PARIS: Why is Mars barren and uninhabitable, while life has always thrived here on our relatively similar planet Earth? A discovery made by a Nasa rover has offered a clue for this mystery, new research said on Wednesday, suggesting that while rivers once sporadically flowed on Mars, it was doomed to mostly be a desert planet.
Mars is thought to currently have all the necessary ingredients for life except for perhaps the most important one: liquid water. However, the red surface is carved out by ancient rivers and lakes, showing that water once flowed on our nearest neighbour.
There are currently several rovers searching Mars for signs of life that could have existed back in those more habitable times, millions of years ago.
Earlier this year, Nasa’s Curiosity rover discovered a missing piece in this puzzle: rocks that are rich in carbonate minerals. These “carbonates” — such as limestone on Earth — act as a sponge for carbon dioxide, pulling it in from the atmosphere and trapping it in rock.
A new study, published in the journal Nature, modelled exactly how the existence of these rocks could change our understanding of Mars’s past.
Brief ‘oases’
Lead study author Edwin Kite, a planetary scientist at the University of Chicago and a member of the Curiosity team, said it appeared there were “blips of habitability in some times and places” on Mars. But these “oases” were the exception rather than the rule.
On Earth, carbon dioxide in the atmosphere warms the planet. Over long timescales, the carbon becomes trapped in rocks such as carbonates. Then, volcanic eruptions spew the gas back into the atmosphere, creating a well-balanced climate cycle supportive of consistently running water.
However, Mars has a “feeble” rate of volcanic outgassing compared to Earth, Kite said. This throws off the balance, leaving Mars much colder and less hospitable.
According to the modelling research, the brief periods of liquid water on Mars were followed by 100 million years of barren desert — a long time for anything to survive.
It is still possible that there are pockets of liquid water deep underground on Mars we have not yet found, Kite said. Nasa’s Perseverance Rover, which landed on an ancient Martian delta in 2021, has also found signs of carbonates at the edge of dried-up lake, he added. Next, the scientists hope to discover more evidence of carbonates.
Kite said the best proof would be returning rock samples from the Martian surface back to Earth — both the United States and China are racing to do this in the next decade.
Are we alone?
Ultimately, scientists are searching for an answer to one of the great questions: how common are planets like Earth that can harbour life? Astronomers have discovered nearly 6,000 planets beyond our Solar System since the early 1990s. But only for Mars and Earth can scientists study rocks which allow them to understand the planet’s past, Kite said.
If we do determine that Mars never hosted even tiny micro-organisms during its watery times, that would indicate it is difficult to kick-start life across the universe.
But if we discover proof of ancient life, that would “basically be telling us the origin of life is easy on a planetary scale,” Kite said.
A telescope operated by the University of Hawaiʻi has detected the third known interstellar (from outside our solar system) object to enter our solar system. Researchers say that it poses no danger to Earth.
Full ATLAS image and a cutout of the discovery image
The discovery was made by UH’s NASA-funded Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in Rio Hurtado, Chile. ATLAS is a global network of four telescopes managed by the UH Institute for Astronomy that scan the skies for asteroids that could pose a threat to Earth. According to researchers, the object is moving right through the Milky Way, making it difficult to distinguish amidst all the stars. But researchers say this is one of ATLAS’s strengths.
“Spotting a possible interstellar object is incredibly rare, and it’s exciting that our UH-operated system caught it,” said John Tonry, UH Institute for Astronomy astronomer and professor. “These interstellar visitors provide an extremely interesting glimpse of things from solar systems other than our own. Quite a few come through our inner solar system each year, although 3I/ATLAS is by far the biggest to date. The chances of one actually hitting the Earth are infinitesimal, less than 1 in 10 million each year, but ATLAS is continually searching the sky for any object that might pose a problem.”
Full discovery image
The newly identified object, designated A11pl3Z, was added to the International Astronomical Union’s Near-Earth Object confirmation list on July 1, and a Minor Planet Electronic Circular was just released that names it 3I/ATLAS. It is currently soaring toward the sun on a trajectory and with speed that reveals that it originated from outside our solar system, and will leave the solar system again after passing the Sun. Early estimates suggest the object may be as large as 12 miles in diameter. Researchers say it will make its closest approach to the sun—about twice the distance from Earth—in October, traveling at more than 150,000 miles per hour.
This diagram shows the trajectory of interstellar comet 3I/ATLAS as it passes through the solar system. It will make its closest approach to the Sun in October. (Image credit: NASA/JPL-Caltech)
Although 3I/ATLAS appears on the Near-Earth Object list, there is no risk of collision with Earth or even a close pass. It is sobering, however, that if it struck the Earth (and it will not) it would create an explosion more than 100 times greater than the asteroid that killed the dinosaurs. Researchers suspect that 3I/ATLAS is a comet and it should show increasing activity as it gets closer to the Sun, although it will never get warm enough to make a naked eye display.
