Tag: science

Momentus and Astroscale team up to propose Hubble servicing mission

11:29 am

Capitalism in space: The two orbital tug companies Momentus and Astroscale announced today that they have partnered to propose a servicing mission to the Hubble Space Telescope, designed to boost the telescope and extend its life.

The proposed mission concept, a commercial solution to extend the life of this important national asset without risk to humans, includes launching a Momentus Vigoride Orbital Service Vehicle (OSV) to low-Earth orbit on a small launch vehicle. Once on orbit, Astroscale’s RPOD technology built into the OSV would be used to safely rendezvous, approach and then complete a robotic capture of the telescope. Once mated, the OSV would perform a series of maneuvers to raise the Hubble by 50 km. Removal of surrounding and threatening space debris in Hubble’s new orbit using the Vigoride and Astroscale’s RPOD capabilities will be prioritized after the completion of the primary reboost mission.

As I have written repeatedly, Hubble is a telescope that refuses to die. I predicted that come the 2030s, when its orbit had decayed to a point that it either had to be de-orbited (NASA’s preferred option in the past when it ran everything) or be lifted to a higher orbit to extend its life, people would find a way to lift it.

Now that private enterprise is running the show, NASA is taking advantage of that to ask for private solutions to save Hubble, and not surprisingly it is quickly getting them.

4 comments

Paperwork on Mars

11:20 am

Paperwork on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on April 15, 2023 by the close-up camera on the Mars rover Curiosity. From the caption:

NASA’s Curiosity Mars rover took this close-up view of a rock nicknamed “Terra Firme” that looks like the open pages of a book, on April 15, 2023, the 3,800th Martian day, or sol, of the mission, using the Mars Hand Lens Imager (MAHLI) on the end of its robotic arm. The rock is about an inch across (2.5 centimeters).

Strange looking rocks like this have not been rare during Curiosity’s travels in Gale Crater, though it seems to me that the variety and strangeness has increased as the rover has climbed higher on Mount Sharp. In this case, the tall flake in the center — as well as the shorter flakes to the left — were among the many thin layers seen in this area. These layers however were clearly made of much harder material than the layers above and below. Those weaker layers eroded away over the eons, leaving behind these thin sheets.

Also, if you own red-blue 3D glasses, take a look at the anaglyph here.

3 comments

Webb takes infrared image of the disk of dust and debris surrounding Fomalhaut

4:57 pm

Fomalhaut debris disk as seen in the infrared by Webb
Click for original image.

Using the mid-infrared instrument on the Webb Space Telescope, astronomers have obtained a new high resolution infrared image of the disk of dust and debris that surrounds the star Fomalhaut, and (surprise!) have it to be more complex than they previously believed.

That image is to the right, annotated by the science team.

Overall, there are three nested belts extending out to 14 billion miles (23 billion kilometers) from the star; that’s 150 times the distance of Earth from the Sun. The scale of the outermost belt is roughly twice the scale of our solar system’s Kuiper Belt of small bodies and cold dust beyond Neptune. The inner belts – which had never been seen before – were revealed by Webb for the first time.

The dust cloud identified in the outer ring is possibly left over from a recent collusion of larger bodies.

Leave a comment

Sinuous ridge inside Martian canyon

9:25 am

Sinuous ridge inside a Martian canyon
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on February 7, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the camera team labels a “sinuous ridge within valley.”

The location is at 30 degrees south latitude, right on the edge of the southern of the two 30-60 degree mid-latitude bands where orbital images show many glacial features. Closer to the equator and there is little or no evidence of near surface ice on Mars. Farther from the equator from this latitude and the evidence of near surface ice increases, becoming very dominant the closer to the poles you get.

At this spot, it appears there is little near surface ice. The channel has ripple sand dunes inside it, and the sinuous ridge appears to be bedrock. Similarly, the plateau above the channel also appears like bedrock, the craters showing no evidence of splatter that is common where there is near surface ice.

What made the channel? And what made that a sinuous ridge inside it?
» Read more

Leave a comment

Rocket Lab successfully launches two NASA hurricane monitoring cubesats

6:11 pm

Rocket Lab’s Electron rocket today successfully placed NASA’s two Tropics hurricane monitoring cubesats into orbit, lifting off from New Zealand ((May 8th New Zealand time).

