Tag: exploration

The first preliminary research into landing a Mars helicopter in the Starship landing zone

12:58 pm

Map of rotorcraft images in Starship landing zone

In early November 2025 I posted a cool image from Mars Reconnaissance Orbiter (MRO) that had the very provocative label “Characterize Possible Rotorcraft Landing Site”. While this was not the first such image taken by scientists using MRO to scout out potential landing zones for future Mars helicopter missions (see here and here), this particular image was one of several taken recently that were all within the candidate landing zone for SpaceX’s Starship spacecraft, focused specifically on the low Erebus mountain chain that sits within this part of Mars’ northern lowland plains.

In the January image download from MRO, I found another such image, taken on December 1, 2025. The map to the right shows that Starship candidate landing zone, with all the images taken for SpaceX indicated. The inset adds all the recent images taken for this “possible rotorcraft” mission, including the December image and the previous four (here, here, here, and here), with orange representing images already obtained and yellow those requested but pending.

I decided I needed to find out more, and tracked down the scientist who had requested the images, Eldar Dobrea of the Planetary Science Institute in Arizona. In response to my email, he explained:
» Read more

5 comments

Icy Mars

2:26 pm

Overview map

Icy Mars

Today’s cool image once again illustrates the fact that most of Mars Mars is not a dry desert like the Sahara, as most news sources and the general public still believes, but a cold icy place similar to Antarctica, with plenty of near surface ice covering almost the whole planet, except for the dry equatorial regions (the one region we have sent almost all our landers and rovers).

The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on November 26, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows one small section of the floor of an unnamed very old and eroded 82-mile-wide crater located in the northern mid-latitudes of Mars.

That location is indicated by the white dot on the overview map above. This part of the mid-latitudes is a region I dub “glacier country”, a 2,000-mile long strip where practically every image taken there shows very obvious glacial features.

Today’s image is no different. The 2-mile-wide crater in the upper left appears blobby, as if the impact had landed in mud. Its interior is filled with what the scientists believe is glacial debris. The surrounding landscape has a similar appearance, as if the ground was slushy and easily misshapen by seasonal temperature changes. To the southwest of the crater, within what appears to be a surrounding splash apron, there appears to be an eroded drainage channel, likely created by the flow of glacial ice downward.

So, when you read articles telling you Mars is dry and scientists are still hunting for water there, know that whomever wrote that article had no idea what he or she were talking about. The scientists studying Mars know that Mars has lots of water. Except for the tropics below 30 degrees latitude, there is near surface ice everywhere. Their questions revolve instead on figuring out how deep and extensive it is, and how it has shaped Mars’ overall geology.

One comment

Second Escapade Mars orbiter completes a delayed engine burn

10:03 am

Engineers have now successfully placed both Escapade Mars orbiters in their parking orbit, the second orbiter completed the required engine burn after it was delayed due to unexpected telemetry during an earlier mid-course correction burn.

That unexpected telemetry suggested the engine was firing at a lower thrust than expected. Today’s update did not provide any additional information as to how the thrust issue had been solved or overcome. All it said was that both spacecraft will fire their engines in November 2026 as planned to head to Mars.

Leave a comment

Rubin Observatory’s first observations detects more than 2,000 asteroids

11:04 am

The first look patch, in which 2,103 asteroids were detected
The first look patch, in which 2,103 asteroids
were detected. Figure 1 of the paper.

Scientists have now published the first results from the Rubin Observatory in Chile during its on-going commissioning phase, during which they detected more than 2,000 asteroids in just one patch in the sky, most of which had been unknown previously and many rotating at record-breaking speeds.

You can read the paper here [pdf]. From the press release:

The study presents 76 asteroids with reliable rotation periods. This includes 16 super-fast rotators with rotation periods between roughly 13 minutes and 2.2 hours, and three ultra-fast rotators that complete a full spin in less than five minutes.

All 19 newly identified fast-rotators are longer than the length of an American football field (100 yards or about 90 meters). The fastest-spinning main-belt asteroid identified, named 2025 MN45, is 710 meters (0.4 miles) in diameter and it completes a full rotation every 1.88 minutes. This combination makes it the fastest-spinning asteroid with a diameter over 500 meters that astronomers have found.

All but one of these fast-rotators are in the main asteroid belt, with the exception a near-Earth asteroid.