The four-telescope ATLAS system is the first line of defense in surveying hazardous asteroids capable of monitoring the entire dark sky every 24 hours. Read this UH News story for more about ATLAS.
Visitor number 3?
This marks the third likely interstellar visitor, following the discoveries of ʻOumuamua in 2017 and comet 2I/Borisov in 2019. ʻOumuamua was first detected by UH’s Pan-STARRS1 telescope on Haleakalā and became the first object to receive an official interstellar designation. It caught global attention with its strange, elongated shape and unexpected acceleration as it exited the solar system. Although it showed no visible tail, its motion suggested comet-like behavior. Most scientists now agree that it was a natural object, likely a comet from another star system, although its exact nature is still debated.
SwRI, UTSA selected by NASA to test electrolyzer technology aboard parabolic flight
Research aims to address NASA’s technology shortfalls and support future missions to Moon, Mars Grant and Award Announcement
Southwest Research Institute SAN ANTONIO — July 1, 2025 —Southwest Research Institute (SwRI) and The University of Texas at San Antonio (UTSA) will receive a $500,000 award from NASA’s TechLeap Prize program to flight test novel electrolyzer technology designed to improve the production of propellants and life-support compounds on the Moon, Mars or near-Earth asteroids. The project, known as the Mars Atmospheric Reactor for Synthesis of Consumables (MARS-C), is led by SwRI’s Kevin Supak and Dr. Eugene Hoffman and UTSA’s Dr. Shrihari “Shri” Sankarasubramanian.
TechLeap prizes are designed to support future missions by advancing transformative solutions that address NASA’s technology shortfalls. The SwRI/UTSA group is one of nine winners funded to test their payloads on suborbital, hosted orbital or parabolic flights. The program aims to accelerate the technology testing timeline, allowing completion within a year of the award.
SwRI and UTSA will evaluate the performance of a patent-pending electrolyzer developed with NASA support by Sankarasubramanian, an assistant professor in UTSA’s Department of Biomedical and Chemical Engineering, and his team. The device applies a voltage across two electrodes to drive the electrochemical conversion of a simulated Martian brine and carbon dioxide into methane and other hydrocarbons. This technology is designed to use local resources on the Moon or Mars to produce fuel, oxygen and other life support compounds needed for long-term human habitation..
The work builds on previous research conducted by SwRI, which involved studying boiling processes under partial gravity aboard parabolic flights. Designed to understand how liquids might behave on lunar or Martian surfaces, the research demonstrated that partial gravity affects surface bubble dynamics, which can affect gas production rates.
Supak, said:
In a partial gravity environment, like the Moon or Mars, a reduced buoyancy effect on gas bubbles in an electrolyzer poses challenges that aren’t present on Earth,
“We lack an understanding about chemical processes that leverage bubble nucleation in low gravity, which is the gap we aim to fill.”
To address this, SwRI and UTSA will integrate the technology into an existing SwRI-built flight rig and test it aboard a parabolic flight, capitalizing on the Institute’s successful history testing technology in reduced gravity aircraft and suborbital spacecraft.
Sankarasubramanian, said:
We plan to acquire bubble nucleation and fluid motion videos in an operating electrolyzer during the parabolic flight,
“Understanding these processes can help us improve the overall efficiency and performance of these electrolyzers.”
After the flight rig is complete, SwRI will conduct ground tests before the parabolic flight to establish operating procedures and ensure a successful demonstration. The flight is currently planned for 2026.
Supak, said:
Humans have an intrinsic drive to push the boundaries of what’s possible.
“Exploring space catalyzes technological advancements that have far-reaching benefits in our daily lives — often unanticipated innovations arise as a direct result of overcoming the unique challenges of space exploration.Establishing permanent presences on other planetary bodies could pave the way for unprecedented scientific discoveries and technological breakthroughs.”
READ the latest news shaping the hydrogen market at Hydrogen Central
SwRI, UTSA selected by NASA to test electrolyzer technology aboard parabolic flight, source
Published in Nature Geoscience, the study, led by the University of Adelaide and University of Melbourne, found long periods of sea ice loss surrounding the ice shelves occurred in the six to 18 months prior to calving, as well as the collapse of the ‘landfast’ sea ice attached to the ice shelves only weeks prior to the calving events.
“Sea ice is retreating at an unprecedented rate all around Antarctica and our work suggests this will put further pressure on already thinned and weakened ice shelves,” said Professor Luke Bennetts, from the University of Melbourne.
“This could lead to more large-scale calving events, with profound implications for the future of global sea levels.”
The Antarctic Ice Sheet is the thick layer of ice that sits on top of Antarctica. It holds enough fresh water to raise current sea levels by more than 50 metres.
Ice shelves are floating platforms that form as glaciers flow off the Antarctic continent onto the ocean, whereas sea ice forms when the surface of the ocean freezes.
