All's not as it appears, this tale has many twists -
but if I wasn't here documenting the story
would that mean that the plot did not exist?

— Peter Hammill

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Trump Administration Moves to Severely Curtail Access to Gender-Affirming Care for Minors

Scientific American.com - Thu, 12/18/2025 - 11:20am

Health officials on Thursday announced a slew of measures that seek to restrict access to gender-affirming health care for young transgender people in the U.S.

Categories: Astronomy

Sitting by a window may improve blood sugar levels for type 2 diabetes

New Scientist Space - Space Headlines - Thu, 12/18/2025 - 11:00am
Our cells follow 24-hour circadian rhythms that regulate our blood sugar levels and are heavily influenced by light exposure. Scientists have harnessed this to show that just sitting by a window improves blood sugar control in people with type 2 diabetes
Categories: Astronomy

Sitting by a window may improve blood sugar levels for type 2 diabetes

New Scientist Space - Cosmology - Thu, 12/18/2025 - 11:00am
Our cells follow 24-hour circadian rhythms that regulate our blood sugar levels and are heavily influenced by light exposure. Scientists have harnessed this to show that just sitting by a window improves blood sugar control in people with type 2 diabetes
Categories: Astronomy

Using Bent Light to Map Complex Planetary Architectures

Universe Today - Thu, 12/18/2025 - 9:31am

With new technologies comes new discoveries. Or so Spider Man’s Uncle Ben might have said if he was an astronomer. Or a scientist more generally - but in astronomy that saying is more true than many other disciplines, as many discoveries are entirely dependent on the technology - the telescope, imager, or processing algorithm, used to collect data on them. A new piece of technology, the Nancy Grace Roman Space Telescope, is exciting scientists enough that they are even starting to predict what kind of discoveries it might make. One such type of discovery, described in a pre-print paper on arXiv by Vito Saggese of the Italian National Institute for Astrophysics and his co-authors on the Roman Galactic Exoplanet Survey Project Infrastructure Team, is the discovery of many more multiplantery exoplanet systems an astronomical phenomena Roman is well placed to detect - microlensing.

Categories: Astronomy

Satellites Used to Have Months to Avoid Collisions—Now They Have Days

Scientific American.com - Thu, 12/18/2025 - 9:00am

In the era of mega constellations, spacecraft typically have less than a week to avoid crashes

Categories: Astronomy

Two Möbius Strips Combine to Create a Bizarre Object That Only Exists in 4D

Scientific American.com - Thu, 12/18/2025 - 8:00am

In geometry, there are surfaces that do without an inside or outside—and some need at least four dimensions to exist

Categories: Astronomy

Igloos on Mars? How Future Astronauts Could Use Ice to Survive

Scientific American.com - Thu, 12/18/2025 - 7:00am

Humans traveling to Mars will need protective habitats to live on the harsh surface. Ice could help

Categories: Astronomy

10 Mind-Blowing Brain Discoveries from 2025

Scientific American.com - Thu, 12/18/2025 - 6:30am

From glowing neurons to newborn memories, here are the most fascinating brain discoveries of 2025

Categories: Astronomy

Hi ya! Hyha

NASA - Breaking News - Wed, 12/17/2025 - 7:25pm
Explore This Section

This image from NASA’s Mars Perseverance rover shows a potential megablock on the Jezero crater rim, taken by the Mastcam-Z instrument’s “right eye.” Mastcam-Z is a pair of cameras located high on the rover’s mast. Perseverance acquired this image looking east across the rim heading towards “Lac de Charmes” on Dec. 7, 2025 — Sol 1706, or Martian day 1,706 of the Mars 2020 mission — at the local mean solar time of 13:38:46. NASA/JPL-Caltech/ASU

Written by Margaret Deahn, Ph.D. student at Purdue University 

NASA’s Mars 2020 rover is currently trekking towards exciting new terrain. After roughly four months of climbing up and over the rim of Jezero crater, the rover is taking a charming tour of the plains just beyond the western crater rim, fittingly named “Lac de Charmes.” This area just beyond Jezero’s rim will be the prime place to search for pre-Jezero ancient bedrock and Jezero impactites — rocks produced or affected by the impact event that created Jezero crater.  