This work essentially completes Rubin’s commissioning. It will begin full observations in 2026. From the paper:

Toward the start of 2026, the observatory will begin conducting the Legacy Survey of Space and Time (LSST), a decade-long campaign to repeatedly image the southern sky in multiple bands. The main LSST survey will use six filters spanning near-ultraviolet to near-infrared wavelengths, revisiting the same pointing twice each night, returning to take additional pairs every few nights. … The cadence is designed to result in a dataset capable of answering numerous and varied science cases, from understanding the nature of dark energy to discovering and characterizing millions of asteroids, comets, interstellar objects, and transneptunian objects (TNOs) in the solar system.

In building Rubin the astronomers have always thought their biggest problem was archiving and accessing this large dataset, and much work was spent developing a usable and accessible archive system. Even so, it will take thousands of scientists many decades to mine the discoveries that will be hidden there.

6 comments

Study: If Europa has an underground ocean, it is lifeless and dormant

9:43 am

Scientists analyzing the conditions that are believed to exist in Europa’s theorized underground ocean have concluded there is little geological activity within that ocean, reducing significantly the chances there is life there.

A new study led by Paul Byrne, an associate professor of earth, environmental and planetary sciences, at Washington University in St. Louis, throws cold water on the idea that Europa could support life at the seafloor. Using calculations that consider the moon’s size, the makeup of its rocky core and the gravitational forces from Jupiter, Byrne and a team of scientists conclude that Europa likely lacks the tectonic motion, warm hydrothermal vents or any other sort of underwater geologic activity that would presumably be a prerequisite for life.

“If we could explore that ocean with a remote-control submarine, we predict we wouldn’t see any new fractures, active volcanoes or plumes of hot water on the seafloor,” Byrne said. “Geologically, there’s not a lot happening down there. Everything would be quiet.” And on an icy world like Europa, a quiet seafloor might well mean a lifeless ocean, he added.

You can read the paper here [pdf]. It admits in its conclusion that these results have a lot of uncertainty, and the Europa Clipper mission, set to arrive in orbit around Jupiter in 2031, will reduce that uncertainty but not eliminate it, adding that “Ultimately, however, the true test of our results here will require directly accessing the ocean and, perhaps one day, the ocean floor itself.”

9 comments

Computer model: A thin ice cap can preserve liquid water on Mars

10:37 am

The parameters used in the computer model
Figure 1 of the paper, showing the parameters
used in the computer model

Using a computer model, scientists have found that a thin cap of ice can act to allow liquid water to exist in lakes on Mars, for extended periods of time.

You can read their paper here. From the abstract:

Working at a localized scale, we combine climate input from the Mars Weather Research & Forecasting general circulation model with geologic constraints from Curiosity rover observations to identify potential climatic conditions required to maintain a seasonally ice-free lake. Our results show that an initially small lake system (10 m deep) with ∼50 mm monthly water input and seasonal ice cover would retain seasonal liquid water for over 100 years, demonstrating conditions close to long-term lake survivability.

From the press release:

In some simulations, the lakes completely froze during colder seasons, whereas in others, the lakes remained liquid and were covered by a thin layer of ice instead of freezing solid. This thin ice acted as an insulating lid, significantly reducing water loss while still allowing sunlight to warm the lake ice during warmer months. As a result of this seasonal cycling, some simulated lakes barely changed in depth over decades, suggesting that they could be stable for longer durations even with average air temperatures below freezing for much of the time.

Because this research is based on computer modeling, it carries great uncertainties. At the same time, it seems to explain the puzzling nature of Martian geology, which has repeatedly suggested the existence of liquid water in the past on a planet that has always been too cold with too thin an atmosphere for liquid water to exist. Data has also suggested that pockets of liquid water might have existed at the base of glaciers. This research aligns with that data.

9 comments

Detection of the wake of Betelgeuse’s companion star

4:27 pm

The wake of Betelgeuse's companion star

Astronomers believe they have detected evidence of the wake created by Betelgeuse’s companion star as it plows through the primary star’s vast atmosphere.

You can read their paper here [pdf]. The cartoon to the right, annotated by me to post here, is figure 5 of the paper, looking down at Betelgeuse’s pole. It is not to scale. The scientists have nicknamed the companion Siwarha.

The team detected Siwarha’s wake by carefully tracking changes in the star’s light over nearly eight years. These changes show the effects of the previously unconfirmed companion as it plows through the outer atmosphere of Betelgeuse. This discovery resolves one of the biggest mysteries about the giant star, helping scientists to explain how it behaves and evolves while opening new doors to understanding other massive stars nearing the end of their lives.