“Except for a relatively short period around summer, sea ice creates a protective barrier between the ice shelves and the potentially damaging swells of the Southern Ocean. Without this barrier, the swells can bend and flex pre-weakened ice shelves until they break,” Professor Bennetts said.
Previous research has shown that warming temperatures are causing more rapid melting and more frequent ‘calving’ of icebergs from some ice shelves.
“Increased melting and calving does not directly increase sea levels, as the ice shelves are already floating on the ocean, but it reduces the ability of the ice shelves to push back against the glacial flow into the ocean, which does raise sea levels,” Professor Bennetts said.
Nathan Teder, a PhD candidate at the University of Adelaide who led the study, said his team also developed a novel mathematical model to quantify the ice shelf flexing caused by the huge Southern Ocean swells.
“There is currently no observation system that allows for long-term recording of swell waves that pass through Antarctic sea ice to reach ice shelves, so mathematical modelling is an essential link in quantifying the connection between ice shelf stability and changes in local sea ice and ocean conditions,” said Mr Teder.
The research was funded by the Australian Antarctic Science Program and the Australian Research Council and collaborators included the University of Melbourne, the University of Adelaide, the Australian Bureau of Meteorology, the University of Tasmania, and the Australian Antarctic Division.
In 2014 and 2016, the Himawari-8 and -9 satellites were launched into orbit. Owned and operated by the Japan Meteorological Agency (JMA), these satellites monitor global weather patterns and atmospheric phenomena using their multispectral Advanced Himawari Imagers (AHIs). In a recent study, a team led by the University of Tokyo presented infrared images that capture changes in Venus’ atmosphere, revealing unseen temperature patterns in its cloud tops. The results show that meteorological satellites can complement observations of Venus’ atmosphere by robotic missions and ground-based telescopes.
The team was led by Gaku Nishiyama, a visiting postdoctoral researcher at the University of Tokyo and the Institute of Space Research at the German Aerospace Center (DLR). The Max Planck Institute for Extraterrestrial Physics (MPE), National Institute of Advanced Industrial Science and Technology, the University of Tokyo’s Institute of Astronomy, Graduate School of Frontier Sciences, the National Astronomical Observatory of Japan (NAOJ), Institute of Space and Astronautical Science (ISAS) at the Japan Aerospace Exploration Agency (JAXA), the European Space Research and Technology Centre (ESTEC), and multiple universities.
Scientists have studied Venus’ atmosphere for decades, hoping to learn more about the dynamics of the hottest planet in the Solar System. However, several mysteries are still unresolved, such as its thermal tides and planetary-scale waves. As Nishiyama and his colleagues indicated in their study, multi-band spectral monitoring of Venus’ atmosphere would shed light on these and related phenomena. This presents multiple challenges, however, and robotic probes sent to Venus in the past decade have been limited to either single-band imagery or short observation periods. As Nishiyama said in a UTokyo press release:
The atmosphere of Venus has been known to exhibit year-scale variations in reflectance and wind speed; however, no planetary mission has succeeded in continuous observation for longer than 10 years due to their mission lifetimes. Ground-based observations can also contribute to long-term monitoring, but their observations generally have limitations due to the Earth’s atmosphere and sunlight during the daytime.
Nishiyama and his colleagues believe meteorological satellites could fill this gap thanks to their extended lifetimes and capabilities. The Himawari satellites are scheduled to remain operational for more than a decade (until 2029). In addition, the AHI instruments provide multi-band infrared coverage of Earth’s atmosphere to obtain temperature information from different altitudes, which is essential to tracking and predicting weather patterns. Lastly, the geostationary satellites can obtain images of the turbulent atmosphere when they are aligned with Earth and Venus.
To demonstrate the potential of these missions, the team used data from the Himawari-8 and -9 satellites to map the temporal dynamics of Venus’ atmosphere and create a comparative analysis with previous datasets. This consisted of extracting all the AHI images where Venus was visible in the distance (437 images in total) to create a dataset. This allowed them to track temperature variations in multiple infrared bands in Venus’ cloud tops over time. This was then analyzed on daily and annual timescales to discern variability in Venus’ thermal tides and planetary-scale waves.
Their analysis confirmed that both the tides and waves are subject to changes in amplitude over time, which appear to decrease with altitude. Moreover, it allowed them to identify calibration discrepancies in data retrieved by previous planetary missions. Last, the results suggest that variations in thermal tide amplitude could be linked to variations in the structure of Venus’ atmosphere that occur every decade or so. However, the limited temporal resolution of the AHI data makes it very difficult to determine the physics behind these variations at this time.
