-late reionization model and to place robust constraints on the topology of reionization and the nature of inhomogeneous reionization."

Schematic representation of the view into cosmic history provided by the bright light of distant quasars. Credit: Carnegie Institution for Science/MPIA

Then there's GO 8018, titled "DIVER: Deep Insights into UV Spectroscopy at the Epoch of Reionization." Led by PI Xiaojing Lin, a graduate student with the University of Arizona Steward Observatory. , this program will build on Webb's early observations of the EoR. These revealed hard radiation fields and bursts of star formation that were sometimes accompanied by the detection of extreme conditions in the interstellar medium (ISM) and unusual chemical abundance.

According to Lin and her colleagues, high-quality rest-frame UV spectroscopy of galaxies during this period is urgently needed. The team proposes conducting a deep spectroscopic survey of over 140 galaxies in the Great Observatories Origins Deep Survey North (GOODS-N) field at redshifts of z=5 to 9 (12.469 to 13.11 billion light years away). As the team wrote, this will establish the largest and deepest UV spectral database for EoR galaxies:

"DIVER will directly (1) clock the star formation history by determining the distribution and redshift evolution of carbon abundance and (2) probe the prevalence of extremely high electron density and its connection to bursty star formation and chemical peculiarity. DIVER will also lead to various high-profile science, including the UV demographics of AGNs and massive stellar populations, and constraining the reionization history through LyA. With great legacy values, DIVER will advance our understanding of star formation and chemical enrichment history in the early Universe, providing a crucial foundation for studies of z>10 galaxies."

Dark Matter Halos

According to the Standard Model of Cosmology - the Lambda Cold Dark Matter (LCDM) model - Dark Matter (DM) played a vital role in the formation of galaxies in the early Universe. In theory, DM halos (DMHs) formed from the gravitational collapse of density perturbations after the Big Bang and provided the gravitational "wells" that allowed clouds of gas to form Population III stars and the first galaxies. Like many other aspects of the early Universe, this process has remained entirely theoretical until this point.

The purpose behind the GO 7519 program, "How do dark matter halos connect with supermassive black holes and their host galaxies?" is to address the role these played in galaxy formation. Previous observations with Webb have played an important role in measuring the mass of DMHs in high-redshift quasars, but these measurements were limited to bright quasars. Per their proposal, the team will rely on NIRCam WFSS observations to identify emission lines from doubly ionized oxygen (O III) around 12 faint quasars at distances of about 12.716 billion light-years.

"In this new effort, we will measure the average DMH mass from the cross-correlation analysis of quasars and surrounding [O III] emitters and evaluate the DMH mass probability density function for individual quasars based on cosmological simulations. This program will allow us, for the first time, to obtain a quasar sample in which the black hole mass, stellar mass, and halo mass are all measured simultaneously. This sample will reveal their lifetime and the scaling relations in the early universe, underlying the SMBH growth of SMBHs over cosmic time."

For decades, astronomers, astrophysicists, and cosmologists have had to contend with limitations on what they could see within the cosmos. Thanks to the Hubble Space Telescope, they were able to observe galaxies that existed about 1 billion years after the Big Bang. Thanks to missions like the COsmic microwave Background Explorer (COBE), the Wilkinson Microwave Anisotropy Probe (WMAP), and Planck, they were able to measure the earliest light in the Universe.

Thanks to the JWST, scientists are now able to get a look at what came in between. By observing galaxies and cosmic structures as they existed shortly after the Big Bang, we may someday be able to chart cosmic evolution all the way back to the beginning of time.

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