A soot-like cloud is revealed in a section of the sky in this May 1, 2025, image from NASA’S SPHEREx space observatory. On May 1, SPHEREx began regular science operations, which consist of taking about 3,600 images per day for the next two years to provide new insights about the origins of the universe, galaxies, and the ingredients for life in the Milky Way. The observatory won’t be the first to map the entire sky, but it will be the first to do so in so many colors. It observes 102 wavelengths, or colors, of infrared light, which are undetectable to the human eye.
When SPHEREx takes a picture of the sky, the light is sent to six detectors that each produces a unique image capturing different wavelengths of light. These groups of six images are called an exposure, and SPHEREx takes about 600 exposures per day. When it’s done with one exposure, the whole observatory shifts position — the mirrors and detectors don’t move as they do on some other telescopes.
For the first time, astronomers have probed the physical environment of repeating X-ray outbursts near monster black holes thanks to data from NASA’s NICER (Neutron star Interior Composition Explorer) and other missions.
Scientists have only recently encountered this class of X-ray flares, called QPEs, or quasi-periodic eruptions. A system astronomers have nicknamed Ansky is the eighth QPE source discovered, and it produces the most energetic outbursts seen to date. Ansky also sets records in terms of timing and duration, with eruptions every 4.5 days or so that last approximately 1.5 days.
“These QPEs are mysterious and intensely interesting phenomena,” said Joheen Chakraborty, a graduate student at the Massachusetts Institute of Technology in Cambridge. “One of the most intriguing aspects is their quasi-periodic nature. We’re still developing the methodologies and frameworks we need to understand what causes QPEs, and Ansky’s unusual properties are helping us improve those tools.”
Watch how astronomers used data from NASA’s NICER (Neutron star Interior Composition Explorer) to study a mysterious cosmic phenomenon called a quasi-periodic eruption, or QPE. NASA’s Goddard Space Flight Center
Ansky’s name comes from ZTF19acnskyy, the moniker of a visible-light outburst seen in 2019. It was located in a galaxy about 300 million light-years away in the constellation Virgo. This event was the first indication that something unusual might be happening.
A paper about Ansky, led by Chakraborty, was published Tuesday in The Astrophysical Journal.
A leading theory suggests that QPEs occur in systems where a relatively low-mass object passes through the disk of gas surrounding a supermassive black hole that holds hundreds of thousands to billions of times the Sun’s mass.
When the lower-mass object punches through the disk, its passage drives out expanding clouds of hot gas that we observe as QPEs in X-rays.
Scientists think the eruptions’ quasi-periodicity occurs because the smaller object’s orbit is not perfectly circular and spirals toward the black hole over time. Also, the extreme gravity close to the black hole warps the fabric of space-time, altering the object’s orbits so they don’t close on themselves with each cycle. Scientists’ current understanding suggests the eruptions repeat until the disk disappears or the orbiting object disintegrates, which may take up to a few years.
A system astronomers call Ansky, in the galaxy at the center of this image, is home to a recently discovered series of quasi-periodic eruptions.
Sloan Digital Sky Survey
“Ansky’s extreme properties may be due to the nature of the disk around its supermassive black hole,” said Lorena Hernández-García, an astrophysicist at the Millennium Nucleus on Transversal Research and Technology to Explore Supermassive Black Holes, the Millennium Institute of Astrophysics, and University of Valparaíso in Chile. “In most QPE systems the supermassive black hole likely shreds a passing star, creating a small disk very close to itself. In Ansky’s case, we think the disk is much larger and can involve objects farther away, creating the longer timescales we observe.”
Hernández-García, in addition to being a co-author on Chakraborty’s paper, led the study that discovered Ansky’s QPEs, which was published in April in Nature Astronomy and used data from NICER, NASA’s Neil Gehrels Swift Observatory and Chandra X-ray Observatory, as well as ESA’s (European Space Agency’s) XMM-Newton space telescope.
NICER’s position on the International Space Station allowed it to observe Ansky about 16 times every day from May to July 2024. The frequency of the observations was critical in detecting the X-ray fluctuations that revealed Ansky produces QPEs.
