Tag: asteroids

New Webb data says asteroid 2024 YR4 will miss the Moon in 2032

2:54 pm

Asteroid 2024 YR4 as seen by Webb in the mid-infrared
Asteroid 2024 YR4 as seen by Webb in the
mid-infrared in April 2025. Click for original image.

New Webb data collected in February has now eliminated any chance the potentially dangerous asteroid 2024 YR4 will hit either the Earth or the Moon when it makes its next close pass on December 22, 2032.

Using data from NASA’s James Webb Space Telescope observations collected on Feb. 18 and 26, experts from NASA’s Center for Near-Earth Object Studies at the agency’s Jet Propulsion Laboratory in Southern California have refined near-Earth asteroid 2024 YR4’s orbit and are ruling out a chance of lunar impact on Dec. 22, 2032. With the new data, 2024 YR4 is expected to pass by the lunar surface at a distance of 13,200 miles (21,200 km).

Earlier less precise data had suggested 2024 YR4 had a 4.3% chance of hitting the Moon in 2032. That chance is now zero. This result is actually disappointing, in that an impact of this asteroid, estimated to be about 200 feet in diameter, would have not only been spectacular, but would have been scientifically useful. We would have been able to observe it closely with many ground- and space-based telescopes, and garnered a lot of useful information about the asteroid, the Moon, and the very nature of impacts.

The impact would have also eliminated the chance this asteroid might hit the Earth in the future. 2024 YR4 orbits the Sun about every four years. Previous calculations suggested another potentially dangerous fly-by of Earth in 2047, but these numbers are unreliable because the orbit will be changed by the 2032 fly-by in ways that cannot be predicted as yet.

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OHB Italia wins $96 million contract to build Ramses probe to visit the asteroid Apophis

9:39 am

Apophis' path past the Earth in 2029
A cartoon (not to scale) showing Apophis’s
path in 2029

The European Space Agency (ESA) yesterday announced that it has awarded the aerospace company OHB Italia a $96 million contract to build Ramses probe to rendezvous with the potentially dangerous asteroid Apophis when it makes its next close fly-by of Earth in 2029.

This contract is in addition to the $75 million development contract awarded OHB Italia in 2024. According to the company’s press release here:

The launch is scheduled for April 2028, with a rendezvous with Apophis planned for February 2029, approximately two months before its close approach to Earth. The spacecraft will accompany the asteroid until August 2029, in order to observe in detail how Earth’s tidal forces modify its shape, rotation, orbit and surface characteristics.

The initiative also benefits from strong international cooperation. The Japan Aerospace Exploration Agency (JAXA), drawing on its well-established expertise in asteroid science, will contribute by providing launch service onboard an H3 rocket, the spacecraft’s solar arrays and a Thermal Infrared Imager, further reinforcing the project’s global dimension.

In addition, two cubesats will be launched with Ramses and deployed once the spacecraft reaches Apophis.

This schedule is very tight, which places great pressure on OHB, especially because European space projects are traditionally built slowly after years of planning. ESA almost never does things fast like this.

At the moment, Osiris-Apex (formerly Osiris-Rex) is the only spacecraft that is on its way to Apophis.

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A galaxy’s swirling dust lanes

12:07 pm

A galaxy with swirling dust lanes
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken by the Hubble Space Telescope as part of follow-up observations of a now faded supernovae that occurred there two years earlier.

This was on purpose: the aim of the observations was to witness the aftereffects of the supernova and examine its surroundings, which can only be done once the intense light of the explosion is gone.

The galaxy itself, NGC 7722, is 187 million light years away, and is unusual in itself.

A “lenticular”, meaning “lens-shaped”, galaxy is a type that sits in between the more familiar spiral galaxies and elliptical galaxies. It is also less common than these — partly because when a galaxy has an ambiguous appearance, it can be hard to determine if it is actually a spiral, actually an elliptical galaxy, or something in between. Many of the known lenticular galaxies sport features of both spiral and elliptical galaxies. In this case, NGC 7722 lacks the defined arms of a spiral galaxy, while it has an extended, glowing halo and a bright bulge in the center similar to an elliptical galaxy. Unlike elliptical galaxies, it has a visible disc — concentric rings swirl around its bright nucleus. Its most prominent feature, however, is undoubtedly the long lanes of dark red dust coiling around the outer disc and halo.

The streak in the lower left is a very distant background galaxy, seen on edge.

