Tag: science

Webb spots aftermath of collision of two galaxies

10:06 am

colliding galaxies
Click for source.

Using the Webb Space Telescope, astronomers have discovered the collision of two spiral galaxies that appears to have caused a supermassive black hole to collapse in its wake.

The Webb false-color infrared image to the right shows the two galaxies as the red dots, both surrounded by a ring, with the supermassive black hole the bluish spot in between but offset somewhat to the left. Follow-up radio observations suggested that this bluish spot was a supermassive black hole, having a mass of a million suns and sucking up matter from the giant gas cloud that surrounds it.

The team proposes that the black hole formed there via the direct collapse of a gas cloud – a process that may explain some of the incredibly massive black holes Webb has found in the early universe.

This hypothesis however has enormous uncertainties, and requires a lot more observations to confirm. The black hole could simply exist unrelated to the galaxy collision, having come there from elsewhere. Or it could be from a third galaxy in this group that these initial observations have not yet detected.

The image however is quite cool.

0 comments

A distant globular cluster

10:03 am

A distant globular cluster
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a research project to study globular clusters in galaxies other than the Milky Way.

The data for this image comes from an observing programme comparing old globular clusters in nearby dwarf galaxies — the LMC [Large Magellanic Cloud], the Small Magellanic Cloud and the Fornax dwarf spheroidal galaxy — to the globular clusters in the Milky Way galaxy. Our galaxy contains over 150 of these old, spherical collections of tightly-bound stars, which have been studied in depth — especially with Hubble Space Telescope images like this one, which show them in previously-unattainable detail. Being very stable and long-lived, they act as galactic time capsules, preserving stars from the earliest stages of a galaxy’s formation.

Astronomers once thought that the stars in a globular cluster all formed together at about the same time, but study of the old globular clusters in our galaxy has uncovered multiple populations of stars with different ages. In order to use globular clusters as historical markers, we must understand how they form and where these stars of varying ages come from. This observing programme examined old globular clusters like NGC 1786 [pictured] in these external galaxies to see if they, too, contain multiple populations of stars. This research can tell us more not only about how the LMC was originally formed, but the Milky Way Galaxy, too.

This cluster, discovered in 1835 by John Herschel, is about 160,000 light years away.

2 comments

LIGO detects gravitational waves of largest black hole merger yet

9:22 am

The LIGO gravitational wave detector, spread across several continents, successfully detected the largest black hole merger yet on November 23, 2023.

The two black holes that merged were approximately 100 and 140 times the mass of the Sun. In addition to their high masses they are also rapidly spinning, making this a uniquely challenging signal to interpret and suggesting the possibility of a complex formation history. “This is the most massive black hole binary we’ve observed through gravitational waves, and it presents a real challenge to our understanding of black hole formation,” says Professor Mark Hannam, from Cardiff University and a member of the LIGO Scientific Collaboration. “Black holes this massive are forbidden through standard stellar evolution models. One possibility is that the two black holes in this binary formed through earlier mergers of smaller black holes.”

To date, approximately 300 black-hole mergers have been observed through gravitational waves, including candidates identified in the ongoing O4 run. Until now the most massive confirmed black-hole binary was the source of GW190521, with a much smaller total mass of “only” 140 times that of the sun.

As noted by the press release as well as this news article, present theories of stellar evolution say that these black holes could not have come from single stars, which are predicted to never be this massive. It is posited that each black hole might have formed from earlier mergers, but there is also a lot of uncertainty in the data. To quote the release again: “Extracting accurate information from the signal required the use of theoretical models that account for the complex dynamics of highly spinning black holes.”

That this detection was almost two years ago and only announced now makes me wonder if the timing of the announcement has more to do with lobbying and less to do with science. Trump’s proposed budget eliminates the U.S. funding portion for this project, and it is standard operating procedure for such projects to suddenly announce big discoveries timed to correspond to when Congress is considering the budget.

1 comment

Weird drainages on Mars

11:58 am

Weird drainages on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on Februay 11, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The camera team posted it yesterday as their own cool image, labeling it “A Fissure and Channel near Pavonis Mons”. From the caption:

A linear trough strikes northeast, then abruptly ends (or changes into a narrow ridge). Where the trough ends, a sinuous channel has an east-southeast strike, trending at almost a right angle to the trough. What happened to form these features?

We can speculate that first there was a southwest-to-northeast trending fracture or fault, perhaps associated with a volcanic vent. Groundwater (or some other runny fluid) coursed through the fault until overflowing and forming the sinuous channel. Continued movement through the fault carved a trough up to the overflow point.