Chakraborty’s team used data from NICER and XMM-Newton to map the rapid evolution of the ejected material driving the observed QPEs in unprecedented detail by studying variations in X-ray intensity during the rise and fall of each eruption.
The researchers found that each impact resulted in about a Jupiter’s worth of mass reaching expansion velocities around 15% of the speed of light.
The NICER (Neutron star Interior Composition Explorer) X-ray telescope is reflected on NASA astronaut and Expedition 72 flight engineer Nick Hague’s spacesuit helmet visor in this high-flying “space-selfie” taken during a spacewalk on Jan. 16, 2025.
NASA/Nick Hague
The NICER telescope’s ability to frequently observe Ansky from the space station and its unique measurement capabilities also made it possible for the team to measure the size and temperature of the roughly spherical bubble of debris as it expanded.
“All NICER’s Ansky observations used in these papers were collected after the instrument experienced a ‘light leak’ in May 2023,” said Zaven Arzoumanian, the mission’s science lead at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Even though the leak – which was patched in January – affected the telescope’s observing strategy, NICER was still able to make vital contributions to time domain astronomy, or the study of changes in the cosmos on timescales we can see.”
After the repair, NICER continued observing Ansky to explore how the outbursts have evolved over time. A paper about these results, led by Hernández-García and co-authored by Chakraborty, is under review.
Observational studies of QPEs like Chakraborty’s will also play a key role in preparing the science community for a new era of multimessenger astronomy, which combines measurements using light, elementary particles, and space-time ripples called gravitational waves to better understand objects and events in the universe.
One goal of ESA’s future LISA (Laser Interferometer Space Antenna) mission, in which NASA is a partner, is to study extreme mass-ratio inspirals — or systems where a low-mass object orbits a much more massive one, like Ansky. These systems should emit gravitational waves that are not observable with current facilities. Electromagnetic studies of QPEs will help improve models of those systems ahead of LISA’s anticipated launch in the mid-2030s.
“We’re going to keep observing Ansky for as long as we can,” Chakraborty said. “We’re still in the infancy of understanding QPEs. It’s such an exciting time because there’s so much to learn.”
NASA’s Mars rover Curiosity captured this image of its current workspace, containing well-preserved polygonal shaped fractures, with waffle or honeycomb patterns. The rover acquired this image using its Front Hazard Avoidance Camera (Front Hazcam) on May 1, 2025 — Sol 4527, or Martian day 4,527 of the Mars Science Laboratory mission — at 16:41:35 UTC.
NASA/JPL-Caltech
Written by Catherine O’Connell-Cooper, Planetary Geologist at University of New Brunswick
Earth planning date: Friday, May 2, 2025
From our Wednesday stopping spot, the drive direction ahead (looking along the path we would follow in the Wednesday drive) appeared to be full of rough, gnarly material, which can be tricky targets for contact science instruments like APXS. However, coming into planning this morning, we found a workspace with amazingly well preserved polygonal shaped fractures, with raised ridges (about 1 centimeter, or about 0.39 inches, high), looking like a patchwork of honeycombs, or maybe a patch of waffles. We have spotted these before but usually not as well preserved and extensive as this — we can see these stretching away into the distance for 20-30 meters (about 66-98 feet), almost to the edge of the “boxwork” fracture structures at “Ghost Mountain” butte in this Navcam image. We are all counting down the drives to get to the boxwork structures — this will be such an exciting campaign to be part of.
As APXS operations planner today, I was really interested to see if we could get APXS close to one of the raised ridges, to determine what they are made of. The Rover Planners were able to get a paired set of targets — “Orosco Ridge” along a ridge and “Box Canyon” in the adjacent, flat center of the polygon. The ChemCam team is also interested (in truth, everyone on the team is interested!!) in the composition of the ridges. So ChemCam will use LIBS to measure both bedrock and ridge fill at “Kitchen Creek” on the first sol of the plan and “Storm Canyon” on the second sol.
