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Astronomers Find Jupiter-like Cloud Bands on Closest Brown Dwarf
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By NASA
This illustration shows a red, early-universe dwarf galaxy that hosts a rapidly feeding black hole at its center. Using data from NASA’s James Webb Space Telescope and Chandra X-ray Observatory, a team of astronomers have discovered this low-mass supermassive black hole at the center of a galaxy just 1.5 billion years after the Big Bang. It is pulling in matter at a phenomenal rate — over 40 times the theoretical limit. While short lived, this black hole’s “feast” could help astronomers explain how supermassive black holes grew so quickly in the early universe.NOIRLab/NSF/AURA/J. da Silva/M. Zamani A rapidly feeding black hole at the center of a dwarf galaxy in the early universe, shown in this artist’s concept, may hold important clues to the evolution of supermassive black holes in general.
Using data from NASA’s James Webb Space Telescope and Chandra X-ray Observatory, a team of astronomers discovered this low-mass supermassive black hole just 1.5 billion years after the big bang. The black hole is pulling in matter at a phenomenal rate — over 40 times the theoretical limit. While short lived, this black hole’s “feast” could help astronomers explain how supermassive black holes grew so quickly in the early universe.
Supermassive black holes exist at the center of most galaxies, and modern telescopes continue to observe them at surprisingly early times in the universe’s evolution. It’s difficult to understand how these black holes were able to grow so big so rapidly. But with the discovery of a low-mass supermassive black hole feasting on material at an extreme rate so soon after the birth of the universe, astronomers now have valuable new insights into the mechanisms of rapidly growing black holes in the early universe.
The black hole, called LID-568, was hidden among thousands of objects in the Chandra X-ray Observatory’s COSMOS legacy survey, a catalog resulting from some 4.6 million Chandra observations. This population of galaxies is very bright in the X-ray light, but invisible in optical and previous near-infrared observations. By following up with Webb, astronomers could use the observatory’s unique infrared sensitivity to detect these faint counterpart emissions, which led to the discovery of the black hole.
The speed and size of these outflows led the team to infer that a substantial fraction of the mass growth of LID-568 may have occurred in a single episode of rapid accretion.
LID-568 appears to be feeding on matter at a rate 40 times its Eddington limit. This limit relates to the maximum amount of light that material surrounding a black hole can emit, as well as how fast it can absorb matter, such that its inward gravitational force and outward pressure generated from the heat of the compressed, infalling matter remain in balance.
These results provide new insights into the formation of supermassive black holes from smaller black hole “seeds,” which current theories suggest arise either from the death of the universe’s first stars (light seeds) or the direct collapse of gas clouds (heavy seeds). Until now, these theories lacked observational confirmation.
The new discovery suggests that “a significant portion of mass growth can occur during a single episode of rapid feeding, regardless of whether the black hole originated from a light or heavy seed,” said International Gemini Observatory/NSF NOIRLab astronomer Hyewon Suh, who led the research team.
A paper describing these results (“A super-Eddington-accreting black hole ~1.5 Gyr after the Big Bang observed with JWST”) appears in the journal Nature Astronomy.
About the Missions
NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
Read more from NASA’s Chandra X-ray Observatory.
Learn more about the Chandra X-ray Observatory and its mission here:
https://www.nasa.gov/chandra
https://chandra.si.edu
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Elizabeth Laundau
NASA Headquarters
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202-923-0167
elizabeth.r.landau@nasa.gov
Lane Figueroa
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
lane.e.figueroa@nasa.gov
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By NASA
4 min read
Final Venus Flyby for NASA’s Parker Solar Probe Queues Closest Sun Pass
On Wednesday, Nov. 6, 2024, NASA’s Parker Solar Probe will complete its final Venus gravity assist maneuver, passing within 233 miles (376 km) of Venus’ surface. The flyby will adjust Parker’s trajectory into its final orbital configuration, bringing the spacecraft to within an unprecedented 3.86 million miles of the solar surface on Dec. 24, 2024. It will be the closest any human made object has been to the Sun.
Parker’s Venus flybys have become boons for new Venus science thanks to a chance discovery from its Wide-Field Imager for Parker Solar Probe, or WISPR. The instrument peers out from Parker and away from the Sun to see fine details in the solar wind. But on July 11, 2020, during Parker’s third Venus flyby, scientists turned WISPR toward Venus in hopes of tracking changes in the planet’s thick cloud cover. The images revealed a surprise: A portion of WISPR’s data, which captures visible and near infrared light, seemed to see all the way through the clouds to the Venusian surface below.