This is the first of two Rocket Lab launches to get the entire four-satellite Tropics constellation into orbit, with the second schedule for two weeks from now.

The leaders in the 2023 launch race:

29 SpaceX
16 China
6 Russia
4 Rocket Lab

American private enterprise now leads China 33 to 16 in the national rankings, and the entire world combined 33 to 28.

One comment

Brain terrain on top of Martian mountains

12:28 pm

Brain terrain at high elevation on Mars
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on March 26, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It is labeled by the scientists “Brain Terrain on Floor of Crater in Warrego Valles.”

Brain terrain is a geological feature entirely unique to Mars that remains unexplained in any way by geologists. The scientists know it is almost certainly related to near-surface ice and its sublimation into gas, but their theories as to its precise formation process remain incomplete and unconvincing, even to them.

In this case the brain terrain’s interweaving nodules seem to show flow patterns, but strangely those patterns go around depressions and hollows. Yet, the overall flow direction also seems to point downhill towards the slope on the image’s right edge.
» Read more

5 comments

Hubble captures shadows on star’s outer accretion disk cast by inner accretion disk

11:07 am

Shadows cast on star's accretion disk
Click for original image.

Astronomers using the Hubble Space Telescope’s images taken five years apart have captured the changing shadows cast by a star’s inner accretion disk onto its outer accretion disk.

Those images are to the right, reduced and rearranged to post here. From the caption:

Comparison images from the NASA/ESA Hubble Space Telescope, taken several years apart, have uncovered two eerie shadows moving counterclockwise across a disc of gas and dust encircling the young star TW Hydrae. The discs are tilted face-on as seen from Earth and so give astronomers a bird’s-eye view of what’s happening around the star.

The [top] image, taken in 2016, shows just one shadow [A] at the 11 o’clock position. This shadow is cast by an inner disc that is slightly inclined to the outer disc and so blocks starlight. The picture on the [bottom] shows a second shadow that emerged from yet another nested disc at the 7 o’clock position, as photographed in 2021. What was originally the inner disc is marked [B] in this later view.

The shadows rotate around the star at different rates like the hand on a clock. They are evidence for two unseen planets that have pulled dust into their orbits. This makes them slightly inclined to each other. This is a visible-light photo taken with the Space Telescope Imaging Spectrograph. Artificial colour has been added to enhance details.

An artist’s conception of the system, as seen from an oblique angle, is available here. All told, this solar system of disks kind of resembles a spinning gyroscope, with its different rings tilted at different angles to conserve angular momentum.

2 comments

Weird dome near Starship candidate landing zone on Mars

1:47 pm

Weird dome near Starship candidate landing zone on Mars
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on February 27, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label as domes in Arcadia Planitia, one of the many large northern lowland plains of Mars.

This to me is a “What the heck?” image. I won’t dare try to explain the warped concentric ringed pattern at the top of the mesa, nor the bright and dark splotch that surrounds it. The small craters around it appear to have glacier material within them, and the terrain here likely has a lot of near surface ice, being at 37 degrees north latitude in a region where the data suggests such ice exists. The different colors here likely indicate the difference between dust (orange) and coarser material (aqua).

The location, as shown in the overview map below, makes this mesa more tantalizing.
» Read more

5 comments

Two interacting galaxies, both with active supermassive black holes at their center

10:20 am

Interacting galaxies
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken by the Hubble Space Telescope and released today. From the caption:

This new image from NASA’s Hubble Space Telescope shows interacting galaxies known as AM 1214-255. These galaxies contain active galactic nuclei, or AGNs. An AGN is an extraordinarily luminous central region of a galaxy. Its extreme brightness is caused by matter whirling into a supermassive black hole at the galaxy’s heart.

Hubble observed the galaxy [on the right] as part of an AGN survey, with the aim of compiling a dataset about nearby AGNs to be used as a resource for astronomers investigating AGN physics, black holes, host galaxy structure, and more.