The “problem” with a workspace like this is picking which images to take in our short time here, before we drive on the second sol. We could stay here for a week and still find things to look at in this workspace. After much discussion, it was decided that MAHLI should focus on a “dog’s eye” mosaic (“Valley of the Moon”) along the vertical face of the large block. We hope this will allow us to examine how the fractures interact with each other, and with the preexisting layering in the bedrock.
Mastcam will then focus on the two main blocks in the workspace in an 8×4 (4 rows of 8 images) Kitchen Creek mosaic, which also encompasses the LIBS target of the same name, and a single image on the Storm Canyon LIBS target. Three smaller mosaics at “Green Valley Falls” (3×1), “Lost Palms Canyon” (7×2) and “San Andreas Fault” (1×2) will examine the relationships between the polygonal features and other fractures in the workspace, close to the rover.
Further afield, ChemCam will turn the “LD RMI” (Long-Distance Remote Micro Imager) on “Texoli” butte (the large butte to the side of the rover, visible in this image from sol 4528). Both Mastcam and ChemCam will image the boxwork fracture system near Ghost Mountain — they are so close now, it’s just a few drives away! Any information we get now may be able to help us answer some of the questions we have on the origin and timing of the boxwork structures, especially when we can combine it with the in situ analysis we will be getting shortly! (Did I mention how excited we all are about this campaign?)With all the excitement today on the wild fracture structures, it could be easy to overlook Curiosity’s dataset of environmental and atmospheric data. For more than 12 years now, we have been collecting information on dust and argon levels in the atmosphere, water and chlorine levels in the subsurface, wind speeds, humidity, temperature, ultraviolet radiation, pressure, and capturing movies and images of dust devils. This weekend is no different, adding a full complement of activities from almost every team — Navcam, REMS, DAN, Mastcam, ChemCam, and APXS will all collect data for the environmental and atmospheric theme group (ENV) in this plan.
Crew Kicks off Week with Agriculture and Tech Work, Wraps Spacewalk Cleanup
NASA astronaut and Expedition 72 Flight Engineer Anne McClain points a camera towards herself and takes a “space-selfie” during a spacewalk to upgrade the orbital outpost’s power generation system and relocate a communications antenna. Reflected in her helmet’s visor is fellow spacewalker and NASA astronaut Nichole Ayers.
NASA
The Expedition 73 crew members are kicking off a busy week aboard the International Space Station. Technology development, space botany, and clean up following last Thursday’s spacewalk topped Monday’s schedule.
The morning started with NASA astronaut Nichole Ayers and current station commander Takuya Onishi of JAXA (Japan Aerospace Exploration Agency) teaming up to check out the petri plates housing thale cress plant in the station’s Veggie facility. The duo harvested some of the plants as part of the APEX-12 experiment, which observes how space radiation affects plant genetics.
Following space botany work, Ayers moved onto troubleshooting communications and network hardware before completing her daily two hours of exercise on the station’s treadmill and Advanced Resistive Exercise Device.
To wrap up cleanup duties following Ayers’ and NASA Astronaut Anne McClain’s 5 hour and 44-minute spacewalk last Thursday, Onishi spent the afternoon on spacesuit work, performing a cooling loop scrub. He was later joined by NASA’s Jonny Kim as the first-time space resident removed batteries from the spacesuits and the propulsive jetpack system (SAFER).
Kim also spent part of his day connecting with students from Verona, Italy, where he answered questions about living and working aboard the orbiting laboratory during a Ham Radio call and later performed routine on-orbit plumbing.
McClain set her sights to monitoring an ongoing tech demonstration that looks at capabilities for producing pharmaceutical ingredients in space that could be used to synthesize medications during future deep-space missions. She removed samples in the ADSEP cassette carriers then installed new cassettes for future analysis. Midafternoon, she photographed tomato plants for a space agricultural study to help researchers better understand if crops can be cultivated in space without photosynthesis. She later collected water samples from the Water Processing Assembly for chemical analysis and reorganized cargo racks in SpaceX’s Dragon cargo spacecraft, which arrived to the microgravity lab April 22.