Nevertheless, Nishiyama and his team believe their analysis method will provide vital data about Venus until future planetary missions are sent there. At present, there are six missions under development worldwide, including NASA’s Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy (VERITAS) orbiter and the Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging (DAVINCI) probe, and the ESA’s EnVision orbiter. In the meantime, Nishiyama and his colleagues are already contemplating how their research using multi-band spectral data from Earth observation satellites could be applied to the study of other planets:
I think that our novel approach in this study successfully opened a new avenue for long-term and multi-band monitoring of solar system bodies. This includes the moon and Mercury, which I also study at present. Their infrared spectra contain various information on physical and compositional properties of their surface, which are hints at how these rocky bodies have evolved until the present. We hope this study will enable us to assess physical and compositional properties, as well as atmospheric dynamics, and contribute to our further understanding of planetary evolution in general.
The paper that details their findings appeared in Earth, Planets and Space on June 30th.
July 2 (UPI) — The Australian aerospace firm Gilmour Space has again delayed the launch of its Eris 1 rocket, the country’s first orbital rocket.
Gilmour Space said Wednesday that it was standing down from a planned launch of what would be the first test flight of the rocket.
“We’ve made the tough call to postpone this week’s launch,” the company said in a statement. It said the pause would give them a longer and more flexible launch window, and the team “a chance to rest after an intense few weeks of testing and prep.”
The company said the new launch window would depend on weather conditions and approval from regulators but that the next launch window is likely no earlier than July 16.
On Monday, the company had said that the rocket was on the launch pad but that the winds weren’t favorable for a launch.
Gilmour Space had previously sought to launch the rocket on May 15 but encountered problems during routine shutdown procedures. At the time, the rocket’s payload fairing — a protective cone for the payload at the nose of the rocket — unexpectedly separated from the launch vehicle.
The cause of the incident went unexplained until May 30 when Gilmour Space revealed that the separation was caused by an unexpected power surge traced to electrical feedback during the vehicle’s shutdown sequence.
“No, it wasn’t a cockatoo,” the company said at the time.
The company was founded by brothers Adam and James Gilmour in 2015 and now has more than 200 employees.
The hot-Jupiter exoplanet HIP 67522b orbits its parent star, HIP 67522, so tightly that it appears to cause frequent flares from the star’s surface, heating and inflating the planet’s atmosphere, according an analysis of data from NASA’s Transiting Exoplanet Survey Satellite (TESS) and ESA’s CHaracterising ExoPlanets Telescope (CHEOPS).
An artist’s impression of the young planetary system HIP 67522. Image credit: J. Fohlmeister, AIP.
HIP 67522 is a G0-type star located about 417 light-years away in the constellation of Centaurus.
Otherwise known as HD 120411, 2MASS J13500627-4050090 and TYC 7794-2268-1, the star is a member of the Scorpius-Centaurus stellar association.
HIP 67522 is approximately 17 million years old, and hosts two young exoplanets.
The inner planet, HIP 67522b, orbits the star once every 7 days and is about 10 times the diameter of Earth, or close to that of Jupiter.
Using five years of data from NASA’s TESS and ESA’s CHEOPS telescopes, ASTRON astronomer Ekaterina Ilin and her colleagues took a closer look at the HIP 67522 system.
They found that the planet and its host star form a powerful but likely a destructive bond.
In a manner not yet fully understood, the planet hooks into the star’s magnetic field, triggering flares on the star’s surface; the flares whiplash energy back to the planet.
Combined with other high-energy radiation from the star, the flare-induced heating appears to have increased the already steep inflation of the planet’s atmosphere.
This might well mean that the planet won’t stay in the Jupiter size-range for long.
One effect of being continually pummeled with intense radiation could be a loss of atmosphere over time.
In another 100 million years, that could shrink the planet to the status of a hot Neptune, or, with a more radical loss of atmosphere, even a sub-Neptune, a planet type smaller than Neptune that is common in our Galaxy but lacking in our Solar System.
“We’ve found the first clear evidence of flaring star-planet interaction, where a planet triggers energetic eruptions on its host star,” said Dr. Ilin, first author of a paper published in the journal Nature.
“What’s particularly exciting is that this interaction has persisted for at least three years, allowing us to study it in detail.”
“This type of star-planet interaction has been expected for a long time, but getting the observational evidence was only possible with this large space telescope dataset,” said Dr. Katja Poppenhäger, an astronomer at the Leibniz-Institut für Astrophysik Potsdam and the Universität Potsdam.
“The planet is essentially subjecting itself to an intense bombardment of radiation and particles from these induced flares,” said Dr. Harish Vedantham, an astronomer at ASTRON.
“This self-inflicted space weather likely causes the planet’s atmosphere to puff up and may dramatically accelerate the rate at which the planet is losing its atmosphere.”
In an accompanying paper in the journal Astronomy & Astrophysics, the astronomers confirm that HIP 67522 is a magnetically active star with strong radio wave emission powered by its magnetic field.
They observed the star at low radio frequencies for about 135 hours with the Australian Telescope Compact Array (ATCA), revealing it as a bright and bursty source of radio waves.
At the same time, they found no signs of radio wave flares that could be attributed to the interaction of the star with the planet.
