This infrared image from NASA’s James Webb Space Telescope was taken by the onboard Near-Infrared Camera for the JWST Advanced Deep Extragalactic Survey, or JADES, program. The NIRCam data was used to determine which galaxies to study further with spectroscopic observations. One such galaxy, JADES-GS-z14-0 (shown in the pullout), was determined to be at a redshift of 14.3, making it the current record-holder for most distant known galaxy. This corresponds to a time less than 300 million years after the big bang. Credit NASA, ESA, CSA, STScI, Brant Robertson (UC Santa Cruz), Ben Johnson (CfA), Sandro Tacchella (Cambridge), Marcia Rieke (University of Arizona), Daniel Eisenstein (CfA), Phill Cargile (CfA)
March 11, 2025
By Eurasia Review
University of Arizona astronomers have learned more about a surprisingly mature galaxy that existed when the universe was just less than 300 million years old – just 2% of its current age.
Observed by NASA’s James Webb Space Telescope, the galaxy – designated JADES-GS-z14-0 – is unexpectedly bright and chemically complex for an object from this primordial era, the researchers said. This provides a rare glimpse into the universe’s earliest chapter.
The findings, published in the journal Nature Astronomy, build upon the researchers’ previous discovery, reported in 2024, of JADES-GS-z14-0 as the most distant galaxy ever observed. While the initial discovery established the galaxy’s record-breaking distance and unexpected brightness, this new research delves deeper into its chemical composition and evolutionary state.
The work was done as part of the JWST Advanced Deep Extragalactic Survey, or JADES, a major James Webb Space Telescope program designed to study distant galaxies.
This wasn’t simply stumbling upon something unexpected, said Kevin Hainline, co-author of the new study and an associate research professor at the U of A Steward Observatory. The survey was deliberately designed to find distant galaxies, but this one broke the team’s records in ways they didn’t anticipate – it was intrinsically bright and had a complex chemical composition that was totally unexpected so early in the universe’s history.
“It’s not just a tiny little nugget. It’s bright and fairly extended for the age of the universe when we observed it,” Hainline said.
“The fact that we found this galaxy in a tiny region of the sky means that there should be more of these out there,” said lead study author Jakob Helton, a graduate researcher at Steward Observatory. “If we looked at the whole sky, which we can’t do with JWST, we would eventually find more of these extreme objects.”
The research team used multiple instruments on board JWST, including the Near Infrared Camera, or NIRCam, whose construction was led by U of A Regents Professor of Astronomy Marcia Rieke. Another instrument on the telescope – the Mid-Infrared Instrument, or MIRI, revealed something extraordinary: significant amounts of oxygen.
In astronomy, anything heavier than helium is considered a “metal,” Helton said. Such metals require generations of stars to produce. The early universe contained only hydrogen, helium and trace amounts of lithium. But the discovery of substantial oxygen in the JADES-GS-z14-0 galaxy suggests the galaxy had been forming stars for potentially 100 million years before it was observed.
To make oxygen, the galaxy must have started out very early on, because it would have had to form a generation of stars, said George Rieke, Regents Professor of Astronomy and the study’s senior author. Those stars must have evolved and exploded as supernovae to release oxygen into interstellar space, from which new stars would form and evolve.
“It’s a very complicated cycle to get as much oxygen as this galaxy has. So, it is genuinely mind boggling,” Rieke said.
The finding suggests that star formation began even earlier than scientists previously thought, which pushes back the timeline for when the first galaxies could have formed after the Big Bang.
The observation required approximately nine days of telescope time, including 167 hours of NIRCam imaging and 43 hours of MIRI imaging, focused on an incredibly small portion of the sky.
The U of A astronomers were lucky that this galaxy happened to sit in the perfect spot for them to observe with MIRI. If they had pointed the telescope just a fraction of a degree in any direction, they would have missed getting this crucial mid-infrared data, Helton said.
“Imagine a grain of sand at the end of your arm. You see how large it is on the sky – that’s how large we looked at,” Helton said.
The existence of such a developed galaxy so early in cosmic history serves as a powerful test case for theoretical models of galaxy formation.
“Our involvement here is a product of the U of A leading in infrared astronomy since the mid-’60s, when it first started. We had the first major infrared astronomy group over in the Lunar and Planetary lab, with Gerard Kuiper, Frank Low and Harold Johnson,” Rieke said.
As humans gain the ability to directly observe and understand galaxies that existed during the universe’s infancy, it can provide crucial insights into how the universe evolved from simple elements to the complex chemistry necessary for life as we know it.
“We’re in an incredible time in astronomy history,” Hainline said. “We’re able to understand galaxies that are well beyond anything humans have ever found and see them in many different ways and really understand them. That’s really magic.”
Climate Change Will Reduce Number Of Satellites That Can Safely Orbit In Space
March 11, 2025
By Eurasia Review
MIT aerospace engineers have found that greenhouse gas emissions are changing the environment of near-Earth space in ways that, over time, will reduce the number of satellites that can sustainably operate there.