The arrows indicate the downhill grades. Though this caption mentions groundwater, it is far more likely that the “runny fluid” was lava, as shown by the overview map below.
» Read more

1 comment

New census of inverted channels on Mars strongly suggests the planet once had more water

9:00 am

Martian ridges that imitate rivers
Click for original image.

A new review of inverted channels on Mars now strongly suggests that the red planet was once far wetter than presently seen, with the channels implying the existence of liquid rivers.

The discovery of more than 15,000 kilometres of ancient riverbeds on Mars suggests that the Red Planet may once have been much wetter than previously thought. Researchers looked at fluvial sinuous ridges, also known as inverted channels, across Noachis Terra – a region in Mars’ southern highlands. These are believed to have formed when sediment deposited by rivers hardened and was later exposed as the surrounding material eroded.

Similar ridges have been found across a range of terrains on Mars. Their presence suggests that flowing water was once widespread in this region of Mars, with precipitation being the most likely source of this water.

The image to the right is a good example of an inverted channel, a previous cool image posted in April 2025. It is located not in Noachis Terra but in the northern lowland plains.

The researchers argue that these channels suggest that about 3.7 billion years ago there were flowing liquid rivers on Mars, fed by precipitation. This conclusion however still does not explain how this could happen on a planet that is too cold with too thin an atmosphere for liquid water to exist. Every model so far proposed to make Mars warmer with a thicker atmosphere in the distant past remains questionable with many holes.

Could the inverted channels have been created by glacial activity, ice instead of liquid water? At present we don’t know enough about the Mars environment and the physics of such things in the planet’s one-third gravity to answer that question. It is however a question that scientists I think should be asking, based on the extensive evidence of glacial activity in the Martian mid-latitudes.

The big takeaway from this study however is that it adds weight to the overall trend seen in the data, that over time the total amount of water on the planet has declined. We can see this in glaciers, for example, with later glacial flows always falling short of previous flows. This research shows that even in the dry tropics there was once ample water, even if we don’t yet know what form it took.

0 comments

Sightseeing near Starship’s candidate Martian landing sites

2:21 pm

An interesting mesa near Starship's Martian landing zone
Click for original image.

Today’s cool image takes us sightseeing in the region on Mars that SpaceX has chosen for its prime landing zone for its Starship spaceship. The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 29, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a 465-foot-high unusually shaped mesa in this region.

The full resolution inset at the bottom of the picture focuses at the strange tilted layers on the southern slope of this mesa. Apparently the layers at this spot were pushed sideways so they lie significantly angled to the horizontal. Though it isn’t clear from this picture, it is possible that the mesa itself is made up of similar tilted layers, hidden below the surface. We can see the tilt only on the mesa’s southern flank because erosion has apparently exposed it.

Note also the black stain that surrounds the mesa. Though this might be caused by wind distributing dust, such stains have also been seen at a location where scientists suspect an inactive hot spring might exist, as well as another location where there may have been relatively recent volcanic activity.

Is this stain caused by any of these processes? In situ exploration would probably be necessary to find out. And we may soon actually have spaceships landing here in the relatively near future with the capability to do this.
» Read more

1 comment

Returning to Mars’ glacier country

3:21 pm

Overview map

Returning to Mars' glacier country
Click for original image.

Today’s cool image illustrates again why I rail against those who still claim Mars is dry. The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 2, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The picture was labeled simply as a “terrain sample” by the MRO camera team, which almost always signifies that it was taken not as part of any specific science research project or by request by a scientist, but to fill a gap in the camera’s schedule in order to maintain its proper temperature. When such a gap-filler picture is required, the team tries to pick interesting features in that time frame, but don’t always succeed.

In this case, that time frame placed MRO over the northern mid-latitudes and a region I label “glacier country” because practically every picture taken in this region shows glacial features. This picture is no exception. The white dot in the overview map above marks the location, in the Protonilus Mensae area of the 2,000-mile-long strip of glaciers. The arrow in the picture itself shows the downward grade of the glacial flow. The small 2,000-foot-wide crater appears as if the impact occurred on soft ice, and the stippled terrain surrounding it appears to resemble the feature geologists have labeled “brain terrain”, a surface feature unique to Mars and associated with near surface ice, though its exact formation process is not yet understood.

Nor have I cherry-picked this image to prove my point. Its glacial-like features are very typical for this region of Mars. Note for example the inset with the larger crater to the northeast. It appears almost buried by this glacial material, which has poured through the gap in its southwest quadrant to fill it. A close look at all the low lying terrain shows similar glacial-like flows.