“The non-detection is compatible with expectations that the planet-induced flares are too faint to be detected by ATCA, in line with the Nature paper’s conclusion of magnetic star-planet interaction driving flaring activity,” they said.
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Ekaterina Ilin et al. Close-in planet induces flares on its host star. Nature, published online July 2, 2025; doi: 10.1038/s41586-025-09236-z
Ekaterina Ilin et al. 2025. Searching for planet-induced radio signal from the young close-in planet host star HIP 67522. A&A, in press; doi: 10.1051/0004-6361/202554684
NASA and its partners will discuss the upcoming crew rotation to the International Space Station during a pair of news conferences on Thursday, July 10, from the agency’s Johnson Space Center in Houston.
First is an overview news conference at 12 p.m. EDT with mission leadership discussing final launch and mission preparations on the agency’s YouTube channel.
Next, crew will participate in a news conference at 2 p.m. on NASA’s YouTube channel, followed by individual astronaut interviews at 3 p.m. This is the final media opportunity with Crew-11 before they travel to NASA’s Kennedy Space Center in Florida for launch.
The Crew-11 mission, targeted to launch in late July/early August, will carry NASA astronauts Zena Cardman and Mike Fincke, JAXA (Japan Aerospace Exploration Agency) astronaut Kimiya Yui, and Roscosmos cosmonaut Oleg Platonov to the orbiting laboratory. The crew will launch aboard a SpaceX Dragon spacecraft on the company’s Falcon 9 rocket from Launch Complex 39A.
United States-based media seeking to attend in person must contact the NASA Johnson newsroom no later than 5 p.m. on Monday, July 7, at 281-483-5111 or jsccommu@mail.nasa.gov. A copy of NASA’s media accreditation policy is available online.
Any media interested in participating in the news conferences by phone must contact the Johnson newsroom by 9:45 a.m. the day of the event. Media seeking virtual interviews with the crew must submit requests to the Johnson newsroom by 5 p.m. on Monday, July 7.
Briefing participants are as follows (all times Eastern and subject to change based on real-time operations):
12 p.m.: Mission Overview News Conference
Steve Stich, manager, Commercial Crew Program, NASA Kennedy
Bill Spetch, operations integration manager, International Space Station Program, NASA Johnson
NASA’s Space Operations Mission Directorate representative
Sarah Walker, director, Dragon Mission Management, SpaceX
Mayumi Matsuura, vice president and director general, Human Spaceflight Technology Directorate, JAXA
Crew-11 members available for a limited number of interviews
Selected as a NASA astronaut in 2017, Cardman will conduct her first spaceflight. The Williamsburg, Virginia, native holds a bachelor’s degree in Biology and a master’s in Marine Sciences from the University of North Carolina at Chapel Hill. At the time of selection, she was pursuing a doctorate in geosciences. Cardman’s geobiology and geochemical cycling research focused on subsurface environments, from caves to deep sea sediments. Since completing initial training, Cardman has supported real-time station operations and lunar surface exploration planning. Follow @zenanaut on X and @zenanaut on Instagram.
This will be Fincke’s fourth trip to the space station, having logged 382 days in space and nine spacewalks during Expedition 9 in 2004, Expedition 18 in 2008, and STS-134 in 2011, the final flight of space shuttle Endeavour. Throughout the past decade, Fincke has applied his expertise to NASA’s Commercial Crew Program, advancing the development and testing of the SpaceX Dragon spacecraft and Boeing Starliner spacecraft toward operational certification. The Emsworth, Pennsylvania, native is a graduate of the United States Air Force Test Pilot School and holds bachelors’ degrees from the Massachusetts Institute of Technology, Cambridge, in both aeronautics and astronautics, as well as Earth, atmospheric and planetary sciences. He also has a master’s degree in aeronautics and astronautics from Stanford University in California. Fincke is a retired U.S. Air Force colonel with more than 2,000 flight hours in over 30 different aircraft. Follow @AstroIronMike on X and Instagram.
With 142 days in space, this will be Yui’s second trip to the space station. After his selection as a JAXA astronaut in 2009, Yui flew as a flight engineer for Expedition 44/45 and became the first Japanese astronaut to capture JAXA’s H-II Transfer Vehicle using the station’s robotic arm. In addition to constructing a new experimental environment aboard Kibo, he conducted a total of 21 experiments for JAXA. In November 2016, Yui was assigned as chief of the JAXA Astronaut Group. He graduated from the School of Science and Engineering at the National Defense Academy of Japan in 1992. He later joined the Air Self-Defense Force at the Japan Defense Agency (currently the Ministry of Defense). In 2008, Yui joined the Air Staff Office at the Ministry of Defense as a lieutenant colonel. Follow @astro_kimiya on X.