Located roughly 650 light-years away from Earth in the constellation Orion, Betelgeuse is a red supergiant star so large that more than 400 million Suns could fit inside. Because of its enormous size and proximity, Betelgeuse is one of the few stars whose surface and surrounding atmosphere can be directly observed by astronomers, making it an important and accessible laboratory for studying how giant stars age, lose mass, and eventually explode as supernovae.

Using NASA’s Hubble and ground-based telescopes at the Fred Lawrence Whipple Observatory and Roque de Los Muchachos Observatory, the team was able to see a pattern of changes in Betelgeuse, which provided clear evidence of a long-suspected companion star and its impact on the red supergiant’s outer atmosphere. Those include changes in the star’s spectrum, or the specific colors of light given off by different elements, and the speed and direction of gases in the outer atmosphere due to a trail of denser material, or wake. This trail appears just after the companion crosses in front of Betelgeuse every six years, or about 2,100 days, confirming theoretical models.

Betelgeuse is essentially a giant blob that undulates like a blob of water floating in weightlessness on ISS. Knowing the location and orbit of this companion will help astronomers better understand the central star’s periodic inexplicable changes.

4 comments

“Round Deposits” in Martian crater

11:41 am

Round deposits in a crater
Click for original image.

Today’s cool image could also be entered into my “What the heck?!” category of strange Martian geology. The picture to the right, cropped, reduced, and sharpened to post here, was taken on October 19, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this as “Round Deposits in Crater.” And yup, that’s what we have, round and flat small mesas inside an unnamed 3,500-foot-wide very shallow crater (no more than 10-20 feet deep) that also appears to be sitting higher than the surrounding landscape. Furthermore, several nearby craters are also raised, with one having its own oblong flat interior mesa. Moreover, the terrain around the crater appears stippled, as if it has been eroding or sublimating away.

The latitude, 37 degrees north, provides the first clue for explaining this weird landscape.
» Read more

Leave a comment

Many Martian mysteries in one spot

11:29 am

Many Martian mysteries in one spot
Click for original image.

Just because there are no new images coming back from Mars at this time because the Sun is in the way does not mean we can’t enjoy more cool Martian images. The picture to the right, cropped, reduced, and sharpened to post here, was taken on October 20, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

Labeled merely a “terrain sample,” this means it was taken not as part of any particular research project but to fill a gap in the camera’s schedule. The camera team needs to take regular photographs in order to maintain the camera’s proper temperature, and when there is a long gap they add a terrain sample image to the schedule. Usually they try to pick some target of interest.

In this case the target is this 2,500-foot-high cliff, in which we can see a whole range of Martian geological mysteries. First there are the slope streaks on the cliff, a feature unique to Mars but as yet unexplained. Resembling avalanches, these streaks leave no debris piles at their base, do not change the topography in any way, and can appear randomly throughout the year, fading with time. Though the streaks in this picture are dark, streaks can also be bright.

Both the parallel ridges at the base of the cliff, as well as the cliff itself, are remnants of other major geological events, at least based on present theories.
» Read more

5 comments

The headwaters of an ancient Martian channel

11:46 am

glacial debris in canyon floor
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on October 24, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this simply as “irregular terrain.” It is far more than that. We are looking at a three-mile-wide shallow canyon, with what appear to be eroding glacial features on the canyon floor.

The location is at 35 degrees north latitude, so finding glacial features here is entirely unsurprising, especially because this location is the southern edge of the 2,000-mile-long mid-latitude strip in Mar’ northern hemisphere I label glacier country, because almost every picture shows such glacial features.

In this case, the channel also suggests a much more complex geological history, that could involve flowing water though flowing glaciers are increasingly becoming an alternative explanation.
» Read more

Leave a comment

Layers in the biggest canyon in the solar system

12:07 pm

Overview map

Layers in the solar system's biggest canyon
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on October 24, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The white dot on the overview map above marks the location, on the lower slopes of the south rim of Valles Marineris, the largest canyon on Mars and by far the largest so far discovered in the solar system. From the rim to the floor the elevation drop here is about 23,000 feet, with the layers shown in the picture to be about 5,000 feet above the canyon floor.

Those layers cover about 500 feet of that elevation drop. Each layer suggests a past event, possibly volcanic eruptions. The curved headwall near the upper left also suggests that some layers were avalanches or mass wasting events flowing downhill to the northeast, one on top of another.