Note how the outer arms of both galaxies appear warped, with long streams of stars being pulled towards the other galaxy. Imagine living on a planet orbiting one of those stars as it finds itself over time farther and farther from its home galaxy, out in the vast emptiness of intergalactic space. While this sounds lonely, it has advantages for life, because isolated from the galaxy the star will not be threatened by supernovae, gamma ray bursts, and the host of other events that happen inside galaxies that can threaten biology.

It also means your night sky will be heralded by the rising and setting of two nearby giant galaxies.

5 comments

In a Martian cold cauldron, boil and bake

1:25 pm

bubbles and boiling ground
Click for original image.

Cool image time! My headline paraphrases slightly the witches’ chant from Shakespeare’s MacBeth, if only to make it more accurately describe the picture to the right, cropped and reduced to post here. Taken on January 5, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), it shows a patch of mid-latitude terrain in the icy northern lowland plains of Mars.

While some of the craters here were certainly caused by impact, it is also likely that most were instead cryo-volcanic in nature, whereby ice bubbles up from below as changing temperature conditions — none of which need to be very warm — cause it to either melt temporarily into liquid or sublimate directly into a gas. The dark pimplelike hole on the picture’s right edge is a perfect example, with the hole sitting at the top of a cone.
» Read more

Leave a comment

SuperBIT balloon circling Antarctica snaps more high resolution astronomical pictures

9:39 am

Sombrero Galaxy
Click for full image.

The Super-Pressure Balloon Imaging Telescope (Super-BIT) that has been circling Antarctica for the last two weeks has now obtained two more more high resolution wide-field astronomical pictures.

The picture to the right, cropped to post here, is of Messier 104 (the Sombrero Galaxy). While the telescope cannot zoom in closer than this to such objects, it is able to get much wider and sharp pictures, covering an entire galaxy or nebula that ground-based telescope using adaptive optics (designed to counter the fuzziness caused by the atmosphere) cannot. Adaptive optics only work on very small fields of view, thus making it unable to observe some of the larger nearby astronomical objects like galaxies and nebulae.

If you look at the live stream of the balloon’s track, it has now almost completed its second circuit of Antarctica.

3 comments

Astronomers record moment star eats planet

9:25 am

Animation of a star eating a planet
Click to watch full animation.

Using data from a variety of space- and ground-based telescopes, astronomers now think they have recorded the moment a star similar to our Sun actually swallowed a planet thought to be comparable to Jupiter or smaller.

Once the science team put all the evidence together, they realized the dust they were seeing with NEOWISE [in orbit] was being generated as the planet spiraled into the star’s puffy atmosphere. Like other older stars, the star had begun to expand in size as it aged, bringing it closer to the orbiting planet. As the planet skimmed the surface of the star, it pulled hot gas off the star that then drifted outward and cooled, forming dust. In addition, material from the disintegrating planet blew outward, also forming dust.

What happened next, according to the astronomers, triggered the flare of optical light seen by ZTF [survey telescope in California]. “The planet plunged into the core of the star and got swallowed whole. As it was doing this, energy was transferred to the star,” De explains. “The star blew off its outer layers to get rid of the energy. It expanded and brightened, and the brightening is what ZTF registered.”

Some of this expanding stellar material then escaped from the star and traveled outward. Like the boiled-off layers of the star and planet that previously drifted outward, this material also cooled to form dust. NEOWISE is detecting the infrared glow of all the newly minted dust.

The picture above is a screen capture from a short artist’s animation created to illustrate what happened. The most amazing aspect of this event is how long the planet skimmed the surface of that star. It appears it did so for several orbits at least.

2 comments

The cliff wall of ancient Martian lava channel

3:32 pm

The cliff wall of an ancient Martian lava channel
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on January 17, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) by the camera team not as part of any particular research project but in order to fill a gap in the camera’s schedule so as to maintain its proper temperature. In such cases the camera team tries to pick potentially interesting spots.

This cliff, about 1,100 feet high, is the north wall of a major volcano channel flowing across the Tharsis Bulge, the lava plains that surround Mars’ giant volcanoes. Located in the dry equatorial regions, there is no near surface ice here, but a lot of dust, much of it likely volcanic ash. In the full picture are several ancient craters, all of which are almost entirely buried by this dust and ash.

