Just thought I'd commemorate the fact that today marks 25 years since I took my Geology 104 lab exam at Cal State Long Beach. Today was a turning point in how I would view my remaining years in college after I spent one last class with Yenny (who I called 'Denise' in my Blog for how many years after that); giving her a Christmas card and us exchanging e-mail addresses that would lead to 2001 being one of the most painful years of my life.
Anyways, click on this Blog Entry to read what I originally posted about this day a quarter century ago. Have a nice Saturday!
NASA, ESA, STScI, D. Jewitt (UCLA), M.-T. Hui (Shanghai Astronomical Observatory). Image Processing: J. DePasquale (STScI)
NASA’s Hubble Space Telescope Revisits Interstellar Comet (News Release - December 4)
NASA’s Hubble Space Telescope reobserved interstellar comet 3I/ATLAS on November 30, with its Wide Field Camera 3 instrument. At the time, the comet was about 178 million miles (286 million kilometers) from Earth.
Hubble tracked the comet as it moved across the sky. As a result, background stars appear as streaks of light.
Hubble previously observed 3I/ATLAS in July, shortly after its discovery, and a number of NASA missions have since studied the comet as well. Observations are expected to continue for several more months as 3I/ATLAS heads out of the Solar System.
NASA Completes Nancy Grace Roman Space Telescope Construction (News Release)
NASA’s next big eye on the cosmos is now fully assembled. On November 25, technicians joined the inner and outer portions of the Nancy Grace Roman Space Telescope in the largest clean room at the agency’s Goddard Space Flight Center in Greenbelt, Maryland.
“Completing the Roman observatory brings us to a defining moment for the agency,” said NASA Associate Administrator Amit Kshatriya. “Transformative science depends on disciplined engineering, and this team has delivered—piece by piece, test by test—an observatory that will expand our understanding of the Universe. As Roman moves into its final stage of testing following integration, we are focused on executing with precision and preparing for a successful launch on behalf of the global scientific community.”
After final testing, Roman will move to the launch site at NASA’s Kennedy Space Center in Florida for launch preparations in summer 2026. Roman is slated to launch by May 2027, but the team is on track for launch as early as fall 2026. A SpaceX Falcon Heavy rocket will send the observatory to its final destination a million miles from Earth.
“With Roman’s construction complete, we are poised at the brink of unfathomable scientific discovery,” said Julie McEnery, Roman’s senior project scientist at NASA Goddard. “In the mission’s first five years, it’s expected to unveil more than 100,000 distant worlds, hundreds of millions of stars, and billions of galaxies. We stand to learn a tremendous amount of new information about the Universe very rapidly after Roman launches.”
Observing from space will make Roman very sensitive to infrared light — light with a longer wavelength than our eyes can see — from far across the cosmos. Pairing its crisp infrared vision with a sweeping view of space will allow astronomers to explore myriad cosmic topics, from dark matter and dark energy to distant worlds and solitary black holes, and conduct research that would take hundreds of years using other telescopes.
“Within our lifetimes, a great mystery has arisen about the cosmos: why the expansion of the Universe seems to be accelerating. There is something fundamental about space and time we don’t yet understand, and Roman was built to discover what it is,” said Nicky Fox, associate administrator, Science Mission Directorate, NASA Headquarters in Washington. “With Roman now standing as a complete observatory, which keeps the mission on track for a potentially early launch, we are a major step closer to understanding the Universe as never before. I couldn’t be prouder of the teams that have gotten us to this point.”
Double vision
Roman is equipped with two instruments: the Wide Field Instrument and Coronagraph Instrument technology demonstration.
The coronagraph will demonstrate new technologies for directly imaging planets around other stars. It will block the glare from distant stars and make it easier for scientists to see the faint light from planets in orbit around them. The Coronagraph aims to photograph worlds and dusty disks around nearby stars in visible light to help us see giant worlds that are older, colder, and in closer orbits than the hot, young super-Jupiters direct imaging has mainly revealed so far.