In a study that will appear in Nature Sustainability, the researchers report that carbon dioxide and other greenhouse gases can cause the upper atmosphere to shrink. An atmospheric layer of special interest is the thermosphere, where the International Space Station and most satellites orbit today. When the thermosphere contracts, the decreasing density reduces atmospheric drag— a force that pulls old satellites and other debris down to altitudes where they will encounter air molecules and burn up.
Less drag therefore means extended lifetimes for space junk, which will litter sought-after regions for decades and increase the potential for collisions in orbit.
The team carried out simulations of how carbon emissions affect the upper atmosphere and orbital dynamics, in order to estimate the “satellite carrying capacity” of low-Earth orbit. These simulations predict that by the year 2100, the carrying capacity of the most popular regions could be reduced by 50-66 percent due to the effects of greenhouse gases.
“Our behavior with greenhouse gases here on Earth over the past 100 years is having an effect on how we operate satellites over the next 100 years,” says study author Richard Linares, associate professor in MIT’s Department of Aeronautics and Astronautics (AeroAstro).
“The upper atmosphere is in a fragile state as climate change disrupts the status quo,” adds lead author William Parker, a graduate student in AeroAstro. “At the same time, there’s been a massive increase in the number of satellites launched, especially for delivering broadband internet from space. If we don’t manage this activity carefully and work to reduce our emissions, space could become too crowded, leading to more collisions and debris.”
The study includes co-author Matthew Brown of the University of Birmingham.
Sky fall
The thermosphere naturally contracts and expands every 11 years in response to the sun’s regular activity cycle. When the sun’s activity is low, the Earth receives less radiation, and its outermost atmosphere temporarily cools and contracts before expanding again during solar maximum.
In the 1990s, scientists wondered what response the thermosphere might have to greenhouse gases. Their preliminary modeling showed that, while the gases trap heat in the lower atmosphere, where we experience global warming and weather, the same gases radiate heat at much higher altitudes, effectively cooling the thermosphere. With this cooling, the researchers predicted that the thermosphere should shrink, reducing atmospheric density at high altitudes.
In the last decade, scientists have been able to measure changes in drag on satellites, which has provided some evidence that the thermosphere is contracting in response to something more than the sun’s natural, 11-year cycle.
“The sky is quite literally falling — just at a rate that’s on the scale of decades,” Parker says. “And we can see this by how the drag on our satellites is changing.”
The MIT team wondered how that response will affect the number of satellites that can safely operate in Earth’s orbit. Today, there are over 10,000 satellites drifting through low-Earth orbit, which describes the region of space up to1,200 miles, or 2,000 kilometers, from Earth’s surface. These satellites deliver essential services, including internet, communications, navigation, weather forecasting, and banking. The satellite population has ballooned in recent years, requiring operators to perform regular collision-avoidance maneuvers to keep safe. Any collisions that do occur can generate debris that remains in orbit for decades or centuries, increasing the chance for follow-on collisions with satellites, both old and new.
“More satellites have been launched in the last five years than in the preceding 60 years combined,” Parker says. “One of key things we’re trying to understand is whether the path we’re on today is sustainable.”
Crowded shells
In their new study, the researchers simulated different greenhouse gas emissions scenarios over the next century to investigate impacts on atmospheric density and drag. For each “shell,” or altitude range of interest, they then modeled the orbital dynamics and the risk of satellite collisions based on the number of objects within the shell. They used this approach to identify each shell’s “carrying capacity” — a term that is typically used in studies of ecology to describe the number of individuals that an ecosystem can support.
“We’re taking that carrying capacity idea and translating it to this space sustainability problem, to understand how many satellites low-Earth orbit can sustain,” Parker explains.
The team compared several scenarios: one in which greenhouse gas concentrations remain at their level from the year 2000 and others where emissions change according to the Intergovernmental Panel on Climate Change (IPCC) Shared Socioeconomic Pathways (SSPs). They found that scenarios with continuing increases in emissions would lead to a significantly reduced carrying capacity throughout low-Earth orbit.
In particular, the team estimates that by the end of this century, the number of satellites safely accommodated within the altitudes of 200 and 1,000 kilometers could be reduced by 50 to 66 percent compared with a scenario in which emissions remain at year-2000 levels. If satellite capacity is exceeded, even in a local region, the researchers predict that the region will experience a “runaway instability,” or a cascade of collisions that would create so much debris that satellites could no longer safely operate there.
Their predictions forecast out to the year 2100, but the team says that certain shells in the atmosphere today are already crowding up with satellites, particularly from recent “megaconstellations” such as SpaceX’s Starlink, which comprises fleets of thousands of small internet satellites.
“The megaconstellation is a new trend, and we’re showing, because of climate change, we’re going to have a reduced capacity in orbit,” Linares says. “And in local regions, we’re close to approaching this capacity value today.”