The cliff wall itself is made up of numerous layers, each representing a past volcanic flood lava event that covered this region with a new flow of material. These events occurred over more than a billion years.
» Read more

One comment

Sunspot update: April activity drops steeply

2:19 pm

NOAA this week once again published an update of its monthly graph that tracks the number of sunspots on the Sun’s Earth-facing hemisphere. As I do every month, I have posted this graph below, with some additional details included to provide some context.

In April the number of sunspots dropped again, for the second time in the past three months. The high activity previously had suggested that the solar maximum was going to be much higher than predicted, or possibly would come sooner than expected. The drop however now suggests that the fast rise in sunspot activity that we have seen since the beginning of the ramp up to solar maximum in 2020 might finally be abating.
» Read more

7 comments

A nearby aging galaxy with an active supermassive black hole at its center

9:44 am

aging galaxy
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 and released today. It shows a galaxy only 30 million light years away, making almost our neighbor. From the caption:

NGC 3489 has an active galactic nucleus, or AGN. The AGN sits at the center of the galaxy, is extremely bright, and emits radiation across the entire electromagnetic spectrum as the black hole devours material that gets too close to it.

This lenticular galaxy is a Seyfert galaxy, which is a class of AGN that is dimmer than other types of AGNs. They generally don’t outshine the rest of the galaxy, so the galaxy surrounding the black hole is clearly visible. Other types of AGNs emit so much radiation that it is almost impossible to observe the host galaxy.

That active nucleus is the bright dominate sphere at the galaxy’s center, large enough to overwhelm a large percentage of the rest of the galaxy. Its existence and dominance suggests that this galaxy is aging, and is beginning the transition from a spiral to an elliptical. In fact, its arms have already mostly vanished, and there is at present little star-formation on-going.

2 comments

Suborbital rocket explodes four seconds after launch in New Mexico

9:15 am

An UP Aerospace suborbital rocket exploded yesterday only four seconds after launch in New Mexico, destroying a number of private and NASA science and commercial payloads.

An UP Aerospace rocket, 20 feet tall and carrying a NASA payload, exploded moments after liftoff today. The unfortunate event not only affected the NASA TechRise Student Challenge payloads but also delayed a poignant tribute to the late NASA astronaut, Phillip K. Chapman, and chemist Louise Ann O’Deen.

The rocket was set to launch the cremated remains of Chapman, NASA’s first Australian-born American astronaut, finally granting him his long-awaited journey to space.

Chapman and O’Deen’s remains were payloads from the commercial company Celestis. The thirteen NASA payloads were part of its TechRise Student Challenge program for 6th to 12th grade students.

Leave a comment

Exploring just one small corner of Valles Marineris, Mars’ Grand Canyon

2:11 pm

One corner of Valles Marineris
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on February 19, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the many many many layers that are found in the cliffs of Valles Marineris, the largest known canyon in the solar system and far far larger that Earth’s Grand Canyon.

The elevation difference between the red dots is just under 4,000 feet. Yet that high point is still more than 7,000 feet below the rim of the canyon, more than thirty miles to the south. And the lower dot is still about 18,000 feet above the low point in this side canyon of Valles Marineris, about thirty miles away to the northeast.

In other words, in sixty miles from rim to floor the canyon at this location drops about 25,000 feet, only 4,000 feet less than the height of Mount Everest. Compare that with the Grand Canyon’s slopes, which drops in eleven miles about 5,000 feet, beginning at the main south rim lookout at the start of Bright Angel trail.
» Read more

Leave a comment

Galaxies without end

9:44 am

Galaxies without end
Click for full image.

Cool image time! The picture to the right has been significantly reduced but also significantly sharpened to post here. It was taken by the Hubble Space Telescope as part of a recent survey of “jellyfish” galaxies, galaxies located in galaxy clusters where there is a large concentration of galaxies whose combined gravity and intergalactic environment acts to pull material or “tendrils” out from the galaxy.

Rather than crop the image to focus on that single large central jellyfish galaxy, I have instead sharpened the much-reduced full photo to bring out clearly the number of surrounding galaxies. There is only one Milky Way star in this picture, the object with the four diffraction spikes in the lower-right. Every other dot is a galaxy, many of which can be seen to be very strangely shaped in the original full resolution image. In fact, I strongly recommend you click on the picture to explore that original image, just to see the variety of galaxy shapes.