“The question of ‘Are we alone?’ is a big one, and it’s an equally big task to build tools that can help us answer it,” said Feng Zhao, the Roman Coronagraph Instrument manager at NASA’s Jet Propulsion Laboratory in Southern California. “The Roman Coronagraph is going to bring us one step closer to that goal. It’s incredible that we have the opportunity to test this hardware in space on such a powerful observatory as Roman.”
The coronagraph team will conduct a series of pre-planned observations for three months spread across the mission’s first year-and-a-half of operations, after which the mission may conduct additional observations based on scientific community input.
The Wide Field Instrument is a 288-megapixel camera that will unveil the cosmos all the way from our Solar System to near the edge of the observable Universe. Using this instrument, each Roman image will capture a patch of the sky bigger than the apparent size of a full moon. The mission will gather data hundreds of times faster than NASA’s Hubble Space Telescope, adding up to 20,000 terabytes (20 petabytes) over the course of its five-year primary mission.
“The sheer volume of the data Roman will return is mind-boggling and key to a host of exciting investigations,” said Dominic Benford, Roman’s program scientist at NASA Headquarters.
Survey trifecta
Using the Wide Field Instrument, Roman will conduct three core surveys which will account for 75% of the primary mission. The High-Latitude Wide-Area Survey will combine the powers of imaging and spectroscopy to unveil more than a billion galaxies strewn across a wide swath of space and time. Astronomers will trace the evolution of the Universe to probe dark matter — invisible matter detectable only by how its gravity affects things we can see — and trace the formation of galaxies and galaxy clusters over time.
The High-Latitude Time-Domain Survey will probe our dynamic Universe by observing the same region of the cosmos repeatedly. Stitching these observations together to create movies will allow scientists to study how celestial objects and phenomena change over time periods of days to years. That will help astronomers study dark energy — the mysterious cosmic pressure thought to accelerate the Universe’s expansion — and could even uncover entirely new phenomena that we don’t yet know to look for.
Roman’s Galactic Bulge Time-Domain Survey will look inward to provide one of the deepest views ever of the heart of our Milky Way galaxy. Astronomers will watch hundreds of millions of stars in search of microlensing signals — gravitational boosts of a background star’s light caused by the gravity of an intervening object. While astronomers have mainly discovered star-hugging worlds, Roman’s microlensing observations can find planets in the habitable zone of their star and farther out, including worlds like every planet in our Solar System except Mercury.
Microlensing will also reveal rogue planets—worlds that roam the galaxy untethered to a star — and isolated black holes. The same dataset will reveal 100,000 worlds that transit, or pass in front of, their host stars.
The remaining 25% of Roman’s five-year primary mission will be dedicated to other observations that will be determined with input from the broader scientific community. The first such program, called the Galactic Plane Survey, has already been selected.
Because Roman’s observations will enable such a wide range of science, the mission will have a General Investigator Program designed to support astronomers to reveal scientific discoveries using Roman data. As part of NASA’s commitment to Gold Standard Science, NASA will make all of Roman’s data publicly available with no exclusive use period. This ensures that multiple scientists and teams can use data at the same time, which is important since every Roman observation will address a wealth of science cases.
Roman’s namesake — Dr. Nancy Grace Roman, NASA’s first chief astronomer — made it her personal mission to make cosmic vistas readily accessible to all by paving the way for telescopes based in space.
“The mission will acquire enormous quantities of astronomical imagery that will permit scientists to make groundbreaking discoveries for decades to come, honoring Dr. Roman’s legacy in promoting scientific tools for the broader community,” said Jackie Townsend, Roman’s deputy project manager at NASA Goddard. “I like to think Dr. Roman would be extremely proud of her namesake telescope and thrilled to see what mysteries it will uncover in the coming years.”