“We rely on the atmosphere to clean up our debris. And if the atmosphere is changing, then the debris environment will change too,” Parker adds. “We show the long-term outlook on orbital debris is critically dependent on curbing our greenhouse gas emissions.”
This research is supported in part by the U.S. National Science Foundation, the U.S. Air Force, and the U.K. Natural Environment Research Council.
NASA Receives Some Data Before Intuitive Machines Ends Lunar Mission
Intuitive Machines’ IM-2 captured an image March 6, 2025, after landing in a crater from the Moon’s South Pole. The lunar lander is on its side about 820 feet from the intended landing site, Mons Mouton. In the center of the image between the two lander legs is the Polar Resources Ice Mining Experiment 1 suite, which shows the drill deployed. Credit: Intuitive Machines
Shortly after touching down inside a crater on the Moon, carrying NASA technology and science on its IM-2 mission, Intuitive Machines collected some data for the agency before calling an early end of mission at 12:15 a.m. CST Friday.
As part of the company’s second Moon delivery for NASA under the agency’s CLPS (Commercial Lunar Payload Services) initiative and Artemis campaign, the IM-2 mission included a drill to bring lunar soil to the surface and a mass spectrometer to look for the presence of volatiles, or gases, that could one day help provide fuel or breathable oxygen to future Artemis explorers.
Planned to land at Mons Mouton, IM-2 touched down at approximately 11:30 a.m. March 6, more than 1,300 feet (400 meters) from its intended landing site. Intuitive Machines said images collected later confirmed the lander was on its side, preventing it from fully operating the drill and other instruments before its batteries were depleted.
The IM-2 mission landed closer to the lunar South Pole than any previous lander.
“Our targeted landing site near the lunar South Pole is one of the most scientifically interesting, and geographically challenging locations, on the Moon,” said Nicky Fox, associate administrator for science at NASA Headquarters in Washington. “Each success and setback are opportunities to learn and grow, and we will use this lesson to propel our efforts to advance science, exploration, and commercial development as we get ready for human exploration of Mars.”
The Nova-C lander, named Athena, captured and transmitted images of the landing site before activating the technology and science instruments. Among the data collected, NASA’s PRIME-1 (Polar Resources Ice Mining Experiment 1) suite, which includes the lunar drill known as TRIDENT (The Regolith and Ice Drill for Exploring New Terrain), successfully demonstrated the hardware’s full range of motion in the harsh environment of space. The Mass Spectrometer Observing Lunar Operations (MSOLO) as part of the PRIME-1 suite of instruments, detected elements likely due to the gases emitted from the lander’s propulsion system.
“While this mission didn’t achieve all of its objectives for NASA, the work that went into the payload development is already informing other agency and commercial efforts,” said Clayton Turner, associate administrator for space technology, NASA Headquarters. “As we continue developing new technologies to support exploration of the Moon and Mars, testing technologies in-situ is crucial to informing future missions. The CLPS initiative remains an instrumental method for achieving this.”
Despite the lander’s configuration, Intuitive Machines, which was responsible for launch, delivery, and surface operations under its CLPS contract, was able to complete some instrument checkouts and collect 250 megabytes of data for NASA.
“Empowering American companies to deliver science and tech to the Moon on behalf of NASA both produces scientific results and continues development of a lunar economy,” said Joel Kearns, deputy associate administrator for Exploration in the Science Mission Directorate at NASA Headquarters. “While we’re disappointed in the outcome of the IM-2 mission, we remain committed to supporting our commercial vendors as they navigate the very difficult task of landing and operating on the Moon.”
NASA’s Laser Retroreflector Array, a passive instrument meant to provide a reference point on the lunar surface and does not power on, will remain affixed to the top deck of the lander. Although Intuitive Machines’ Nova-C Hopper and Nokia’s 4G/LTE Tipping Point technologies, funded in part by NASA, were only able to complete some objectives, they provided insight into maturing technologies ready for infusion into a commercial space application including some checkouts in flight and on the surface.
Intuitive Machines’ IM-2 mission launched at 6:16 p.m., Feb. 26, aboard a SpaceX Falcon 9 rocket from Launch Complex 39A at the agency’s Kennedy Space Center in Florida.
Intuitive Machines has two more deliveries on the books for NASA in the future, with its IM-3 mission slated for 2026, and IM-4 mission in 2027.
To date, five vendors have been awarded a total of 11 lunar deliveries under CLPS and are sending more than 50 instruments to various locations on the Moon, including the Moon’s far side and South Pole region. CLPS contracts are indefinite-delivery/indefinite-quantity contracts with a cumulative maximum contract value of $2.6 billion through 2028.
Eurasia Review is an independent Journal that provides a venue for analysts and experts to disseminate content on a wide-range of subjects that are often overlooked or under-represented by Western dominated media.
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