The point of this picture today however is not to illustrate the wide variety of galaxies that can exist, but to underline the vast and largely incomprehensible scale of the universe. The large galaxy is thought to be 650 million light years away, which means it took light traveling at 186,000 miles per second that many years to get here. The surrounding galaxies are also all tens to hundreds of millions of light years from each other. Yet, their combined gravity, almost infinitesimal in strength, is enough to warp the shape of each.

We understand these numbers and facts intellectually, but do we understand them in reality? I think it is difficult, even if you work hard to come up with a scaled comparison. For example, it took nine years for the New Horizons spacecraft to get from Earth to Pluto, a distance of about 4.5 light hours. And New Horizons was the fastest traveling probe ever launched, moving at 36,400 miles per hour when it left Earth. Yet, this distance is nothing compared to the distance between these galaxies.

The vastness of existence really is beyond our comprehension. That we try to comprehend it speaks well of the human desire to achieve the impossible.

4 comments

Radar antenna on Europe’s JUICE probe to Jupiter stuck

8:27 am

European Space Agency officials revealed yesterday that the 52-foot radar antenna on its JUICE probe to Jupiter has failed to deploy as planned, and that they are attempting to shake what they think is a small pin free that is in the way.

Engineers suspect a tiny pin may be protruding. Flight controllers in Germany plan to fire the spacecraft’s engine in hopes of shaking the pin loose. If that doesn’t work, they said they have plenty of time to solve the problem.

Juice, short for Jupiter Icy Moons Explorer, won’t reach the giant planet until 2031. It’s taking a roundabout path to get there, including gravity-assist flybys of Earth and our moon, and Venus.

The radar antenna is needed to peer beneath the icy crust of three Jupiter moons suspected of harboring underground oceans and possibly life, a major goal of the nearly $1.8 billion mission. Its targets include Callisto, Europa and Ganymede, the largest moon in the solar system.

If this antenna cannot be freed, it will prevent JUICE from doing one of its prime missions.

11 comments

Glacier layers on the border of Hellas Basin

12:20 pm

Dipping glacial layers
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on February 21, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label as “dipping layers”, referring specifically to the mesas with the terraces on their western flanks.

The layers obviously signify past cycles of geological events on Mars. That the terraces are only on one side of the mesas suggests that they are tilted, with the downhill grade to the east.

These layers however pose several mysteries. First, why are they located so specifically in only certain places of this region? It appears that the layered terrain is only found in the lower hollows and valleys. Why?

Second, why are they tilted at all?
» Read more

Leave a comment

If global warming doesn’t kill us the fog will!

11:01 am

Shipping routes
Illustration showing the distance and time saved by going north
through the Arctic Ocean

A new report published by the American Geophysical Union, and touted by it though a press release today, says that while the melting Arctic Ocean icecap — caused by human-caused global warming — will make shipping more convenient, that shipping will be hindered by increased fog — caused by human-caused warming.

Arctic sea ice has been shrinking for decades. That loss has opened shipping channels in the Northwest Passage and the Northern Sea Route, allowing even non-icebreaker vessels to skip the time-consuming Panama and Suez Canals farther south. But as the ice recedes, cold air is exposed to more warm water, and warm vapor condenses into fog in those new passages. Hidden chunks of ice already pose risks to vessels making their way through foggy, low-visibility routes.
» Read more

59 comments

Astronomers discover 25 more repeating fast radio bursts, doubling the number known

10:18 am

Using a ground-based radio telescope in Canada that scans the northern sky each night, astronomers have discovered another 25 repeating fast radio bursts (FRBs), doubling the number that was previously known.

One surprising aspect of this new research is the discovery that many repeating FRBs are surprisingly inactive, producing under one burst per week during CHIME’s observing time. Pleunis believes that this could be because these FRBS haven’t yet been observed long enough for a second burst to be spotted.

The cause of FRBs still remains unsolved. The knowledge of specific repeating FRBs however will go a long way to figuring out this mystery, because other telescopes will be able to better observe later bursts, knowing when they are expected to occur.