The formation of a complex crater like Jezero is, well… complex. Scientists who study impact craters like to split the formation process into three stages: contact & compression (when the impactor hits), excavation (when materials are thrown out of the crater), and modification (when gravity causes everything to collapse). This process happens incredibly fast, fracturing the impacted rock and even melting some of the target material. Sometimes on Earth, the classic “bowl” shaped crater has been completely weathered and unrecognizable, so geologists are able to identify craters by the remnants of their impactites. Just when you thought it couldn’t get any more complicated — Jezero crater’s rim is located on the rim of another, even bigger basin called Isidis. That means there is an opportunity to have impactites from both cratering events exposed in and just around the rim — some of which could be several billions of years old! We may have already encountered one of these blocks on our trek towards Lac de Charmes. In the foreground of this image taken by the Mastcam-Z instrument on the rover, there is a potential impactite called a “megablock” that the team has named “Hyha.” We can actually see this block from orbit, it is that large! The team is excited to continue exploring these ancient rocks as we take our next steps off Jezero’s rim.

Explore More

3 min read Curiosity Blog, Sols 4731-4742: Finishing Up at Nevado Sajama

Article


1 week ago

2 min read Curiosity Blog, Sols 4723-4730: Digging Into Nevado Sajama

Article


1 week ago

2 min read Curiosity Blog, Sols 4716-4722: Drilling Success at Nevado Sajama

Article


4 weeks ago

Keep Exploring Discover More Topics From NASA

All Mars Resources

Explore this collection of Mars images, videos, resources, PDFs, and toolkits. Discover valuable content designed to inform, educate, and inspire,…


Rover Basics

Each robotic explorer sent to the Red Planet has its own unique capabilities driven by science. Many attributes of a…


Mars Exploration: Science Goals

The key to understanding the past, present or future potential for life on Mars can be found in NASA’s four…


Mars Perseverance Rover

The Mars Perseverance rover is the first leg the Mars Sample Return Campaign’s interplanetary relay team. Its job is to…

Categories: NASA

Hi ya! Hyha

NASA News - Wed, 12/17/2025 - 7:25pm
Explore This Section

This image from NASA’s Mars Perseverance rover shows a potential megablock on the Jezero crater rim, taken by the Mastcam-Z instrument’s “right eye.” Mastcam-Z is a pair of cameras located high on the rover’s mast. Perseverance acquired this image looking east across the rim heading towards “Lac de Charmes” on Dec. 7, 2025 — Sol 1706, or Martian day 1,706 of the Mars 2020 mission — at the local mean solar time of 13:38:46. NASA/JPL-Caltech/ASU

Written by Margaret Deahn, Ph.D. student at Purdue University 

NASA’s Mars 2020 rover is currently trekking towards exciting new terrain. After roughly four months of climbing up and over the rim of Jezero crater, the rover is taking a charming tour of the plains just beyond the western crater rim, fittingly named “Lac de Charmes.” This area just beyond Jezero’s rim will be the prime place to search for pre-Jezero ancient bedrock and Jezero impactites — rocks produced or affected by the impact event that created Jezero crater.  

The formation of a complex crater like Jezero is, well… complex. Scientists who study impact craters like to split the formation process into three stages: contact & compression (when the impactor hits), excavation (when materials are thrown out of the crater), and modification (when gravity causes everything to collapse). This process happens incredibly fast, fracturing the impacted rock and even melting some of the target material. Sometimes on Earth, the classic “bowl” shaped crater has been completely weathered and unrecognizable, so geologists are able to identify craters by the remnants of their impactites. Just when you thought it couldn’t get any more complicated — Jezero crater’s rim is located on the rim of another, even bigger basin called Isidis. That means there is an opportunity to have impactites from both cratering events exposed in and just around the rim — some of which could be several billions of years old! We may have already encountered one of these blocks on our trek towards Lac de Charmes. In the foreground of this image taken by the Mastcam-Z instrument on the rover, there is a potential impactite called a “megablock” that the team has named “Hyha.” We can actually see this block from orbit, it is that large! The team is excited to continue exploring these ancient rocks as we take our next steps off Jezero’s rim.