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Comet K1/Atlas has broken apart, not interstellar Comet 3I/Atlas

10:37 am

the end of Comet K1/Atlas

CORRECTION: The image to the right is not that of interstellar Comet 3I/Atlas, as I reported earlier today. I misread the Gemini Telescope release. This is comet K1/Atlas, another comet from our own solar system that made its close approach to the Sun in October, when it broke up.

The the latest image from the Gemini North Telescope in Hawaii shows at least four sections slowly drifting apart.

The picture to the right, cropped to post here, was taken on December 6, 2025. Gemini’s previous image, taken in November 11th, shows about the same number of objects, but clustered much more closely together.

It appears that as the comet made its closest approach, the stress was too great. This is not surprising, as it happens to many comets that get too close to the Sun.

Sorry for the error and hat tip to reader Tom Laskowski for letting me know. I need to look at the names of comets named after the ATLAS telescope, as they are very similar and most are NOT interstellar comet 3I/Atlas.

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Billionaire to fund construction of an orbiting optical telescope larger than Hubble

10:42 am

Lazuli
Figure 1 from the proposal paper [pdf].

Schmidt Sciences, a foundation created by one of Google’s founders, announced yesterday it is financing the construction of four new research telescopes, one of which will be an orbiting optical telescope with a mirror 3.1 meters in diameter, larger than the 2.4 meter primary mirror on the Hubble Space Telescope.

Today at a meeting of the American Astronomical Society, Schmidt Sciences, a foundation backed by billionaires Eric and Wendy Schmidt, announced one of the largest ever private investments in astronomy: funding for an orbiting observatory larger than NASA’s Hubble Space Telescope, along with funds to build three novel ground-based observatories. The project aims to have all four components up and running by the end of the decade.

“We’re providing a new set of windows into the universe,” says Stuart Feldman, president of Schmidt Sciences, which will manage the observatory system. Time on the telescopes will be open to scientists worldwide, and data harvested by them will be available in linked databases. Schmidt Sciences declined to say how much it is investing but Feldman says the space telescope, called Lazuli, alone will cost hundreds of millions of dollars.

Eric Schmidt was once CEO of Google, and in recent years has been spending his large fortune (estimated to exceed $50 billion) on space ventures. For example, in March 2025 he acquired control of the rocket startup Relativity.

While the three new ground-based telescopes will do important work, the Lazuli space telescope is by far the most important, not only scientifically but culturally. » Read more

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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.

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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.

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New data from VLT uncovers numerous debris disks around stars

9:01 am

A sampling of debris disks
Click for original

Using a new instrument on the Very Large Telescope (VLT) in Chile, astronomers have compiled a catalog of 51 potential exoplanet solar systems, all with intriguing debris disks surround the stars with features suggesting the existence of asteroids and comets.

The image to the right shows a sampling of those systems. From the press release:

“To obtain this collection, we processed data from observations of 161 nearby young stars whose infrared emission strongly indicates the presence of a debris disk,” says Natalia Engler (ETH Zurich), the lead author of the study. “The resulting images show 51 debris disks with a variety of properties — some smaller, some larger, some seen from the side and some nearly face-on – and a considerable diversity of disk structures. Four of the disks had never been imaged before.”

Comparisons within a larger sample are crucial for discovering the systematics behind object properties. In this case, an analysis of the 51 debris disks and their stars confirmed several systematic trends: When a young star is more massive, its debris disk tends to have more mass as well. The same is true for debris disks where the majority of the material is located at a greater distance from the central star.

Arguably the most interesting feature of the SPHERE debris disks are the structures within the disks themselves. In many of the images, disks have a concentric ring- or band-like structure, with disk material predominantly found at specific distances from the central star. The distribution of small bodies in our own solar system has a similar structure, with small bodies concentrated in the asteroid belt (asteroids) and the Kuiper belt (comets).

The data from various telescopes both on the ground and in space is increasingly telling us that our solar system is not unique, and that the galaxy is filled with millions of similar systems, all in different states of formation. This hypothesis is further strengthened by the appearance of interstellar comet 3I/Atlas, which despite coming from outside our solar system is remarkably similar to the comets formed here.

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Three new papers find sugars, “gum,” and lots of stardust in the samples brought back from the asteroid Bennu

10:24 am

Bennu
The asteroid Bennu

Three new papers published this week have found that the samples brought back by OSIRIS-REx from the asteroid Bennu contained some unexpected or unusual materials, including sugars that are important for biology, a gumlike material never seen before, and a much higher amount of stardust than expected.

The papers can be read here, here, and here.