“The WISPR cameras can see through the clouds to the surface of Venus, which glows in the near-infrared because it’s so hot,” said Noam Izenberg, a space scientist at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland.
Venus, sizzling at approximately 869 degrees Fahrenheit (about 465 C), was radiating through the clouds.
The WISPR images from the 2020 flyby, as well as the next flyby in 2021, revealed Venus’ surface in a new light. But they also raised puzzling questions, and scientists have devised the Nov. 6 flyby to help answer them.
Left: A series of WISPR images of the nightside of Venus from Parker Solar Probe’s fourth flyby showing near infrared emissions from the surface. In these images, lighter shades represent warmer temperatures and darker shades represent cooler. Right: A combined mosaic of radar images of Venus’ surface from NASA’s Magellan mission, where the brightness indicates radar properties from smooth (dark) to rough (light), and the colors indicate elevation from low (blue) to high (red). The Venus images correspond well with data from the Magellan spacecraft, showing dark and light patterns that line up with surface regions Magellan captured when it mapped Venus’ surface using radar from 1990 to 1994. Yet some parts of the WISPR images appear brighter than expected, hinting at extra information captured by WISPR’s data. Is WISPR picking up on chemical differences on the surface, where the ground is made of different material? Perhaps it’s seeing variations in age, where more recent lava flows added a fresh coat to the Venusian surface.
“Because it flies over a number of similar and different landforms than the previous Venus flybys, the Nov. 6 flyby will give us more context to evaluate whether WISPR can help us distinguish physical or even chemical properties of Venus’ surface,” Izenberg said.
After the Nov. 6 flyby, Parker will be on course to swoop within 3.8 million miles of the solar surface, the final objective of the historic mission first conceived over 65 years ago. No human-made object has ever passed this close to a star, so Parker’s data will be charting as-yet uncharted territory. In this hyper-close regime, Parker will cut through plumes of plasma still connected to the Sun. It is close enough to pass inside a solar eruption, like a surfer diving under a crashing ocean wave.
“This is a major engineering accomplishment,” said Adam Szabo, project scientist for Parker Solar Probe at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
The closest approach to the Sun, or perihelion, will occur on Dec. 24, 2024, during which mission control will be out of contact with the spacecraft. Parker will send a beacon tone on Dec. 27, 2024, to confirm its success and the spacecraft’s health. Parker will remain in this orbit for the remainder of its mission, completing two more perihelia at the same distance.
Parker Solar Probe is part of NASA’s Living with a Star program to explore aspects of the Sun-Earth system that directly affect life and society. The Living with a Star program is managed by the agency’s Goddard Space Flight Center in Greenbelt, Maryland, for NASA’s Science Mission Directorate in Washington. The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, manages the Parker Solar Probe mission for NASA and designed, built, and operates the spacecraft.
By Miles Hatfield
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Nov 04, 2024 Related Terms
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By NASA
New Zealand’s stunning scenery has famously provided the backdrop for fictional worlds in fantasy films. A unique cloud that forms over the Otago region of the country’s South Island also evokes the otherworldly, while very much existing in reality.NASA/Lauren Dauphin; USGS Landsat 8’s Operational Land Imager acquired this image of an elongated lenticular cloud, locally nicknamed the “Taieri Pet,” above New Zealand’s South Island on Sept. 7, 2024. Lenticular clouds form when prevailing winds encounter a topographic barrier, such as a mountain range. Wind that is forced to flow up and over the mountains creates a kind of wave in the atmosphere. Air cools at the crest of the wave, and the water vapor it contains condenses into clouds.
Image credit: NASA/Lauren Dauphin; USGS
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By NASA
4 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
The Permafrost Tunnel north of Fairbanks, Alaska, was dug in the 1960s and is run by the U.S. Army’s Cold Regions Research and Engineering Laboratory. It is the site of much research into permafrost — ground that stays frozen throughout the year, for multiple years.NASA/Kate Ramsayer Earth’s far northern reaches have locked carbon underground for millennia. New research paints a picture of a landscape in change.
A new study, co-authored by NASA scientists, details where and how greenhouse gases are escaping from the Earth’s vast northern permafrost region as the Arctic warms. The frozen soils encircling the Arctic from Alaska to Canada to Siberia store twice as much carbon as currently resides in the atmosphere — hundreds of billions of tons — and most of it has been buried for centuries.