Explore More

3 min read Curiosity Blog, Sols 4731-4742: Finishing Up at Nevado Sajama

Article


1 week ago

2 min read Curiosity Blog, Sols 4723-4730: Digging Into Nevado Sajama

Article


1 week ago

2 min read Curiosity Blog, Sols 4716-4722: Drilling Success at Nevado Sajama

Article


4 weeks ago

Keep Exploring Discover More Topics From NASA

All Mars Resources

Explore this collection of Mars images, videos, resources, PDFs, and toolkits. Discover valuable content designed to inform, educate, and inspire,…


Rover Basics

Each robotic explorer sent to the Red Planet has its own unique capabilities driven by science. Many attributes of a…


Mars Exploration: Science Goals

The key to understanding the past, present or future potential for life on Mars can be found in NASA’s four…


Mars Perseverance Rover

The Mars Perseverance rover is the first leg the Mars Sample Return Campaign’s interplanetary relay team. Its job is to…

Categories: NASA

Excerpt—The Great Shadow, by Susan Wise Bauer

Scientific American.com - Wed, 12/17/2025 - 4:45pm

In an exclusive excerpt of her new book The Great Shadow, historian Susan Wise Bauer explores how sickness is distinct from injury and has shaped the way we think about ourselves and our world

Categories: Astronomy

Galaxies in the River

APOD - Wed, 12/17/2025 - 4:00pm

Large galaxies grow by eating small ones.


Categories: Astronomy, NASA

Jared Isaacman Confirmed to Head NASA at Pivotal Moment for the Space Agency

Scientific American.com - Wed, 12/17/2025 - 3:30pm

Billionaire Jared Isaacman is taking the reins at NASA at a challenging time for the space agency, as it faces budget cuts and technical hurdles that could scuttle its most ambitious missions

Categories: Astronomy

Scientists Are Baffled by This Bizarre Lemon-Shaped Exoplanet

Scientific American.com - Wed, 12/17/2025 - 2:20pm

Astronomers using the James Webb Space Telescope have discovered a bizarre-looking exoplanet that defies explanation

Categories: Astronomy

New Views of Saturn’s Moon Titan and Jupiter’s Moon Europa Complicate Ocean Worlds Theory

Scientific American.com - Wed, 12/17/2025 - 2:00pm

Oceans hiding within the crusts of distant moons are tantalizing targets for scientists looking for life beyond Earth

Categories: Astronomy

NASA’s Perseverance Mars Rover Ready to Roll for Miles in Years Ahead

NASA - Breaking News - Wed, 12/17/2025 - 1:31pm
NASA’s Perseverance Mars rover captured this view of a location nicknamed “Mont Musard” on Sept. 8, 2025. Made up of three images, the panorama also captures another region, “Lac de Charmes,” where the rover’s team will be looking for more rock core samples to collect in the year ahead.NASA/JPL-Caltech/ASU/MSSS

After nearly five years on Mars, NASA’s Perseverance rover has traveled almost 25 miles (40 kilometers), and the mission team has been busy testing the rover’s durability and gathering new science findings on the way to a new region nicknamed “Lac de Charmes,” where it will be searching for rocks to sample in the coming year.

Like its predecessor Curiosity, which has been exploring a different region of Mars since 2012, Perseverance was made for the long haul. NASA’s Jet Propulsion Laboratory in Southern California, which built Perseverance and leads the mission, has continued testing the rover’s parts here on Earth to make sure the six-wheeled scientist will be strong for years to come. This past summer, JPL certified that the rotary actuators that turn the rover’s wheels can perform optimally for at least another 37 miles (60 kilometers); comparable brake testing is underway as well.