The Crew-11 mission also will be Platonov’s first spaceflight. Before his selection as a cosmonaut in 2018, Platonov earned a degree in engineering from Krasnodar Air Force Academy in aircraft operations and air traffic management. He also earned a bachelor’s degree in state and municipal management in 2016 from the Far Eastern Federal University in Vladivostok, Russia. Assigned as a test cosmonaut in 2021, he has experience in piloting aircraft, zero gravity training, scuba diving, and wilderness survival.
‘This is the central region of the Bullet Cluster, which is made up of two massive galaxy clusters. The vast number of galaxies and foreground stars in the image were captured by NASA’s James Webb Space Telescope in near-infrared light. Glowing, hot X-rays captured by NASA’s Chandra X-ray Observatory appear in pink. The blue represents the dark matter, which was precisely mapped by researchers with Webb’s detailed imaging. Normally, gas, dust, stars, and dark matter are combined into galaxies, even when they are gravitationally bound within larger groups known as galaxy clusters. The Bullet Cluster is unusual in that the intracluster gas and dark matter are separated, offering further evidence in support of dark matter. (See the defined galaxy clusters within the dashed circle.’ | Credit: NASA, ESA, CSA, STScI, CXC; Science: James Jee (Yonsei University/UC Davis), Sangjun Cha (Yonsei University), Kyle Finner (IPAC at Caltech)
NASA’s James Webb Space Telescope (JWST) and Chandra X-ray Observatory combined their efforts to look at the Bullet Cluster in a new way, enabling scientists to precisely map the cluster’s dark matter.
Webb’s near-infrared imaging capabilities enabled astronomers to capture the highest detailed images yet of the Bullet Cluster, which comprises a pair of massive galaxy clusters. With Webb’s highly sensitive cameras, researchers can see fainter, more distant galaxies in the Bullet Cluster than ever before.
“With Webb’s observations, we carefully measured the mass of the Bullet Cluster with the largest lensing dataset to date, from the galaxy clusters’ cores all the way out to their outskirts,” says Sangjun Cha, the lead author on a new research paper published this week in The Astrophysical Journal Letters. Cha is a PhD student at Yonsei University in Seoul, South Korea.
“Webb’s images dramatically improve what we can measure in this scene — including pinpointing the position of invisible particles known as dark matter,” adds Kyle Finner, a co-author of the new research paper and an assistant scientist at IPAC at Caltech in Pasadena, California.
As NASA explains, “all galaxies are made up of stars, gas, dust, and dark matter, which are bound together by gravity.” The Bullet Cluster is not just a galaxy, but a grouping of two “very massive collections of galaxies.”
The galaxy clusters, which are massive and therefore have powerful gravitational forces, can act as gravitational lenses that significantly magnify the light of background galaxies. The amount of gravitational lensing, when compared against the amount of visible mass in a cluster, enables scientists to infer the distribution of invisible dark matter.
Bullet Cluster — NIRCam image
“Gravitational lensing allows us to infer the distribution of dark matter,” says co-author James Jee, professor at Yonsei University and research associate at UC Davis in California.
It is helpful to think about gravitational lensing and dark matter using a metaphor of a pond filled with crystal-clear water and pebbles, Jee says.
“You cannot see the water unless there is wind, which causes ripples,” the scientist explains. “Those ripples distort the shapes of the pebbles below, causing the water to act like a lens.” This same phenomenon occurs in space, where the water represents dark matter, and the pebbles in the example represent background galaxies.
With Webb’s imaging capabilities, it is much easier to see and measure the galaxies, including the background ones, meaning it is possible to weigh both visible and invisible matter (dark matter) in the galaxy clusters. The researchers also mapped and measured the collective light emitted by intracluster stars. These are stars that are no longer bound to an individual galaxy.
“We confirmed that the intracluster light can be a reliable tracer of dark matter, even in a highly dynamic environment like the Bullet Cluster,” Cha says. If intracluster stars are not bound to galaxies, and instead are bound to dark matter, scientists could learn much more about dark matter and its distribution.
Image credits: NASA, ESA, CSA, STScI, CXC; Science: James Jee (Yonsei University/UC Davis), Sangjun Cha (Yonsei University), Kyle Finner (IPAC at Caltech). Video credits: NASA, ESA, CSA, Joseph DePasquale (STScI)
In his new book ’52 Assignments: Night Photography’, award-winning astrophotographer Josh Dury invites you to raise your lens and embark on a journey through the night sky to capture everything from the moon and Milky Way, to satellite megaconstellations and aurora.
The latest book in Ammonite Press’ popular ’52 Assignments’ series seeks to demystify the technically demanding hobby of astrophotography by offering stargazers a year’s worth of weekly workshops packed with advice and photography techniques for capturing the night sky.
Each assignment will help aspiring astrophotographers gain a better understanding of how their camera performs at night, while arming them with the technical knowledge and tricks of the trade needed to capture spectacular images of the post-sunset realm.
Space.com caught up with Dury to discuss his experience of writing the book, how aspiring astrophotographers can benefit from the assignments, and the importance of capturing unique images of the night sky.