As always, the scale of Valles Marineris is hard to imagine. The rim is 20 miles to the south, but the canyon’s opposite rim is from 140 to 300 miles to the north. You could fit two to five Grand Canyons in this part of Valles Marineris and each would look small in comparison.

One comment

Hubble images gigantic protoplanetary disk

10:20 am

Largest known protoplanetary disk
Click for original image.

Cool image time! The picture to the right, rotated, cropped, and reduced to post here, was taken by the Hubble Space Telescope on February 8, 2025, and shows what scientists believe is the largest protoplanetary disk so far measured.

Located roughly 1,000 light-years from Earth, IRAS 23077+6707, nicknamed “Dracula’s Chivito,” spans nearly 400 billion miles — 40 times the diameter of our solar system to the outer edge of the Kuiper Belt of cometary bodies. The disk obscures the young star within it, which scientists believe may be either a hot, massive star, or a pair of stars. And the enormous disk is not only the largest known planet-forming disk; it’s also shaping up to be one of the most unusual.

…The impressive height of these features wasn’t the only thing that captured the attention of scientists. The new images revealed that vertically imposing filament-like features appear on just one side of the disk, while the other side appears to have a sharp edge and no visible filaments. This peculiar, lopsided structure suggests that dynamic processes, like the recent infall of dust and gas, or interactions with its surroundings, are shaping the disk.

You can read the peer-reviewed paper here [pdf]. The structure of this system has left them with more questions than answers. They can’t see the central star due to the dust. They don’t know if any planets exist as yet in the system. They don’t really understand the structural details that they can see.

One comment

Two very different galaxies

9:54 am

Two very different galaxies.
Click for original.

Cool image time! The picture to the right, reduced and sharpened to post here, was released today as the Hubble picture of the week. From the caption:

The trick is that these galaxies are not actually very close. The large blue galaxy MCG-02-05-050 is located 65 million light-years from Earth; its brighter smaller companion MCG-02-05-050a, at 675 million light-years away, is over ten times the distance! Owing to this, MCG-02-05-050a is likely the larger galaxy of the two, and MCG-02-05-050 comparatively small. Their pairing in this image is simply an unlikely visual coincidence.

The smaller blue galaxy, also called Arp 4, has an active nucleus that emits a lot of energy, suggesting the presence of a supermassive black hole. Less is known about the more distant orange galaxy.

Leave a comment

Curiosity’s exploration of boxwork on Mount Sharp

11:55 am

Curiosity panorama, December 18, 2025
Click for high resolution panorama. For original images, go here, here, and here.

Overview map
Click for interactive map.

Cool image time! The panorama above was created from three photographs taken on December 18, 2025 (here, here, and here) by the right navigation camera on the Mars rover Curiosity.

The view is north, looking down the flanks of Mount Sharp and across the floor of Gale Crater to its rim about 20 to 30 miles away. In comparing this view with a similar one taken in July, it is obvious that the Martian atmosphere has become far dustier during the last six months. The rim and the mountains beyond are hardly visible now through the haze.

The blue dot on the overview map to the right marks Curiosity’s present position. The yellow lines indicate roughly the area covered by this panorama. The while dotted line indicates the rover’s travels, while the red dotted line its planned routes.

As you can see by both the rover’s tracks in the panorama above and the white dotted line in the overview, Curiosity has been traversing back and forth across the boxwork formation of criss-crossing ridges for more than half a year, as the science team attempts to decipher what caused these ridges and hollows. They have also done some drilling in this effort.

The science team has been getting close to the day it will move on, resuming Curiosity’s climb of Mount Sharp, but they keep finding things amidst this boxwork that requires additional study. For example, consider this from yesterday’s update:
» Read more

2 comments

Scientists think they have detected a collision in the debris disk surrounding the star Fomalhaut

9:24 am

Fomalhaut asteroid collision
Click for original.

Using the Hubble Space Telescope, astronomers have detected a bright object in the debris disk that surrounds the nearby star Fomalhaut that wasn’t there previously, suggesting it is a glowing cloud of material left over from the collision of two asteroids.

You can read the published paper here [pdf]. Fomalhaut is a young star about 25 light years away, and has one of the best-mapped debris disks known.

The image to the right, reduced to post here, shows this new object, labeled CS2 and detected in 2023. CS1 is a similar detection from 2012 that was initially thought to be an exoplanet. When CS1 faded over time that theory was dismissed, replaced instead with the hypothesis that it was a cloud produced by an asteroid collision.