Over the past two years, engineers have extensively evaluated nearly all the vehicle’s subsystems in this way, concluding that they can operate until at least 2031.

NASA’s Perseverance used its navigation cameras to capture its record-breaking drive of 1,350.7 feet (411.7 meters) on June 19, 2025. The navcam images were combined with rover data and placed into a 3D virtual environment, resulting in this reconstruction with virtual frames inserted about every 4 inches (0.1 meters) of drive progress. Credit: NASA/JPL-Caltech

“These tests show the rover is in excellent shape,” said Perseverance’s deputy project manager, Steve Lee of JPL, who presented the results on Wednesday at the American Geophysical Union’s annual meeting, the largest gathering of planetary scientists in the United States. “All the systems are fully capable of supporting a very long-term mission to extensively explore this fascinating region of Mars.”

Perseverance has been driving through Mars’ Jezero Crater, the site of an ancient lake and river system, where it has been collecting scientifically compelling rock core samples. In fact, in September, the team announced that a sample from a rock nicknamed “Cheyava Falls” contains a potential fingerprint of past microbial life.

More efficient roving

In addition to a hefty suite of six science instruments, Perseverance packs more autonomous capabilities than past rovers. A paper published recently in IEEE Transactions on Field Robotics highlights an autonomous planning tool called Enhanced Autonomous Navigation, or ENav. The software looks up to 50 feet (15 meters) ahead for potential hazards, then chooses a path without obstacles and tells Perseverance’s wheels how to steer there.

Engineers at JPL meticulously plan each day of the rover’s activities on Mars. But once the rover starts driving, it’s on its own and sometimes has to react to unexpected obstacles in the terrain. Past rovers could do this to some degree, but not if these obstacles were clustered near each other. They also couldn’t react as far in advance, resulting in the vehicles driving slower while approaching sand pits, rocks, and ledges. In contrast, ENav’s algorithm evaluates each rover wheel independently against the elevation of terrain, trade-offs between different routes, and “keep-in” or “keep-out” areas marked by human operators for the path ahead.

“More than 90% of Perseverance’s journey has relied on autonomous driving, making it possible to quickly collect a diverse range of samples,” said JPL autonomy researcher Hiro Ono, a paper lead author. “As humans go to the Moon and even Mars in the future, long-range autonomous driving will become more critical to exploring these worlds.”

New science

A paper published Wednesday in Science details what Perseverance discovered in the “Margin Unit,” a geologic area at the margin, or inner edge, of Jezero Crater. The rover collected three samples from that region. Scientists think these samples may be particularly useful for showing how ancient rocks from Mars’ deep interior interacted with water and the atmosphere, helping create conditions supportive for life.

From September 2023 to November 2024, Perseverance ascended 1,312 feet (400 meters) of the Margin Unit, studying rocks along the way — especially those containing the mineral olivine. Scientists use minerals as timekeepers because crystals within them can record details about the precise moment and conditions in which they formed.

Jezero Crater and the surrounding area holds large reserves of olivine, which forms at high temperatures, typically deep within a planet, and offers a snapshot of what was going on in the planet’s interior. Scientists think the Margin Unit’s olivine was made in an intrusion, a process where magma pushes into underground layers and cools into igneous rock. In this case, erosion later exposed that rock to the surface, where it could interact with water from the crater’s ancient lake and carbon dioxide, which was abundant in the planet’s early atmosphere.

Those interactions form new minerals called carbonates, which can preserve signs of past life, along with clues as to how Mars’ atmosphere changed over time.

“This combination of olivine and carbonate was a major factor in the choice to land at Jezero Crater,” said the new paper’s lead author, Perseverance science team member Ken Williford of Blue Marble Space Institute of Science in Seattle. “These minerals are powerful recorders of planetary evolution and the potential for life.”