A composite image showing satellite trails criss-crossing the night sky. (Image credit: Josh Dury)
Josh Dury: The whole experience really started off from a very young age, when I was seven years old. Back then, there were children’s programs about the planet Mars, and it was when I purchased my first telescope that [I was] ultimately encouraged me to look up to life on other worlds, at the planets of the solar system. I thought, well, how can I document that?
So it began by taking images with these planetary cameras at the time. But then I pursued an education and then a degree in photography, and now pursuing a career as a landscape astrophotographer. It’s one of those bucket list things I’ve always wished to do to educate others, which is to publish a book. But at the same time, when I was approached by Ammonite Press, [there were] very pressing issues in the astrophotography community.
With the [rising] popularity of taking images of the night sky and the Milky Way, not only are we seeing environmental effects of light pollution and artificial light at night, but we’re also seeing consequences of [so many people] going to dark sky places — hundreds of photographers in one go producing artificial light in dark sky areas. And so this book aims to promote sustainable astrophotography so that we can take further respect and consideration for the night sky and also just the etiquette of being respectful of other photographers in these dark sky areas. I feel it’s a pressing issue at the moment that needs to be addressed.
Breaking space news, the latest updates on rocket launches, skywatching events and more!
You’re a passionate dark sky advocate, yet a number of the assignments that you picked out specifically take aim at light pollution and the satellites that crisscross our sky. Could you tell me a little bit more about your process, your thought process, and including them as targets in the book?
I think it’s very important to take images of light polluted areas, because it demonstrates the state of affairs in which we are living. The majority of the British public and further afield live under light polluted skies. When I was a youngster living on the Mendip Hills, I was one of the lucky ones [who got] to look up at the beautiful dark skies and see the Milky Way glowing on down, but also the pressing issues that have come from that.
“…are we potentially the last generation that will see the night’s sky in its entirety?”
As a delegate of Dark Sky International, I work with a group of like minded people who are producing research on the impacts of light pollution. So not only the effects to astronomers and astrophotographers like myself, but also wildlife conservation, how light at night is affecting nocturnal and marine wildlife as well as ourselves. Human health, how exposure to light at night affects chemical reactions during our sleeping patterns, our circadian rhythm and effectively affecting melatonin cycles. But [there’s] also the next pressing issue, which is satellite megaconstellations. I respect the fact that it’s very much a double edged sword.
We live in the 21st Century. We need internet technology, globally, across the world, for communication. But there’s also the pressing issue of what it’s doing to the night sky?
It is a concerning issue, and it’s going to grow. So it’s my concern as a delegate and an astrophotographer: are we potentially the last generation that will see the night sky in its entirety?
So including satellites as targets in the book was your way of grabbing people and making them look directly at the issue?
“You don’t need the latest photographic technologies to get a good image.”
Exactly, and even just after sundown, Anthony, when you look up, you will see them easily. You’ll just see one after another moving throughout the night. So when an avid or professional photographer takes an image of the sky, and they see one of the trails, they will easily — through the assignments — be able to identify what is a meteor and what is a satellite.
And I think it’s that readdressing issue of: ‘what is it we are looking at, what is it all about?’ I believe the connection between being an astronomer and an astrophotographer is to really know your subjects, because without that prior knowledge, things can easily be mistaken for [one another] in the night sky.
One of the assignments gives advice on how to capture a rare ‘planetary parade.’ (Image credit: Josh Dury)
Astrophotography is an inherently intimidating and technically demanding hobby, especially for beginners. That said, your book does a great job of demystifying the terms and camera settings needed to capture the night sky by breaking it down into individual projects, each of which adds to the user skill set and confidence over time. Could you walk us through your process when it came to creating the assignments?
Really it was putting myself back in my shoes when I was a youngster, but also the experience of being involved with astronomical societies, photographic societies, and years of research. Astrophotography is a technically competent area or niche within photography and so, as opposed to taking an image of, say, a sunset, or architecture, we’re dealing with much longer exposures. And also, we need to let as much light into our cameras as possible — identified as the aperture of our camera lenses — but we also have what’s called ISO (camera sensitivity) and so again, it’s just trying to break down these barriers. You don’t need the latest photographic technologies to get a good image.
I still take a lot of my images on a Sony α7S II, which is considered a more traditional model of the α7 series, but it’s still more than competent [enough] to take these quality images. One pressing issue, I would say, however, is the camera. You need a good quality piece of glass. In the past couple of years I’ve been lucky enough to work with Sigma as a leading purveyor for astrophotography style lenses, dealing with F numbers like f 1.4 that let the light into your camera. That’s where the cutting edge technology comes in, and quite frankly, breaking new boundaries to test this equipment and hopefully the ambition of making it more accessible to everyone.
The assignments tend to provide a structure for the shoot, and then you ask the photographer to go off and put their own personal touches on the composition. What were the challenges when it came to finding the line between handholding and simply providing the necessary structure for newcomers to enjoy the pastime?