The recent appearance of CS2 strengthens this hypothesis, which will be further confirmed by future observations that show CS2 fading in the same manner. It also provides scientists a chance to measure the rate of such collisions within Fomalhaut’s debris disk, which scientists believe is essentially a baby solar system in formation. While very uncertain due to the short time scale, this data will help them begin to figure out the rate in which planets will form in such a disk.

One comment

Ancient Martian drainage into crater lake, now turned into ridges

11:41 am

Inverted channels
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on September 9, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels “an inverted channel.” From the caption:

Topographic inversion is a process where geologic features that were once low-lying, like impact craters or riverbeds, become elevated over time, like mesas or ridges. In this process, a crater or channel is filled with lava or sediment that becomes lithified [hardened]. If this infill is more resistant to erosion than the surrounding landscape, the less-resistant material can be eroded away by wind or water. The former crater or valley fill, being more resistant, remains elevated as the landscape around it lowers. The original low-lying feature becomes a mesa or ridge.

In this image, an ancient river network and nearby impact craters have undergone topographic inversion. Impact craters contain round mesas within them, and the stream channel is defined by a network of ridges.

The location of this inverted channel makes its history even more interesting.
» Read more

One comment

A unique place where waves repeatedly crash against each other

11:38 am

The phenomenon this post describes is hard to believe, but a group of bodyboard enthusiasts have discovered a specific spot in the ocean where the underground topography causes waves to smash against each other from four different directions, and do so with such tremendous force that water is flung hundreds of feet into the air.

And it’s not two waves converging – in many cases it’s actually two giant 12-footers colliding with another two smaller waves backwashing out from the shore, plunging simultaneously into a gap left by hydrodynamic forces over a reef close to the surface, causing a huge volume of water to rocket skyward as if a depth charge has gone off underneath the waves.

That footage has got to be seen to be believed, so I have embedded it below. This collision of waves happens again and again, at the same exact spot. There isn’t any unique physics or science going on however. What we are looking at is simply the amazing possibilities that ordinary physics presents to our infinite universe.
» Read more

7 comments

Mars Reconnaissance Orbiter’s high resolution camera takes its 100,000 picture

1:54 pm

Oblique view
Click for original image.

Cool image time! On October 7, 2025, the science team that operates HiRISE, the high resolution camera on Mars Reconnaissance Orbiter (MRO), took its 100,000th picture since entering Mars orbit in March 2006.

The objective of this observation is to better resolve sand dunes and the rocky material underneath them. These dark, eroded rocks may be the source for some of these Syrtis Major sand dunes. Our image was suggested by a high school student enrolled in the Jefferson County Executive Internship program in Colorado in 2023, one of many public outreach programs the HiRISE Team engages in.

To celebrate this accomplishment and the fantastic geology of the scene, students and staff in the HiRISE Photogrammetry lab constructed this digital terrain model. This oblique image highlights the hummocky mounds of the plains that border Jezero Crater, which are among the oldest on Mars.

That oblique image, cropped, reduced, and sharpened to post here, is to the right. The location is about 50 miles to the southwest of Jezero Crater where the rover Perseverance landed.
» Read more

6 comments

Updates on the status of two Mars missions, Maven and Escapade

7:59 pm

NASA today posted two separate updates on the status of two of its missions to or at Mars.

First, it appears there is an issue with one engine on one of the two Escapade orbiters on their way to their parking orbit where they will await the right moment to head to Mars.

During trajectory correction maneuvers for NASA’s twin ESCAPADE spacecraft on Dec. 8 and Dec. 12, the mission operations team noticed low thrust during the burn for one of the spacecraft. The team is working to identify the cause and will attempt a trajectory correction maneuver in the coming weeks.

The other spacecraft has successfully completed its two trajectory correction maneuvers, as planned. Both spacecraft are operating normally otherwise, and currently there are no long-term impacts from the trajectory correction delay.

While not the best news, this issue does not at this moment appear critical.

The second update however was even more negative. It appears engineers have not yet been able to re-establish contact and control of the Mars orbiter Maven.

To date, attempts to reestablish contact with the spacecraft have not been successful. Although no spacecraft telemetry has been received since Dec. 4, the team recovered a brief fragment of tracking data from Dec. 6 as part of an ongoing radio science campaign. Analysis of that signal suggests that the MAVEN spacecraft was rotating in an unexpected manner when it emerged from behind Mars. Further, the frequency of the tracking signal suggests MAVEN’s orbit trajectory may have changed. The team continues to analyze tracking data to understand the most likely scenarios leading to the loss of signal. Efforts to reestablish contact with MAVEN also continue.