Together, the olivine and carbonates record the interplay between rock, water, and atmosphere inside the crater, including how each changed over time. The Margin Unit’s olivine appeared to have been altered by water at the base of the unit, where it would have been submerged. But the higher Perseverance went, the more the olivine bore textures associated with magma chambers, like crystallization, and fewer signs of water alteration.

As Perseverance leaves the Margin Unit behind for Lac de Charmes, the team will have the chance to collect new olivine-rich samples and compare the differences between the two areas.

More about Perseverance

Managed for NASA by Caltech, NASA’s Jet Propulsion Laboratory in Southern California built and manages operations of the Perseverance rover on behalf of the agency’s Science Mission Directorate as part of NASA’s Mars Exploration Program portfolio.

To learn more about Perseverance, visit:

https://science.nasa.gov/mission/mars-2020-perseverance

News Media Contacts

Andrew Good / DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433 / 818-393-9011
andrew.c.good@jpl.nasa.gov / agle@jpl.nasa.gov

Karen Fox / Molly Wasser
NASA Headquarters, Washington
240-285-5155 / 240-419-1732
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

2025-143

Explore More 6 min read NASA Study Suggests Saturn’s Moon Titan May Not Have Global Ocean Article 10 hours ago 6 min read NASA JPL Shakes Things Up Testing Future Commercial Lunar Spacecraft Article 1 day ago 3 min read One of NASA’s Key Cameras Orbiting Mars Takes 100,000th Image Article 1 day ago Keep Exploring Discover More Topics From NASA Mars 2020: Perseverance Rover

NASA’s Mars Perseverance rover seeks signs of ancient life and collects samples of rock and regolith for possible Earth return.

Mars Exploration

Mars is the only planet we know of inhabited entirely by robots. Learn more about the Mars Missions.

Planetary Science

NASA’s planetary science program explores the objects in our solar system to better understand its history and the distribution of…

Mars: Facts

Mars is one of the most explored bodies in our solar system, and it’s the only planet where we’ve sent…

Categories: NASA

NASA’s Perseverance Mars Rover Ready to Roll for Miles in Years Ahead

NASA News - Wed, 12/17/2025 - 1:31pm
NASA’s Perseverance Mars rover captured this view of a location nicknamed “Mont Musard” on Sept. 8, 2025. Made up of three images, the panorama also captures another region, “Lac de Charmes,” where the rover’s team will be looking for more rock core samples to collect in the year ahead.NASA/JPL-Caltech/ASU/MSSS

After nearly five years on Mars, NASA’s Perseverance rover has traveled almost 25 miles (40 kilometers), and the mission team has been busy testing the rover’s durability and gathering new science findings on the way to a new region nicknamed “Lac de Charmes,” where it will be searching for rocks to sample in the coming year.

Like its predecessor Curiosity, which has been exploring a different region of Mars since 2012, Perseverance was made for the long haul. NASA’s Jet Propulsion Laboratory in Southern California, which built Perseverance and leads the mission, has continued testing the rover’s parts here on Earth to make sure the six-wheeled scientist will be strong for years to come. This past summer, JPL certified that the rotary actuators that turn the rover’s wheels can perform optimally for at least another 37 miles (60 kilometers); comparable brake testing is underway as well.

Over the past two years, engineers have extensively evaluated nearly all the vehicle’s subsystems in this way, concluding that they can operate until at least 2031.

NASA’s Perseverance used its navigation cameras to capture its record-breaking drive of 1,350.7 feet (411.7 meters) on June 19, 2025. The navcam images were combined with rover data and placed into a 3D virtual environment, resulting in this reconstruction with virtual frames inserted about every 4 inches (0.1 meters) of drive progress. Credit: NASA/JPL-Caltech

“These tests show the rover is in excellent shape,” said Perseverance’s deputy project manager, Steve Lee of JPL, who presented the results on Wednesday at the American Geophysical Union’s annual meeting, the largest gathering of planetary scientists in the United States. “All the systems are fully capable of supporting a very long-term mission to extensively explore this fascinating region of Mars.”