The Nancy Grace Roman Space Telescope is managed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA’s Jet Propulsion Laboratory in Southern California; Caltech/IPAC in Pasadena, California; the Space Telescope Science Institute in Baltimore; and a science team comprising scientists from various research institutions. The primary industrial partners are BAE Systems Inc. in Boulder, Colorado; L3Harris Technologies in Rochester, New York; and Teledyne Scientific & Imaging in Thousand Oaks, California.
NASA / Goddard / University of Arizona / Dan Gallagher
Sugars, ‘Gum,’ Stardust Found in NASA’s Asteroid Bennu Samples (News Release)
The asteroid Bennu continues to provide new clues to scientists’ biggest questions about the formation of the early Solar System and the origins of life. As part of the ongoing study of pristine samples delivered to Earth by NASA’s OSIRIS-REx(Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) spacecraft, three new papers published Tuesday by the journals Nature Geoscience and Nature Astronomy present remarkable discoveries: sugars essential for biology, a gum-like substance not seen before in astromaterials, and an unexpectedly high abundance of dust produced by supernova explosions.
Sugars essential to life
Scientists led by Yoshihiro Furukawa of Tohoku University in Japan found sugars essential for biology on Earth in the Bennu samples, detailing their findings in the journal Nature Geoscience. The five-carbon sugar ribose and, for the first time in an extraterrestrial sample, six-carbon glucose were found. Although these sugars are not evidence of life, their detection, along with previous detections of amino acids, nucleobases, and carboxylic acids in Bennu samples, show that building blocks of biological molecules were widespread throughout the Solar System.
For life on Earth, the sugars deoxyribose and ribose are key building blocks of DNA and RNA, respectively. DNA is the primary carrier of genetic information in cells. RNA performs numerous functions, and life as we know it could not exist without it.
Ribose in RNA is used in the molecule’s sugar-phosphate “backbone” that connects a string of information-carrying nucleobases. “All five nucleobases used to construct both DNA and RNA, along with phosphates, have already been found in the Bennu samples brought to Earth by OSIRIS-REx,” said Furukawa. “The new discovery of ribose means that all of the components to form the molecule RNA are present in Bennu.”
The discovery of ribose in asteroid samples is not a complete surprise. Ribose has previously been found in two meteorites recovered on Earth. What is important about the Bennu samples is that researchers did not find deoxyribose.
If Bennu is any indication, this means that ribose may have been more common than deoxyribose in environments of the early Solar System. Researchers think the presence of ribose and lack of deoxyribose supports the “RNA world” hypothesis, where the first forms of life relied on RNA as the primary molecule to store information and to drive chemical reactions necessary for survival.
“Present day life is based on a complex system organized primarily by three types of functional biopolymers: DNA, RNA, and proteins,” explains Furukawa. “However, early life may have been simpler. RNA is the leading candidate for the first functional biopolymer because it can store genetic information and catalyze many biological reactions.”
The Bennu samples also contained one of the most common forms of “food” (or energy) used by life on Earth, the sugar glucose, which is the first evidence that an important energy source for life as we know it was also present in the early Solar System.
Mysterious, ancient ‘gum’
A second paper, in the journal Nature Astronomy led by Scott Sandford at NASA’s Ames Research Center in California’s Silicon Valley and Zack Gainsforth of the University of California, Berkeley, reveals a gum-like material in the Bennu samples never seen before in space rocks – something that could have helped set the stage on Earth for the ingredients of life to emerge. The surprising substance was likely formed in the early days of the Solar System, as Bennu’s young parent asteroid warmed.
Once soft and flexible, but since hardened, this ancient “space gum” consists of polymer-like materials extremely rich in nitrogen and oxygen. Such complex molecules could have provided some of the chemical precursors that helped trigger life on Earth, and finding them in the pristine samples from Bennu is important for scientists studying how life began and whether it exists beyond our planet.