Mars is surely not a paradise. It is bone-chillingly cold almost all the time. Its atmosphere is so thin and lacking in oxygen you would quickly suffocate if you tried to breath it. But the data continues to suggest that the red planet has ample supplies of near-surface ice outside of its dry tropics. All future colonists will need to do is dig a bit and process the water out.

1 comment

Astronomers link fast X-ray bursts with gamma ray bursts and supernovae

1:17 pm

Using observations of a fast X-ray burst (FXT) 2.8 billion light years away by a plethora of space- and ground-based telescopes, astronomers now think the burst was caused by a massive star’s supernova explosion that would normally result in a gamma ray burst (GRB), but does not because the star’s outer layers trap the gamma rays from escaping.

Through analysis of EP 250108a’s rapidly evolving signal over the first six days following initial detection, the team found that this FXT is likely a ‘failed’ variation of a gamma-ray burst (GRB). GRBs are the most powerful explosions in the Universe and have been observed preceding supernovae. During these events, violent geysers of high-energy particles burst through a star’s outer layers as it collapses in on itself. These jets flow at nearly the speed of light and are detectable by their gamma-ray emission.

EP 250108a appears similar to a jet-driven explosion, but one in which the jets do not break through the outer layers of the dying star and instead remain trapped inside. As the stifled jets interact with the star’s outer layers, they decelerate and their kinetic energy is converted to the X-rays detected by Einstein Probe.

As always, there are many uncertainties with this conclusion.

2 comments

EPA employees who publicly signed letter opposing Trump’s agenda have now been put on leave

1:42 pm

Trump defiant after being shot
Trump in charge

They apparently forgot who the American people elected and who is thus the boss! The 170 EPA employees who publicly signed a letter this week announcing their opposition to Trump’s policies at EPA have now all been put on leave, with the expectation that they will eventually lose their jobs as well.

Staffers at the Environmental Protection Agency who signed a letter of dissent against President Donald Trump have been placed on leave, reports The Hill. “The Environmental Protection Agency has a zero-tolerance policy for career bureaucrats unlawfully undermining, sabotaging, and undercutting the administration’s agenda as voted for by the great people of this country last November,” EPA spokeswoman Brigit Hirsch said in a written statement.

The letter, posted on June 30, 2025, made it very clear in its opening paragraph that these employees were willing to defy orders and sabotage the Trump administration.
» Read more

19 comments

Mars is not dry!

11:11 am

Global map of glaciers found on Mars

I once again feel compelled to rant against the shallow ignorance of too many people in both the journalism field as well as academia about the most recent data we now have of Mars. Two articles today once again show this ignorance, assuming blandly that Mars is a dry planet with little water on it anywhere, when orbital data over the past decade has unequivocally shown that — except for its equatorial regions — the planet is covered with a LOT of near-surface ice.

The headlines make this ignorance quite clear:

In both cases, the articles assume that the data obtained from rovers and landers in the dry Martian tropics applies to the entire planet. It does not. This evidence of a dry planet carries a bias that comes from the decision by the planetary community as well as NASA to send every rover to that dry equatorial region. Only one lander, Phoenix, has ever been successfully dropped far from the Martian equator, and it was purposely sent to a very high latitude, where it proved there was ice present just below the surface.

Orbital data in the past decade from both Mars Reconnaissance Orbiter and Mars Express has clearly shown that there is a lot of near surface ice on Mars, as shown by the map above. In the mid-latitudes the terrain is dominated by glaciers, as this is the region where the vast ice sheets in the high latitudes begin to fade away.

Only the equatorial region, indicated by the white lines on the map, is dry and barren. And yet, even here, orbital data has detected evidence that suggests underground ice still exists.

It seems to me that journalists and academic PR departments should know these facts, and include them in any reports about the dry nature of Mars’ equatorial regions.

13 comments

New data: the ozone hole occurs mostly because of the sunspot cycle and cosmic rays, not CFC pollution

1:18 pm

The ozone hole linked to the solar cycle

The uncertainty of science: A science paper released yesterday suggests that the ozone hole over Antarctica that scientists have been tracking for almost a half century is caused mostly by the solar cycle and the accompanying fluctuations in cosmic rays hitting the upper atmosphere, not the release of chlorofluorocarbons (CFCs) that used to be used in aerosol spray cans.

The graph to the right, from figure 2 of the paper, illustrates the data. The red line is the ozone hole fluctuations predicted by the paper’s model, labeled “CRE Theory”, based on the increase of cosmic ray radiation during solar minimum. The blue, black, and green lines indicate the actual fluctuations of ozone and temperature in the lower stratosphere where the ozone layer exists. As you can see, the model and actual fluctuations match quite closely. From the paper’s abstract:
» Read more

18 comments

Sunspot update: Sunspot activity rebounds somewhat in June

12:13 pm

As I have done since I started this website fifteen years ago, I post at the start of every month an update of the Sun’s ongoing sunspot activity, using the update that NOAA posts each month to its own graph of sunspot activity but annotated by me with extra information to illustrate the larger scientific context.