As the press release notes, describing the sugar discovery:

The five-carbon sugar ribose and, for the first time in an extraterrestrial sample, six-carbon glucose were found. Although these sugars are not evidence of life, their detection, along with previous detections of amino acids, nucleobases, and carboxylic acids in Bennu samples, show building blocks of biological molecules were widespread throughout the solar system.

The stardust results found six-times the abundance previously found in other samples.

As for the “gum”, this was possibly the strangest discovery of all, coming from the solar system’s earliest time period.
» Read more

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NASA releases images during Osiris-Apex’s fly-by of Earth in late September

9:42 am

Earth as seen by Osiris-Apex
Click for original image.

NASA today released photos taken by the asteroid probe Osiris-Apex (formerly Osiris-Rex) as it swung past the Earth on September 23, 2025 at a distance 2,136 miles, on its way to the asteroid Apophis.

The picture to the right, cropped, reduced, and sharpened to post here, was one of about 424 images taken by the spacecraft during the fly-by. From those, scientists compiled a movie, which you can view here. As this picture shows, South America was in view on the right side of the Earth.

Osiris-Apex, which had already completed its prime mission by returning samples from the asteroid Bennu, is scheduled to arrive at Apophis shortly after that asteroid’s close fly-by of the Earth on April 13, 2029. The Trump administration had threatened to shut it down for budget reasons, but Congress restored those funds in ending the government shut down.

At that time Apophis will zip past only 20,000 miles from Earth. There will be no chance of collision. Nor is there much chance Apophis will hit the Earth in the next two centuries. Its orbit however makes it a potentially dangerous asteroid, and that 2029 fly-by could change these calculations.

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The second known asteroid discovered orbiting closer to the Sun than Venus

8:56 am

Using ground-based telescopes scanning the morning and evening sky, an astronomer has discovered only the second known asteroid circling the Sun within the orbit of Venus.

The manner of the discovery itself, by Scott Sheppard of the Carnegie Institution, also illustrated our modern world.

He first observed it using the Cerro Tololo Dark Energy Camera the night before leaving on a hiking trip. Because the object was moving fast, he knew it must be very close to the Sun, so he’d need to image it again and soon to confirm its orbit before it became lost in the Sun’s glare.

“I had to schedule new observations to re-observe the object while deep in the forest of Pennsylvania,” he says. “It is just amazing that even camp sites today have good Wi-Fi access — that allowed me to download the new second observations of this asteroid and determine its unique orbit that is interior to Venus.”

Astronomers have found so few asteroids close to the Sun because the Sun’s glare makes observations difficult. Some scientists like to speculate to the press that there could be a large unknown population, with some posing a threat to Earth. The computer predictions however say the population is small, because the push of the Sun’s light and radiation should easily shift their orbits outward or make them unstable.

The two asteroids so far found confirm these models in a counter-intuitive way. The new asteroid is estimated to be a little less than a half mile across, while the previously discovered asteroid is thought to have a diameter of more than a mile. Their larger size makes it harder for the Sun’s light and radiation to shift their orbit.

In other words, this inner population of asteroids is likely to be low in number, but made up of larger objects.

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New study claims the giant impact that created the Moon’s South Pole-Aitken Basin was oblique, from the south

9:14 am

South Pole-Aitken Basin
Click for original. Blue indicates the basin, red
the “thorium-rich and iron-rich ejecta deposit”

While previous work had suggested the giant bolide that had created the Moon’s South Pole-Aitken Basin came in from the north, a new study now proposes that the impact was instead oblique from the south. From the paper’s abstract:

The ancient South Pole–Aitken impact basin provides a key data point for our understanding of the evolution of the Moon, as it formed during the earliest pre-Nectarian epoch of lunar history, excavated more deeply than any other known impact basin, and is found on the lunar far side, about which less is known than the well-explored near side. Here we show that the tapering of the basin outline and the more gradual topographic and crustal thickness transition towards the south support a southward impact trajectory, opposite of that commonly assumed. A broad thorium-rich and iron-rich ejecta deposit southwest of the basin is consistent with partial excavation of late-stage magma ocean liquids.

These observations indicate that thorium-rich magma ocean liquids persisted only beneath the southwestern half of the basin at the time of impact, matching predictions for the transition from a global magma ocean to a local enrichment of potassium, rare-earth elements and phosphorus (KREEP) in the near-side Procellarum KREEP Terrane.

In other words, when this impact occurred, part of the impact site in the south was still a magma ocean.