Perseverance has been driving through Mars’ Jezero Crater, the site of an ancient lake and river system, where it has been collecting scientifically compelling rock core samples. In fact, in September, the team announced that a sample from a rock nicknamed “Cheyava Falls” contains a potential fingerprint of past microbial life.

More efficient roving

In addition to a hefty suite of six science instruments, Perseverance packs more autonomous capabilities than past rovers. A paper published recently in IEEE Transactions on Field Robotics highlights an autonomous planning tool called Enhanced Autonomous Navigation, or ENav. The software looks up to 50 feet (15 meters) ahead for potential hazards, then chooses a path without obstacles and tells Perseverance’s wheels how to steer there.

Engineers at JPL meticulously plan each day of the rover’s activities on Mars. But once the rover starts driving, it’s on its own and sometimes has to react to unexpected obstacles in the terrain. Past rovers could do this to some degree, but not if these obstacles were clustered near each other. They also couldn’t react as far in advance, resulting in the vehicles driving slower while approaching sand pits, rocks, and ledges. In contrast, ENav’s algorithm evaluates each rover wheel independently against the elevation of terrain, trade-offs between different routes, and “keep-in” or “keep-out” areas marked by human operators for the path ahead.

“More than 90% of Perseverance’s journey has relied on autonomous driving, making it possible to quickly collect a diverse range of samples,” said JPL autonomy researcher Hiro Ono, a paper lead author. “As humans go to the Moon and even Mars in the future, long-range autonomous driving will become more critical to exploring these worlds.”

New science

A paper published Wednesday in Science details what Perseverance discovered in the “Margin Unit,” a geologic area at the margin, or inner edge, of Jezero Crater. The rover collected three samples from that region. Scientists think these samples may be particularly useful for showing how ancient rocks from Mars’ deep interior interacted with water and the atmosphere, helping create conditions supportive for life.

From September 2023 to November 2024, Perseverance ascended 1,312 feet (400 meters) of the Margin Unit, studying rocks along the way — especially those containing the mineral olivine. Scientists use minerals as timekeepers because crystals within them can record details about the precise moment and conditions in which they formed.

Jezero Crater and the surrounding area holds large reserves of olivine, which forms at high temperatures, typically deep within a planet, and offers a snapshot of what was going on in the planet’s interior. Scientists think the Margin Unit’s olivine was made in an intrusion, a process where magma pushes into underground layers and cools into igneous rock. In this case, erosion later exposed that rock to the surface, where it could interact with water from the crater’s ancient lake and carbon dioxide, which was abundant in the planet’s early atmosphere.

Those interactions form new minerals called carbonates, which can preserve signs of past life, along with clues as to how Mars’ atmosphere changed over time.

“This combination of olivine and carbonate was a major factor in the choice to land at Jezero Crater,” said the new paper’s lead author, Perseverance science team member Ken Williford of Blue Marble Space Institute of Science in Seattle. “These minerals are powerful recorders of planetary evolution and the potential for life.”

Together, the olivine and carbonates record the interplay between rock, water, and atmosphere inside the crater, including how each changed over time. The Margin Unit’s olivine appeared to have been altered by water at the base of the unit, where it would have been submerged. But the higher Perseverance went, the more the olivine bore textures associated with magma chambers, like crystallization, and fewer signs of water alteration.

As Perseverance leaves the Margin Unit behind for Lac de Charmes, the team will have the chance to collect new olivine-rich samples and compare the differences between the two areas.

More about Perseverance

Managed for NASA by Caltech, NASA’s Jet Propulsion Laboratory in Southern California built and manages operations of the Perseverance rover on behalf of the agency’s Science Mission Directorate as part of NASA’s Mars Exploration Program portfolio.