Below is that graph, showing that in June sunspot activity rebounded upward somewhat from the shocking drop in activity that occurred in May.

» Read more

0 comments

Another interstellar object identified entering the solar system

11:44 am

A11pl3Z's path through the solar system

Astronomers think they have identified another interstellar object that is now entering the solar system.

The dim space rock is currently at about magnitude 18.8. Our new visitor, A11pl3Z, will get its closest to the sun – at about 2 astronomical units (AU), or twice as far as Earth is from the sun – in October. As it reaches perihelion – its closest point to the sun – it should be moving at about 68 km/s relative to the sun, or at about 152,000 miles per hour.

The object’s calculated path through the solar system, shown by the blue line in the graphic to the right, as well as the object’s high speed, are why the astronomers think it is interstellar in origin. Both facts suggest it is coming from beyond the Oort cloud.

This is the third such object discovered, after Oumuamua (whose nature remains somewhat unknown), followed by Comet 21/Borisov.

UPDATE: The object has now been renamed 3I/Atlas. The “3I” indicates it is the third interstellar object discovered, and “Atlas” refers to the discovering telescope survey.

12 comments

Astronomers discover supernovae that apparently exploded twice

10:55 am

Double detonation supernova
Click for original picture.

Using the ground-based Very Large Telescope (VLT) in Chile, astronomers have discovered evidence suggesting a star apparently exploded twice went it went supernova several hundred years ago.

They detected this possibility by looking at the remnant of that blast, shown to the right. It shows a double halo, indicated by the blue and orange colors. The blue however is seen in both shells. As noted by the VLT’s press notice:

Calcium is shown in blue, and it is arranged in two concentric shells. These two layers indicate that the now-dead star exploded with a double-detonation.

This type of supernova, dubbed type 1a, occurs when a white dwarf sucks matter from its closely orbiting stellar companion. That material piles up on the surface of the star until it reaches critical mass and explodes, causing the supernova.

The two shells, suggesting a double detonation, fits a theory proposed for this process. From the paper’s abstract:

Our analysis reveals that the outer calcium shell originates from the helium detonation at the base of the outer envelope, while the inner shell is associated with the carbon–oxygen core detonation. This morphological distribution of intermediate-mass elements agrees qualitatively with the predicted signature of the double detonation of a sub-Chandrasekhar-mass white dwarf from a hydrodynamical explosion simulation.

In other words, the outer shell resulted from the explosion caused by the helium ripped from the companion star, with the resulting shockwave detonating the second explosion inside the white dwarf’s core.

That’s the theory at least. This data supports it, but it certainly doesn’t prove it.

1 comment

Methane climate satellite fails

10:07 am

Fifteen months into a five year mission it appears the methane climate satellite MethaneSat has apparently failed prematurely.

From the press release by the environmental activist organization Environmental Defense Fund that operated the satellite:

On Friday, June 20, the MethaneSAT mission operations lost contact with MethaneSAT. After pursuing all options to restore communications, we learned this morning that the satellite has lost power, and that it is likely not recoverable.

The satellite was unusual in that it was developed and built by this activist organization, not a government or academic institution. Its failure is especially unfortunate at this time, because this non-governmental approach to science research is exactly what the science community needs to pursue faced as it is with major cuts in federal funding.

9 comments

Webb detects unexpected “little red dots” in the early universe

11:52 am

The uncertainty of science: Using the Webb Space Telescope astronomers have begun to compile a small catalog of what they call “little red dots” [LRDs], objects in the very early universe that are very small, too small to be galaxies and are thus a mystery.

A team of astronomers recently compiled one of the largest samples of LRDs to date, nearly all of which existed during the first 1.5 billion years after the big bang. They found that a large fraction of the LRDs in their sample showed signs of containing growing supermassive black holes.

“We’re confounded by this new population of objects that Webb has found. We don’t see analogs of them at lower redshifts, which is why we haven’t seen them prior to Webb,” said Dale Kocevski of Colby College in Waterville, Maine, and lead author of the study. “There’s a substantial amount of work being done to try to determine the nature of these little red dots and whether their light is dominated by accreting black holes.”

The present most popular theory to explain the dots, based on the available data, is that the dots are newly formed black holes, their red light caused by material falling into the hole at millions of miles per hour. That theory has of course problems. For example, it doesn’t explain why we don’t see these dots in more recent times. Nor does it explain why the dots are dim in X-rays, a radiation expected from accreting black holes.