This result, if confirmed, has research implications for the missions targeting the Moon’s south pole. It suggests the geology will have that KREEP materials readily available, which will provide important information about the Moon’s early geological history.

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Australian satellite startup to fly an instrument on private mission to Apophis

8:59 am

In March 2024 the orbital tug startup Exlab’s announced that it will use its orbital tug to deliver three cubesats to the asteroid Apophis when that object makes its next close fly-by of the Earth on April 13, 2029.

The California-based Exlab has now signed its first customer for that mission. An Australian satellite startup, Fleet Space Technologies, has agreed to fly an instrument on this private commercial mission.

Under the ApophisExL mission, Fleet will provide geophysical sensing technologies for ExLabs’ mothership to collect targeted data and characterize the asteroid. The datasets should enable new avenues for data sharing and commercial use, set criteria for prioritizing asteroids for prospecting and feed critical intelligence into planetary‑defence planning.

Fleet already has a contract to fly another instrument, a seismometer, on Firefly’s second Blue Ghost lander mission to the Moon. It has also developed and flown satellite instruments used to detect minerals on Earth.

Both companies are clearly aiming to enhance their brand name with this mission, set to launch in 2028.

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Astronomers refine the spin and size of Hayabusa-2’s next target asteroid

10:15 am

Using a number of ground-based telescopes, astronomers have determined that asteroid 1998 KY26, which Japan’s Hayabusa-2 probe will visit in 2031, spins much faster and is much smaller than previously estimated.

The new observations, combined with previous radar data, have revealed that the asteroid, 1998 KY26, is just 11 meters wide. It is also spinning about twice as fast as previously thought: “One day on this asteroid lasts only five minutes!” he says. Previous data indicated that the asteroid was around 30 meters in diameter and completed a rotation in approximately 10 minutes. The smaller size and faster rotation will make the spacecraft’s touchdown maneuver more difficult to perform than anticipated.

The observations also found that 1998 KY26 is bright, suggesting it is a solid object, not a rubble pile. Its fast rotation adds weight to this conclusion.

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Lucy scientists name the features on asteroid Donaldjohanson

10:16 am

The named features on Donaldjohanson
Click for original.

The science team for the asteroid probe Lucy have now released their names for the features they discovered on the main belt asteroid Donaldjohanson when the spacecraft flew past in April 2025.

The smaller lobe is called Afar Lobus, after the Ethiopian region where Lucy and other hominin fossils were found. The larger lobe is named Olduvai Lobus, after the Tanzanian river gorge that has also yielded many important hominin discoveries.

The asteroid’s neck, Windover Collum, which joins those two lobes, is named after the Windover Archeological Site near Cape Canaveral Space Force Station in Florida — where NASA’s Lucy mission launched in 2021. Human remains and artifacts recovered from that site revolutionized our understanding of the people who lived in Florida around 7,300 years ago.

Two smooth areas on the asteroid’s neck are named Hadar Regio, marking the specific site of Johanson’s discovery of the Lucy fossil, and Minatogawa Regio, after the location where the oldest known hominins in Japan were found. Select boulders and craters on Donaldjohanson are named after notable fossils ranging from pre-Homo sapiens hominins to ancient modern humans.

These names were “approved” by the International Astronautical Union (IAU), which claims the authority over the naming of every rock, boulder, pebble in space. The truth is, however, that future spacefarers are going to accept these names no matter what the IAU had said, simply because these scientists did the first exploration of this asteroid. They get to choose, not the IAU.

The spacecraft is now on its long coast out of the main belt and on to the orbit of Jupiter, where it will make fly-bys of ten different asteroids.

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Radar images reveal near Earth asteroid to be a contact binary

12:06 pm

Peanut shaped asteroid
Click for original image.

Just after asteroid 1997 QK1 made its first really close pass of the Earth on August 20, 2025, scientists used the Goldstone radio antenna take 28 high resolution images and discovered that the asteriod is peanut shaped, meaning that it is a contact binary of two objects that have fused together.

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

The asteroid is about 660 feet (200 meters) long and completes one rotation every 4.8 hours. It passed closest to our planet on the day before these observations were made at a distance of about 1.9 million miles (3 million kilometers), or within eight times the distance between Earth and the Moon. The 2025 flyby is the closest that 1997 QK1 has approached to Earth in more than 350 years. Prior to the recent Goldstone observations, very little was known about the asteroid.