Leave a comment

Engineers extend Voyager-2’s life by tapping into reserve power supply

9:54 am

Engineers have begun using a backup power supply on the Voyager-2 spacecraft — launched in 1977 and presently traveling in interstellar space — in order to extend the life of one of its five instruments one additional year.

To help keep those instruments operating despite a diminishing power supply, the aging spacecraft has begun using a small reservoir of backup power set aside as part of an onboard safety mechanism. The move will enable the mission to postpone shutting down a science instrument until 2026, rather than this year.

The solution is only temporary, as the end of the mission is inevitable as its radioisotope thermoelectric generator (RTG) was only designed to provide power for about a half century (!). As time passes its power supply slowly declines, forcing engineers in recent years to shut down other systems to allow the science instruments to operate. That all the other systems on both Voyager-1 and Voyager-2 remained operational until the end of their RTGs tells us how well these spacecraft were built by their 1970s creators.

Assuming this works, engineers will do the same thing on Voyager-1 sometime next year. In both cases, however, power from the RTGs will likely run out entire sometime in the next 5-10 years, ending the missions.

11 comments

Frozen waves of lava on Mars

12:19 pm

Frozen waves of lava on Mars

Cool image time! The picture to the right, cropped and reduced to post here, was taken on January 15, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows an area where the ground suddenly transitions from a crazy quilt of criss-crossing hollows and ridgelines to a very flat and smooth plain.

The location is at 21 degrees south latitude, so this is in the dry equatorial regions. Though it has a small resemblance to the chaos terrain that is found in many places on Mars, mostly in the mid-latitudes where glaciers are found, the scale here is too small and the ridges and canyons are not as sharply drawn. While chaos terrain usually forms sharply defined large flat-topped mesas with steep cliffs, here the ridges are small and the slopes to the peaked tops are somewhat gentle.
» Read more

Leave a comment

Experimental NASA high altitude balloon circles Antarctica in ten days

10:06 am

Overview map
Click for original image.

An experimental NASA high altitude balloon has successfully circled the continent of Antarctica in only ten days, flying at an average elevation of 107,000 feet.

The overview map to the right, annotated for posting here, shows its flight path so far.

“The balloon is performing exactly the way it was engineered to do, maintaining its shape and flying at a stable altitude despite the heating and cooling of the day-night cycle,” said Debbie Fairbrother, NASA’s Scientific Balloon Program chief. “As we continue to test, validate, and qualify this technology for future flights we’re also performing some cutting-edge science.”

The balloon is flying the Super Pressure Balloon Imaging Telescope (SuperBIT) payload, which has already returned brilliant research images from this flight.

Weather permitting, the balloon can be seen from the ground, especially at sunrise and sunset, as it continues on its globetrotting journey. People can track the real-time location of NASA’s super pressure balloon at this website: https://www.csbf.nasa.gov/map/balloon10/flight728NT.htm

The images have so far been of astronomical objects, such as the Antennae galaxy and the Tarantula nebula. Being so high above the atmosphere, the pictures are sharper than ground-based telescopes and have a much wider field of view.

The press release did not state how long this flight will last, but it did mention a second balloon mission is planned, flying a European cosmic-ray detector.

4 comments

The inexplicable tail of the asteroid Phaethon is from sodium, not dust

9:39 am

For years astronomers have puzzled over the strange behavior of the asteroid Phaethon, which though rocky would still produce a tail like a comet whenever its orbit took it close to the Sun.

New research by astronomers using several space telescopes designed to study the Sun has determined that this tail is made of sodium, not dust as previously believed, which also suggests that many of the other “comets” these solar telescopes have detected close to the Sun might instead be asteroids like Phaeton.

Hoping to find out what the tail is really made of, Zhang looked for it again during Phaethon’s latest perihelion in 2022. He used the Solar and Heliospheric Observatory (SOHO) spacecraft — a joint mission between NASA and the European Space Agency (ESA) – which has color filters that can detect sodium and dust. Zhang’s team also searched archival images from STEREO and SOHO, finding the tail during 18 of Phaethon’s close solar approaches between 1997 and 2022.

In SOHO’s observations, the asteroid’s tail appeared bright in the filter that detects sodium, but it did not appear in the filter that detects dust. In addition, the shape of the tail and the way it brightened as Phaethon passed the Sun matched exactly what scientists would expect if it were made of sodium, but not if it were made of dust.