An international team, led by researchers at Stockholm University, found that from 2000 to 2020, carbon dioxide uptake by the land was largely offset by emissions from it. Overall, they concluded that the region has been a net contributor to global warming in recent decades in large part because of another greenhouse gas, methane, that is shorter-lived but traps significantly more heat per molecule than carbon dioxide.
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Greenhouse gases shroud the globe in this animation showing data from 2021. Carbon dioxide is shown in orange; methane is shown in purple. Methane traps heat 28 times more effectively than carbon dioxide over a 100-year timescale. Wetlands are a significant source of such emissions.NASA’s Scientific Visualization Studio The findings reveal a landscape in flux, said Abhishek Chatterjee, a co-author and scientist at NASA’s Jet Propulsion Laboratory in Southern California. “We know that the permafrost region has captured and stored carbon for tens of thousands of years,” he said. “But what we are finding now is that climate-driven changes are tipping the balance toward permafrost being a net source of greenhouse gas emissions.”
Carbon Stockpile
Permafrost is ground that has been permanently frozen for anywhere from two years to hundreds of thousands of years. A core of it reveals thick layers of icy soils enriched with dead plant and animal matter that can be dated using radiocarbon and other techniques. When permafrost thaws and decomposes, microbes feed on this organic carbon, releasing some of it as greenhouse gases.
Unlocking a fraction of the carbon stored in permafrost could further fuel climate change. Temperatures in the Arctic are already warming two to four times faster than the global average, and scientists are learning how thawing permafrost is shifting the region from being a net sink for greenhouse gases to becoming a net source of warming.
They’ve tracked emissions using ground-based instruments, aircraft, and satellites. One such campaign, NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE), is focused on Alaska and western Canada. Yet locating and measuring emissions across the far northern fringes of Earth remains challenging. One obstacle is the vast scale and diversity of the environment, composed of evergreen forests, sprawling tundra, and waterways.
This map, based on data provided by the National Snow and Ice Data Center, shows the extent of Arctic permafrost. The amount of permafrost underlying the surface ranges from continuous — in the coldest areas — to more isolated and sporadic patches.NASA Earth Observatory Cracks in the Sink
The new study was undertaken as part of the Global Carbon Project’s RECCAP-2 effort, which brings together different science teams, tools, and datasets to assess regional carbon balances every few years. The authors followed the trail of three greenhouse gases — carbon dioxide, methane, and nitrous oxide — across 7 million square miles (18 million square kilometers) of permafrost terrain from 2000 to 2020.
Researchers found the region, especially the forests, took up a fraction more carbon dioxide than it released. This uptake was largely offset by carbon dioxide emitted from lakes and rivers, as well as from fires that burned both forest and tundra.
They also found that the region’s lakes and wetlands were strong sources of methane during those two decades. Their waterlogged soils are low in oxygen while containing large volumes of dead vegetation and animal matter — ripe conditions for hungry microbes. Compared to carbon dioxide, methane can drive significant climate warming in short timescales before breaking down relatively quickly. Methane’s lifespan in the atmosphere is about 10 years, whereas carbon dioxide can last hundreds of years.
The findings suggest the net change in greenhouse gases helped warm the planet over the 20-year period. But over a 100-year period, emissions and absorptions would mostly cancel each other out. In other words, the region teeters from carbon source to weak sink. The authors noted that events such as extreme wildfires and heat waves are major sources of uncertainty when projecting into the future.
Bottom Up, Top Down
The scientists used two main strategies to tally greenhouse gas emissions from the region. “Bottom-up” methods estimate emissions from ground- and air-based measurements and ecosystem models. Top-down methods use atmospheric measurements taken directly from satellite sensors, including those on NASA’s Orbiting Carbon Observatory-2 (OCO-2) and JAXA’s (Japan Aerospace Exploration Agency)Greenhouse Gases Observing Satellite.
Regarding near-term, 20-year, global warming potential, both scientific approaches aligned on the big picture but differed in magnitude: The bottom-up calculations indicated significantly more warming.
“This study is one of the first where we are able to integrate different methods and datasets to put together this very comprehensive greenhouse gas budget into one report,” Chatterjee said. “It reveals a very complex picture.”
News Media Contacts
Jane J. Lee / Andrew Wang
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0307 / 626-379-6874
jane.j.lee@jpl.nasa.gov / andrew.wang@jpl.nasa.gov
Written by Sally Younger
2024-147
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Last Updated Oct 29, 2024 Related Terms
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By European Space Agency
An international team of astronomers has used the NASA/ESA/CSA James Webb Space Telescope to detect the first brown dwarf candidates outside the Milky Way in the star cluster NGC 602.
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