It appears the loss of Maven is also impacting communications with the two Mars rovers Curiosity and Perseverance. While NASA has use of three orbiters at present, Mars Reconnaissance Orbiter, Mars Odyssey, and Europe’s Trace Gas Orbiter, to relay data from the ground to Earth, the loss of Maven reduces that communications network by 25%. Engineers are revising plans to make up some of the loss, but operations for both rovers will be for the time being reduced somewhat.

15 comments

The beginnings of a planetary nebula

9:49 am

Calabash Nebula
Click for original image.

Cool image time! The picture to the right, reduced and sharpened to post here, was taken by the Hubble Space Telescope back in 2017 but released this week by NASA’s PR department. It shows what astronomers have nicknamed the Calabash Nebula. From the Wikipedia page:

The Calabash Nebula, also known as the Rotten Egg Nebula or by its technical name OH 231.84 +4.22, is a protoplanetary nebula (PPN) 1.4 light years (13 Pm) long and located some 5,000 light years (47 Em) from Earth in the constellation Puppis. The name “Calabash Nebula” was first proposed in 1989 in an early paper on its expected nebular dynamics, based on the nebula’s appearance.[5] The Calabash is almost certainly a member of the open cluster Messier 46, as it has the same distance, radial velocity, and proper motion.[6] The central star is QX Puppis, a binary composed of a very cool Mira variable and an A-type main-sequence star.

The star in the center is an ancient red giant that is in the initial stages of dying. As it does so it periodically erupts, sending out jets of material from its poles. The result is this elongated shape. According to the release, “the gas shown in yellow is moving close to a million kilometers an hour.”

Over the next few thousand years these eruptions will shape the planetary nebula. Since the central star is actually a binary, those two stars will likely act like the blades in a mixer, adding more interesting forms to the material as it is shot out to form this nebula.

2 comments

Scientists map the outside edge of the Sun’s atmosphere

12:22 pm

The mapping of the Sun's atmosphere

Using multiple solar observatories in space, scientists have now been able to map the approximate location of the outside edge of the Sun’s atmosphere, the point “where the speed of the outward solar wind becomes faster than the speed of magnetic waves.”

The panels to the right are a sampling of that mapping, and is figure 3 of the peer-reviewed paper [pdf]. The bulk of the data (black) comes from five spacecraft observing the Sun from the L1 point a million miles from Earth. The blue line is data from Solar Orbiter, while the red line is data from the Parker Solar Probe. From the press release:

Astronomers have produced the first continuous, two-dimensional maps of the outer edge of the Sun’s atmosphere, a shifting, frothy boundary that marks where solar winds escape the Sun’s magnetic grasp. By combining the maps and close-up measurements, scientists from the Center for Astrophysics | Harvard & Smithsonian (CfA) showed that the boundary grows larger, rougher and spikier as the Sun becomes more active.

…The boundary in the Sun’s atmosphere where the solar wind’s outward speed becomes faster than the speed of magnetic waves, known as the Alfvén surface, is the “point of no return” for material that escapes the Sun and enters interplanetary space; once material travels beyond this point, it cannot travel back to the Sun. This surface is the effective “edge” of the Sun’s atmosphere, and provides scientists with an active laboratory for studying and understanding how solar activity impacts the rest of the solar system, including life and technology on and around Earth.

This new data further refines the nature of the boundary, as earlier probes had already given scientists a rough idea of its size and nature.

2 comments

Abstract art produced by nature within Mars’ north pole ice cap

1:17 pm

Abstract art created by nature on Mars
Click for original

Cool image time! The picture to the right, cropped, reduced, sharpened, and annotated to post here, was taken on October 27, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). I have also rotate the image so that north is to the top.

The science team labels this “Exposure of North Polar Layered Deposits,” an apt description of the horizontal red and grey and blue layers that dominate the image and make this geology look more like an abstract painting than a natural landscape. What we are actually looking at is a canyon 800-to-1,200 feet deep within the north polar ice cap of Mars.

The picture was taken in the summer with the Sun about 12 degrees above the horizon to the south. Thus, the northern cliff face is illuminated, revealing its many colored layers, while the south face is mostly in shadow, hiding those layers.
» Read more

Leave a comment

Engineers lose contact with Mars orbiter Maven

8:48 am

NASA announced late yesterday that the engineering team running the Maven Mars orbiter lost contact with the spacecraft on December 6, 2025, and are still trying to figure out what happened and regain communications.