Knowing these new facts, it might make it possible to map the asteroids that orbit very close to the Sun but are hard to detect optically using standard telescopes because of the Sun’s brightness. Instead, astronomers might be able to map them using these solar telescopes.

One comment

One instrument on Mars Reconnaissance Orbiter ends its mission

9:00 am

Because Mars Reconnaissance Orbiter’s (MRO) CRISM instrument needed to be cooled to low temperatures to use infrared wavelengths for detecting underground minerals and ice on Mars, and the cryocoolers have run out of coolant, the science team has shut the instrument down.

In order to study infrared light, which is radiated by warm objects and is invisible to the human eye, CRISM relied on cryocoolers to isolate one of its spectrometers from the warmth of the spacecraft. Three cryocoolers were used in succession, and the last completed its lifecycle in 2017.

All the remaining instruments on MRO, including its two cameras, continue to operate nominally.

In its final task, CRISM produced a global map showing water related minerals on Mars, released last year, and a global map showing iron deposits, to be released later this year.

One comment

The breakup of a Martian glacier

11:48 am

The breakup of a Martian glacier
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on January 29, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists label a “contact” in the glacier country in the northern mid-latitudes of Mars.

The contact is clearly the region of breakup in the middle of the picture. To the right the surface is whole and very smooth. As we move to the left that surface begins to show cracks and holes until those holes and cracks eliminate that surface entirely, revealing a lower layer that is soft-looking and stippled.

In other words, this is the edge of a glacier, and is the place in which it is breaking up. Unlike Earth glaciers however this breakup process is entirely different.
» Read more

Leave a comment

Hakuto-R1 lands on Moon but ceases communications at touchdown

10:16 am

Lunar map showing Hakuto-R1's landing spot
Hakuto-R1’s planned landing site is in Atlas Crater.

According to the Hakuto-R1 engineering team, the lander provided full data and maintained communications right up until touchdown, but at that point they lost contact with the spacecraft.

The loss of data at landing suggests something went wrong at touchdown. That they were able to maintain contact until then, and the data appeared correct, suggests that the spacecraft descended properly into Atlas Crater, but then touched down on some rough ground that either caused it to topple, or damaged it on contact.

This remains speculation however. We will have to wait for a full update from Ispace.

This was a engineering mission to test the company’s spacecraft design and its ability to operate a lunar mission. The failure at landing means it achieved about 8 to 9 of its 10 milestones. How this final failure will effect its next mission as well as its contract with NASA remains unclear.

9 comments

Review of InSight data allows scientists to further refine their model of Mars’ interior

10:04 am

Using archive data from the now defunct InSight Mars lander, especially two seismic detections that came from the planet’s far side, scientists now believe that Mars’ central core is significantly different than Earth’s, being entirely liquid and made up of much lighter materials than expected.

To determine these differences, the team tracked the progression of two distant seismic events on Mars, one caused by a marsquake and the other by a large impact, and detected waves that traveled through the planet’s core. By comparing the time it took those waves to travel through Mars compared to waves that stayed in the mantle, and combining this information with other seismic and geophysical measurements, the team estimated the density and compressibility of the material the waves traveled through. The researchers’ results indicated that Mars most likely has a completely liquid core, unlike Earth’s combination of a liquid outer core and solid inner core.

Additionally, the team inferred details about the core’s chemical composition, such as the surprisingly large amount of light elements (elements with low atomic numbers)—namely sulfur and oxygen—present in Mars’ innermost layer. The team’s findings suggested that a fifth of the core’s weight is made up of those elements. This high percentage differs sharply from the comparatively lesser weight proportion of light elements in Earth’s core, indicating that Mars’ core is far less dense and more compressible than Earth’s core, a difference that points to different conditions of formation for the two planets.

These differences, if confirmed, would certainly affect the way Mars’ surface evolved over the eons, and might help explain its giant volcanoes as well as the planet’s lack of a magnetic field.

The results however remain uncertain, because InSight provided only one seismometer on Mars. To better triangulate the data will require more than one, in the future.

2 comments
1 … 34 35 36 37 38 … 274