To learn more about Perseverance, visit:

https://science.nasa.gov/mission/mars-2020-perseverance

News Media Contacts

Andrew Good / DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433 / 818-393-9011
andrew.c.good@jpl.nasa.gov / agle@jpl.nasa.gov

Karen Fox / Molly Wasser
NASA Headquarters, Washington
240-285-5155 / 240-419-1732
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

2025-143

Explore More 6 min read NASA Study Suggests Saturn’s Moon Titan May Not Have Global Ocean Article 13 hours ago 6 min read NASA JPL Shakes Things Up Testing Future Commercial Lunar Spacecraft Article 1 day ago 3 min read One of NASA’s Key Cameras Orbiting Mars Takes 100,000th Image Article 2 days ago Keep Exploring Discover More Topics From NASA Mars 2020: Perseverance Rover

NASA’s Mars Perseverance rover seeks signs of ancient life and collects samples of rock and regolith for possible Earth return.

Mars Exploration

Mars is the only planet we know of inhabited entirely by robots. Learn more about the Mars Missions.

Planetary Science

NASA’s planetary science program explores the objects in our solar system to better understand its history and the distribution of…

Mars: Facts

Mars is one of the most explored bodies in our solar system, and it’s the only planet where we’ve sent…

Categories: NASA

New Radar Data Chills Prospects of a Subglacial Lake on Mars

Sky & Telescope Magazine - Wed, 12/17/2025 - 1:01pm

There could be liquid water trapped under the southern polar cap of Mars. But new observations suggest otherwise.

The post New Radar Data Chills Prospects of a Subglacial Lake on Mars appeared first on Sky & Telescope.

Categories: Astronomy

Massive Stars Make Their Mark in Hubble Image

NASA Image of the Day - Wed, 12/17/2025 - 12:43pm
This NASA/ESA Hubble Space Telescope image features the blue dwarf galaxy Markarian 178 (Mrk 178) against a backdrop of distant galaxies in all shapes and sizes. Some of these distant galaxies even shine through the diffuse edges of Mrk 178.
Categories: Astronomy, NASA

Massive Stars Make Their Mark in Hubble Image

NASA - Breaking News - Wed, 12/17/2025 - 12:29pm
This NASA/ESA Hubble Space Telescope image features the blue dwarf galaxy Markarian 178 (Mrk 178) against a backdrop of distant galaxies in all shapes and sizes. Some of these distant galaxies even shine through the diffuse edges of Mrk 178.ESA/Hubble & NASA, F. Annibali, S. Hong

This NASA/ESA Hubble Space Telescope image features a glittering blue dwarf galaxy called Markarian 178 (Mrk 178). The galaxy, which is substantially smaller than our own Milky Way, lies 13 million light-years away in the constellation Ursa Major (the Great Bear).

Mrk 178 is one of more than 1,500 Markarian galaxies. These galaxies get their name from the Armenian astrophysicist Benjamin Markarian, who compiled a list of galaxies that were surprisingly bright in ultraviolet light.

While the bulk of the galaxy is blue due to an abundance of young, hot stars with little dust shrouding them, Mrk 178 gets a red hue from a collection of rare massive Wolf–Rayet stars. These stars are concentrated in the brightest, reddish region near the galaxy’s edge. Wolf–Rayet stars cast off their atmospheres through powerful winds, and the bright emission lines from their hot stellar winds are etched upon the galaxy’s spectrum. Both ionized hydrogen and oxygen lines are particularly strong and appear as a red color in this photo.

Massive stars enter the Wolf–Rayet phase of their evolution just before they collapse into black holes or neutron stars. Because Wolf–Rayet stars last for only a few million years, researchers know that something must have triggered a recent burst of star formation in Mrk 178. At first glance, it’s not clear what could be the cause — Mrk 178 doesn’t seem to have any close galactic neighbors that may have stirred up its gas to form new stars. Instead, researchers suspect that a gas cloud crashed into Mrk 178, or that the intergalactic medium disturbed its gas as the galaxy moved through space. Either disturbance could light up this tiny galaxy with a ripple of bright new stars.

Image credit: ESA/Hubble & NASA, F. Annibali, S. Hong

Categories: NASA