NASA’s MAVEN (Mars Atmosphere and Volatile EvolutioN) spacecraft, in orbit around Mars, experienced a loss of signal with ground stations on Earth on Dec. 6. Telemetry from MAVEN had showed all subsystems working normally before it orbited behind the Red Planet. After the spacecraft emerged from behind Mars, NASA’s Deep Space Network did not observe a signal.

The spacecraft and operations teams are investigating the anomaly to address the situation. More information will be shared once it becomes available.

No other information was released.

One comment

A small galaxy with lots of massive stars

9:54 am

A small galaxy with many massive stars
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 and released this week as the European Space Agency’s (ESA) Hubble picture of the week.

This dwarf galaxy, 13 million light years away, is called Markarian 178 (Mrk 178). Though much smaller than the Milky Way, it is packed with massive stars. From the caption:

While the bulk of the galaxy is blue owing to an abundance of young, hot stars with little dust shrouding them, Mrk 178 gets a red hue from a collection of massive stars, which are especially concentrated in the brightest, reddish region near the galaxy’s edge. This azure cloud is home to a large number of rare objects called Wolf–Rayet stars. Wolf–Rayet stars are massive stars that are casting off their atmospheres through powerful winds. Because Mrk 178 contains so many Wolf–Rayet stars, the bright emission lines from these stars’ hot stellar winds are etched upon the galaxy’s spectrum. Particularly ionised hydrogen and oxygen appear as a red colour to Mrk 178 in this photo, observed using some of Hubble’s specialised light filters.

Massive stars enter the Wolf–Rayet phase 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 neighbours that could have stirred up its gas to form new stars. Astronomers believe that it was triggered by the interaction with a smaller satellite, as revealed by the presence of low surface brightness tidal features detected around Mrk 178 in deep imaging acquired with the Large Binocular Telescope.

And yet, these observations do not see this small satellite galaxy. It has either been completely absorbed into Mrk 178, or maybe this theory for explaining this dwarf galaxy’s make-up is flawed.

One comment

Perseverance moves west, into the barren hinterlands beyond Jezero Crater

1:56 pm

Perseverance looking west
Click for full resolution. Original images can be found here and here.

Overview map
Click for interactive map.

Cool image time! The panorama above was created using two pictures taken on December 4, 2025 (here and here) by the navigation camera on the Mars rover Perseverance. The view I think is looking west, away from the rim of Jezero Crater, which now lies behind the rover to the east.

The blue dot on the overview map to the right marks Perseverance’s position when it took this picture. The yellow lines indicate my rough guess as to the area covered by the panorama. The white dotted line marks the actual route the rover has taken, while the red dotted line the original planned route.

As I noted in my previous Perseverance update in mid-November, the science team has apparently decided to revise the route, abandoning initial plan of going back uphill towards the rim and instead travel downhill into the hills beyond. This is a region that orbital data has suggested might be rich in minerals, making it a prime mining location for future colonists. My guess is that the science team decided they needed to get there, that they had enough data from the rim and that it was now more important to get to the western mineralogy.

Though I am sure they are using the highest resolution orbital images from Mars Reconnaissance Orbiter (MRO) to guide them, the Perseverance team has not yet upgraded its interactive location map to show those details in this western region. Thus, the map in this area is fuzzy and not as detailed.

The team has also not published its revised planned route, so there is no way to guess where the rover will go next. It does appear however that it is finally leaving Jezero Crater for good.

And as all recent pictures from Perseverance, these images show this Martian landscape to be utterly barren, its hills and valleys softened by dust and eons of erosion from the very thin Martian wind. This is an alien place, though it has the potential with human ingenuity to bloom if we have the courage to try.

5 comments

New data strengthens the conflict in the observed value for the universe’s expansion rate

11:49 am

Graphic showing the conflict
Click for original.

The uncertainty of science: New research using a combination of ground- and space-based telescopes has not only failed to resolve the difference between the two values observed for the Hubble constant (the expansion rate of the universe), it actually confirms that conflict.

The graphic to the right nicely illustrates the conflict. Observations from the early universe come up with a value of 67-68 kiloparsecs per second per megaparsec for the Hubble constant. Observations from the present universe, including these new more precise measurements, come up with a value of 73-74. From the press release:

A team of astronomers using a variety of ground and space-based telescopes including the W. M. Keck Observatory on Maunakea, Hawaiʻi Island, have made one of the most precise independent measurements yet of how fast the universe is expanding, further deepening the divide on one of the biggest mysteries in modern cosmology.