“When a viewer or a potential client is looking on their mobile devices at hundreds of submissions all the time, they’re looking for images that are unique and not those same compositions.”
I have taken it upon myself to think deep within what is of interest to me, through my background, through ancient astronomy and stone circles and ancient sites. But I also appreciate that there have been purveyors in astrophotography who were there long before I was and have their own take on the astrophotography landscape. This is my concern when I see locations which have been photographed a hundred times or more, [how can you find] originality?
And so the book is there to speak to the reader, to dive deep into what interests them, and to [help them] apply that knowledge to produce an image that has never been seen before. So it could be one of your hobbies, it could be one of your interests, somewhere where you like walking, your own area of the landscape. Just something new, something refreshing.
When a viewer or a potential client is looking on their mobile devices at hundreds of submissions all the time, they’re looking for images that are unique and not those same compositions. And most importantly, it’s got [to have] an interesting story to tell. So I’ll give you one example, which is one of the assignments titled ‘Meteor Showers.’ So the image [I took as an example] was the Perseid meteors over Stonehenge. Yes, okay, it’s been photographed millions of times before, but it’s somewhere of interest to me. I thought ‘I’m trying out a particular lens here. I want to capture the Milky Way [tumbling] down’. Just being a creative mind, I can picture it in my mind already and [I] executed this image over three and a half hours. It was endorsed by NASA, Apollo 11 astronaut Buzz Aldrin and the European Space Agency. So to have this backing, even by a scientific journal, was huge and it just shows where originality goes a long way.
Perseid meteors captured streaking through the skies over Stonehenge in Wiltshire, UK. (Image credit: Josh Dury)
Do you have a personal favorite assignment that you keep coming back to?
I would say it would have to be one of the final assignments, which is traveling far afield. Not only have I been lucky enough to go to some of the darkest skies in the world, but also to make friendships through the experience. So that particular photograph [Assignment 51] captures the iconic Moai statues of Easter Island from the southern hemisphere skies, and the photograph wouldn’t be possible without the support of the local Islanders and the community. And this is again something which is very easily forgotten in astrophotography today, is that there are people who help you along the way.
Towards the end of the book, you get to the aspirational, bucket list shots that people eventually want to get. But it was really refreshing that throughout, for quite a few of the assignments all you needed was a camera and a tripod, there was no real barrier to entry. If you are already a photographer or have any interest in it, you’ve probably already got most of this gear and then you can just enjoy it and embrace it (and maybe pick up a star tracker).
“With astrophotography, it’s about having fun.”
Well, this is it. So you take yourself on that initial journey. So you start off with the basics, your tripod, your camera, and then as you begin to learn more about your camera and how it operates, is then the realization that if I want to take even cleaner, crisper images, that I will need to deploy the use of a star tracker.
And so it’s just trying to break down what this information means to an audience, and that with one of these devices, you can track the sky for a longer period of time, so that, yes, you can use the longer exposures, you can bring down the ISO levels and produce a cleaner image. But by that point, already, you’re learning. And this is the whole point of the book is to take you for a guided rhythm, really, of the assignments themselves.
A colorful aurora captured above a Norman church situated on the Knowlton Henge earthwork in Dorset, UK. (Image credit: Josh Dury)
So what do you think would be one of the most difficult photography concepts or techniques for a newcomer to pick up that’s included in your book?
There’s a number. So I would say, first of all, image stacking, which is addressed in the assignments. Why is there a need to stack images? So at night we have to remember that, as we have camera settings with a greater sensitivity [and] a longer exposure, when the camera has produced the image you’ll zoom in on it and it almost looks like the surface of sandpaper — it’s very textured. And so the purpose of stacking is so that computer software — Photoshop, being one of them — can read the individual images and, like a cake, stack them together. And so by doing that, it increases what’s known as the signal-to-noise ratio and produces a cleaner image as a result. And then you can produce those minor adjustments to make the Milky Way more representative of what you’ve seen on the night.
Is there anything else you’d like to say to our readers about the book?
“…by remaining true to yourself, you interact with your subjects more.”
With astrophotography, it’s about having fun. That is what I’ve learned throughout the experience. But also not to be put off by numbers and competition, that’s so easily done now, by social media, peer pressure, likes and the modern day following count, none of that at all. Do it for the reason you enjoy doing it and the love of the subject.
Final question — for someone who picks the book up this week to start their journey in astrophotography, what is the one piece of golden advice that you would give them to carry through their entire journey?
Remain true to yourself. It’s something I don’t see very often in astrophotography, but by remaining true to yourself, you interact with your subjects more. It becomes an emotional experience, and through that connection and understanding of a story, [you get] an image that has never been seen before, and ultimately to connect with our open window that is the universe.
This interview has been edited for length. You can buy ’52 Assignments: Night Photography’ at Amazon.com.