As always, the press release claims that this discovery does not “break” the present cosmological theories for the formation of the universe, but at the same time, it does illustrate our overall lack of knowledge about that early universe. We really don’t know very much, which means any theories we have are likely wrong simply due to our present ignorance.

3 comments

China releases images of Earth and Moon, taken by its Tianwen-2 asteroid probe

9:40 am

Tianwen-2 images of the Earth and the Moon
For original images go here and here.

According to a report today in China’s state-run press, its Tianwen-2 asteroid sample return spacecraft is operating normally, and has successfully taken pictures of both the Earth and the Moon to test its instrumentation.

Those images are to the right, cropped, reduced, and sharpened to post here.

The CNSA [China National Space Administration] said that the narrow-field-of-view navigation sensor equipped on the probe recently captured the images of Earth and the moon, demonstrating good functional performance.

The images released include a photograph of Earth obtained by Tianwen-2 when it was approximately 590,000 kilometers away from the planet, as well as a new photograph of the moon captured when it was about the same distance from the moon. After the images were transmitted back to the ground, they were processed and produced by scientific researchers.

The Tianwen-2 probe has currently been in orbit for over 33 days, at a distance from Earth exceeding 12 million kilometers, and it is in good working condition, the CNSA said.

The probe will take about a year to reach asteroid Kamo’oalewa, where it will fly in formation studying it for another year, during which time it will attempt to grab samples by two methods. One method is a copy of the touch-and-go technique used by OSIRIS-REx on Bennu. The second method, dubbed “anchor and attach,” is untried, and involves using four robot arms, each with their own drill.

3 comments

NASA still hoping to save its Lunar Trailblazer mission

8:59 am

Though the odds of success are very dim, NASA has decided to give engineers another few weeks to try to activate its Lunar Trailblazer orbiter, that stopped communicating with Earth the day after it was launched in late February.

NASA has extended recovery efforts of its Lunar Trailblazer spacecraft from mid-June to early July. Updated modeling of the spacecraft’s trajectory by the mission team indicates lighting conditions will continue to be favorable and may provide enough sunlight for the spacecraft’s solar panels to recharge its batteries to an operational state and turn on its radio.

…Should enough sunlight reach Lunar Trailblazer’s solar panels, the batteries may charge to a level that allows the spacecraft’s radio system to boot up. But as Lunar Trailblazer travels farther away, it will soon be too distant to recover because its telecommunications signals to Earth will be too weak for the mission to receive telemetry and command.

The mission team has determined that if they can regain command of the spacecraft, the propulsion system isn’t frozen, and the instruments remain operable, the spacecraft may be able to achieve an elliptical lunar orbit and complete its lunar science objectives.

As I said, the chance of success are not good.

1 comment

Baby stars illuminating the dust that surrounds them

10:03 am

Baby stars illuminating dark dust
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope showing the wispy bluish clouds made of dark dust that we can only see because the dust is illuminated by the reflected light from the five red and blue stars nearby. Think of the Moon, lit only by the reflected light of the Sun.

The photo however was not taken to study the clouds, but these baby stars, located in one of the closest star forming regions of the Milky Way.

GN 04.32.8 is a small part of the stellar nursery known as the Taurus Molecular Cloud. At only roughly 480 light-years from Earth in the constellation Taurus, it’s one of the best locations for studying newly forming stars. This reflection nebula is illuminated by the system of three bright stars in the centre of this image, mainly the variable star V1025 Tauri in the very centre. One of those stars overlaps with part of the nebula: this is another variable star that is named HP Tauri, but is classified as a T Tauri star, for its similarity to yet another variable star elsewhere in the Taurus Molecular Complex. T Tauri stars are very active, chaotic stars at an early stage of their evolution, so it’s no surprise that they appear in a prolific stellar nursery like this one! The three stars are also named HP Tau, HP Tau G2 and HP Tau G3; they’re believed to be gravitationally bound to each other, forming a triple system.

Eagle-eyed viewers might notice the small, squashed, orange spot, just left of centre below the clouds of the nebula, that’s crossed by a dark line. This is a newly-formed protostar, hidden in a protoplanetary disc that obstructs some of its light. Because the disc is edge-on to us, it’s an ideal candidate for study. Astronomers are using Hubble here to examine it closely, seeking to learn about the kinds of exoplanets that might be formed in discs like it.

As beautiful as this image is, it is that tiny protostar near the bottom that likely attracts the most interest from astronomers.

3 comments
1 … 19 20 21 22 23 … 439