Using data gathered from Keck Observatory’s Cosmic Web Imager (KCWI) as well as NASA’s James Webb Space Telescope (JWST), the Hubble Space Telescope (HST) the Very Large Telescope (VLT), and European Organisation for Astronomical Research in the Southern Hemisphere (ESO) researchers have independently confirmed that the universe’s current rate of expansion, known as the Hubble constant (H₀), does not match values predicted from measurements from the universe when it was much younger.

Cosmologists call this conflict “the Hubble Tension”, a absurd fake term expressly designed to hide the fact that they have no idea what’s going on. It isn’t “tension”, it is a perfect example of good observations coming up with contradictory data that no theory can explain.

15 comments

New images of interstellar Comet 3I/Atlas

9:56 am

New Hubble image of 3I/Atlas
Click for original.

Juice image of 3I/Atlas
Click for original.

Both NASA and the European Space Agency (ESA) yesterday released new photos of the interstellar comet 3I/Atlas.

First, NASA released the image on the right, taken on November 30, 2025 by the Hubble Space Telescope. At the time the comet was about 178 million miles away. It clearly shows the comet’s coma of material, surrounding a bright nucleus at the center. The streaks are background stars.

Next, the mission team for Europe’s Juice probe, on its way to Jupiter, released one small portion of a picture taken by its navigation camera. That picture is the second to the right.

During November 2025, ESA’s Jupiter Icy Moons Explorer (Juice) used five of its science instruments to observe 3I/ATLAS. The instruments collected information about how the comet is behaving and what it is made of. In addition, Juice snapped the comet with its onboard Navigation Camera (NavCam), designed not as a high-resolution science camera, but to help Juice navigate Jupiter’s icy moons following arrival in 2031.

Though the data from the science instruments won’t arrive on Earth until February 2026, our Juice team couldn’t wait that long. They decided to try downloading just a quarter of a single NavCam image to see what was in store for them. The very clearly visible comet, surrounded by signs of activity, surprised them.

Not only do we clearly see the glowing halo of gas surrounding the comet known as its coma, we also see a hint of two tails. The comet’s ‘plasma tail’ – made up of electrically charged gas, stretches out towards the top of the frame. We may also be able to see a fainter ‘dust tail’ – made up of tiny solid particles – stretching to the lower left of the frame.

The image was taken on 2 November 2025, during Juice’s first slot for observing 3I/ATLAS. It was two days before Juice’s closest approach to the comet, which occurred on 4 November at a distance of about 66 million km.

Because Juice is presently behind the Sun (as seen from Earth), most of the data it collected during its closest approach won’t be downloaded until February. This one partial image is only a fore taste.

3 comments

The insane terrain inside Mars’ Death Valley

12:30 pm

taffy terrain
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on October 27, 2025 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this a “twisted surface,” to which I think we all can agree. What we are looking at is a geological feature found only on Mars in only one region that has been labeled “taffy terrain” by scientists. According to a 2014 paper, the scientists posit that this material must be some sort of “a viscous fluid,” naturally flowing downward into “localized depressions.” Because of its weird nature I have posted many cool images of it in the past (see here, here, here, here, here, and here).

In the case of the image to the right, the red dot marks the peak of a small knob, with the green dot on the upper left the low point about 900 feet below. As you can see, the taffy has migrated into the depressions, as some flowing material would.
» Read more

2 comments

Ground-based telescope actually photographs an exoplanet

10:51 am

exoplanet imaged directly
Click for original movie.

Using a new instrument on the Subaru Telescope in Hawaii astronomers have not only discovered a massive exoplanet orbiting a star, they have been able to actually photograph the planet itself.

The arrow in the picture to the right shows that planet. That picture is a screen capture from a short movie complied from five observations taken over several months earlier this year, showing the planet as it orbited the star, the light of which is blocked out so as to not blind the camera. From the press release:

The newly discovered planet, HIP 54515 b, orbits a star 271 light-years away in the constellation Leo. With nearly 18 times Jupiter’s mass, it circles its star at about Neptune’s distance from our Sun. But the star and planet appear very close when seen from Earth; roughly the size that a baseball seen 100 km away would appear. The SCExAO system produced extremely sharp images allowing us to see the planet.

The astronomers also used this new instrument to image a brown dwarf star with a mass equivalent to sixty Jupiters about 169 light years away.

3 comments
1 2 3 … 32