Bennu’s ancestral asteroid formed from materials in the solar nebula – the rotating cloud of gas and dust that gave rise to the Solar System – and contained a variety of minerals and ices. As the asteroid began to warm, due to natural radiation, a compound called carbamate formed through a process involving ammonia and carbon dioxide. Carbamate is water soluble, but it survived long enough to polymerize, reacting with itself and other molecules to form larger and more complex chains impervious to water.
The carbamate process suggests that it formed before the parent body warmed enough to become a watery environment.
“With this strange substance, we’re looking at, quite possibly, one of the earliest alterations of materials that occurred in this rock,” said Sandford. “On this primitive asteroid that formed in the early days of the Solar System, we’re looking at events near the beginning of the beginning.”
Using an infrared microscope, Sandford’s team selected unusual, carbon-rich grains containing abundant nitrogen and oxygen. They then began what Sandford calls “blacksmithing at the molecular level,” using the Molecular Foundry at Lawrence Berkeley National Laboratory (Berkeley Lab) in Berkeley, California. Applying ultra-thin layers of platinum, they reinforced a particle, welded on a tungsten needle to lift the tiny grain, and shaved the fragment down using a focused beam of charged particles.
When the particle was a thousand times thinner than a human hair, they analyzed its composition via electron microscopy at the Molecular Foundry and X-ray spectroscopy at Berkeley Lab’s Advanced Light Source. The ALS’s high-spatial resolution and sensitive X-ray beams enabled unprecedented chemical analysis.
“We knew we had something remarkable the instant the images started to appear on the monitor,” said Gainsforth. “It was like nothing we had ever seen, and for months we were consumed by data and theories as we attempted to understand just what it was and how it could have come into existence.”
The team conducted a slew of experiments to examine the material’s characteristics. As the details emerged, the evidence suggested that the strange substance had been deposited in layers on grains of ice and minerals present in the asteroid.
It was also flexible – a pliable material, similar to used gum or even a soft plastic. Indeed, during their work with the samples, researchers noticed that the strange material was bendy and dimpled when pressure was applied. The stuff was translucent, and exposure to radiation made it brittle, like a lawn chair left too many seasons in the Sun.
“Looking at its chemical makeup, we see the same kinds of chemical groups that occur in polyurethane on Earth,” said Sandford, “making this material from Bennu something akin to a ‘space plastic.’”
The ancient asteroid stuff isn’t simply polyurethane, though, which is an orderly polymer. This one has more “random, hodgepodge connections and a composition of elements that differs from particle to particle,” said Sandford. But the comparison underscores the surprising nature of the organic material discovered in NASA’s asteroid samples, and the research team aims to study more of it.
By pursuing clues about what went on long ago, deep inside an asteroid, scientists can better understand the young Solar System – revealing the precursors to and ingredients of life that it already contained, and how far those raw materials may have been scattered, thanks to asteroids much like Bennu.
Abundant supernova dust
Another paper in the journal Nature Astronomy, led by Ann Nguyen of NASA’s Johnson Space Center in Houston, analyzed presolar grains – dust from stars predating our Solar System – found in two different rock types in the Bennu samples to learn more about where its parent body formed and how it was altered by geologic processes. It is believed that presolar dust was generally well-mixed as our Solar System formed. The samples had six-times the amount of supernova dust than any other studied astromaterial, suggesting the asteroid’s parent body formed in a region of the protoplanetary disk enriched in the dust of dying stars.
The study also reveals that, while Bennu’s parent asteroid experienced extensive alteration by fluids, there are still pockets of less-altered materials within the samples that offer insights into its origin.
“These fragments retain a higher abundance of organic matter and presolar silicate grains, which are known to be easily destroyed by aqueous alteration in asteroids,” said Nguyen. “Their preservation in the Bennu samples was a surprise and illustrates that some material escaped alteration in the parent body. Our study reveals the diversity of presolar materials that the parent accreted as it was forming.”