The station’s three cosmonauts had a busy day of cleaning, cargo operations, and experiment prep. Flight Engineers Sergey Ryzhikov and Alexey Zubritsky worked together auditing Roscosmos cargo that will be loaded in the Progress 90 spacecraft before its eventual departure from the station. The duo then installed photo and videography hardware for a future experiment that will examine the station’s aerodynamic force. Meanwhile, Flight Engineer Kirill Peskov conducted routine orbital cleaning in the Roscosmos segment and synced up the cameras the trio uses to photograph Earth and its landmarks.
Subsurface spherules: This image of the Hare Bay abrasion patch was acquired by the WATSON camera on Sol 1480 (April 19, 2025), showing dark-colored spherules set in a fine-grained light-toned matrix. These spherules appear to be smaller versions of similar structures that have been found in numerous rocks in the vicinity. Perseverance is currently working to collect a sample of these spherules to return to Earth. WATSON (Wide Angle Topographic Sensor for Operations and eNgineering) is a close-range color camera that works with the rover’s SHERLOC instrument (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals); both are located on the turret at the end of the rover’s robotic arm.
NASA/JPL-Caltech
Written by Denise Buckner, Postdoctoral Fellow at NASA’s Goddard Space Flight Center
Over the past few weeks, Perseverance has been investigating some curious spherules peppered across the “Witch Hazel Hill” region along the rim of Jezero crater. A striking cluster of the small bubble-shaped stones were first spotted by the Mastcam-Z instrument on Sol 1442 (March 11, 2025) at “Broom Point,” in a rock named “St. Pauls Bay.” A few sols later, a similar assemblage was discovered by the SuperCam instrument at the “Mattie Mitchell” outcrop near “Puncheon Rock.” As the rover continued along its traverse, spherules continued to appear. At the targets St. Pauls Bay and Mattie Mitchell, the spherules are densely packed and almost look like bunches of grapes. Elsewhere, similar smaller spherules were found intermixed with other grains within the rock. At a target called “Wreck Apple” at the “Sally’s Cove” outcrop, individual spherules were set in a matrix of coarse, dark grains. Even more of these circular features are embedded in finer-grained, layered bedrock at a nearby area called “Dennis Pond.”
Spherules at St. Pauls Bay: NASA’s Mars Perseverance rover acquired this image, a striking cluster of spherules, on March 11, 2025 – Sol 1442, or Martian day 1,442 of the Mars 2020 mission – at the local mean solar time of 11:12:40. Perseverance used its Left Mastcam-Z camera; Mastcam-Z is a pair of cameras located high on the rover’s mast.
NASA/JPL-Caltech/ASU
Spherules at Wreck Apple: NASA’s Mars Perseverance rover found smaller spherules in a coarse-grained matrix. The rover captured this image using the WATSON camera on March 27, 2025 – Sol 1458, or Martian day 1,458 of the Mars 2020 mission – at the local mean solar time of 15:36:04. WATSON (Wide Angle Topographic Sensor for Operations and eNgineering) is a close-range color camera located on the turret at the end of the rover’s robotic arm.
NASA/JPL-Caltech
Although the team was intrigued by the spherule-rich layers at Sally’s Cove and Dennis Pond, these outcrops were challenging for the rover arm to access. After some searching to find an accessible target, the team decided to perform an abrasion at a neighboring outcrop, called “Pine Pond,” which contained an extension of the Dennis Pond layers. The team picked the target “Hare Bay” in hopes of finding spherules within a rock interior, and conducting proximity science observations with PIXL and SHERLOC to investigate their composition and internal structure. Images of the abrasion patch taken by WATSON show that Hare Bay contains light-toned medium-sized grains, with millimeter-sized spherules dotted throughout the rock! Leading hypotheses for the origin of these spherules include formation by volcanic activity or impact-related processes.
Having found an accessible spherule-bearing rock, the team is currently hard at work collecting a spherule-filled sample! Combined with the information already gathered by Mastcam-Z, SuperCam, PIXL, SHERLOC, and WATSON, future laboratory analyses could help solve the mystery of when, where, and how these spherules formed, which can in turn detangle the geological events that formed and transformed the surface of Mars over billions of years!