These observations resolve surface features down to a resolution of about 25 feet (7.5 meters) and reveal that the object has two rounded lobes that are connected, with one lobe twice the size of the other. Both lobes appear to have concavities that are tens of meters deep.

Though this asteroid is classified as potentially dangerous, calculations of its orbit show it poses no threat for the “foreseeable future.”

That it is a contact binary reinforces the present theory that about 15% of all larger asteroids belong to this class.

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Meteorite that crashed through roof of home in Georgia dated to beginning of solar system

11:40 am

A meteorite that crashed through the roof of a home in Georgia in June 2025 has now been dated to have formed 4.56 billion years ago, to a time when the solar system was just beginning to form.

[The University of Georgia] received 23 grams of the 50 recovered from the piece that penetrated the house. Using optical and electron microscopy to analyze the fragments, Harris says he believes the meteorite to be a Low Metal (L) ordinary Chondrite. That classification means he expects the meteorite to have formed 4.56 billion years ago in the presence of oxygen — older than the Earth itself.

“It belongs to a group of asteroids in the main asteroid belt between Mars and Jupiter that we now think we can tie to a breakup of a much larger asteroid about 470 million years ago,” Harris said. “But in that breakup, some pieces get into Earth-crossing orbits, and if given long enough, their orbit around the sun and Earth’s orbit around the sun end up being at the same place, at the same moment in time.”

There has been a lot of unjustified hype in the mainstream press about this story, mostly about the age of the meteorite. The fact is that this age for a meteorite is simply not a surprise, that almost all chondrite meteorites found are of comparable age, coming from the beginnings of the solar system.

The most unusual part of the story is that the impact occurred through a person’s house. Such events are exceedingly rare. That it happened however was actually fortuitous, in that, first, no one was hurt, and second, it allowed the meteorite to be quickly recovered and analyzed.

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Psyche snaps picture of Earth-Moon system

9:42 am

Earth and Moon, as seen by Psyche
Click for original image.

In a successful test of its cameras and pointing capabilities, the science team operating the probe Psyche — on its way to the asteroid Psyche — were able to snap a picture of Earth-Moon system from about 180 million miles away.

On July 20 and July 23, the spacecraft’s twin cameras captured multiple long-exposure (up to 10-second) pictures of the two bodies, which appear as dots sparkling with reflected sunlight amid a starfield in the constellation Aries.

One of those pictures is shown to the right. The scientists had previously taken similar calibration images of Jupiter and Mars.

To determine whether the imager’s performance is changing, scientists also compare data from the different tests. That way, when the spacecraft slips into orbit around Psyche, scientists can be sure that the instrument behaves as expected. “After this, we may look at Saturn or Vesta to help us continue to test the imagers,” said Jim Bell, the Psyche imager instrument lead at Arizona State University in Tempe. “We’re sort of collecting solar system ‘trading cards’ from these different bodies and running them through our calibration pipeline to make sure we’re getting the right answers.”

The spacecraft is scheduled to arrive at the metal asteroid Psyche in 2029, and will then spend at least two years flying in formation with it.

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Scientists link near Earth asteroids Bennu and Ryugu to much larger main belt asteroid

9:29 am

Ryugu and Bennu

Scientists comparing the spectroscopy of samples returned from the near Earth asteroids Bennu and Ryugu have found they closely resemble the much larger main belt asteroid Polana, suggesting all three formed at the same time and place.

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

The study compared spectroscopy data from Polana with spacecraft and laboratory data from Bennu and Ryugu samples, discovering similarities in their near-infrared spectrum sufficient to support the theory that they originate from the same parent asteroid. “Very early in the formation of the solar system, we believe large asteroids collided and broke into pieces to form an ‘asteroid family’ with Polana as the largest remaining body,” said SwRI’s Dr. Anicia Arredondo, lead author of the study. “Theories suggest that remnants of that collision not only created Polana, but also Bennu and Ryugu as well.”

While the similarities are great, the paper notes there are differences, possibly from “space weathering, particle size, surface texture, or different compositions.” The scientists believe the differences were caused by the asteroids’ different environments, with the 33-mile-wide and much older Polana in the asteroid belt beyond Mars, and Ryugu and Bennu, both less than a mile wide, orbiting the Sun inside Mars.

It is also possible the asteroids have little to do with each other, and the similar spectroscopy only informs us of some of the more common components of the early solar system.

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Radar images of near Earth asteroid as it zipped past the Earth

9:11 am

Radar images of near Earth asteroid
Click for original. Go here for movie made from these images.

Using the Goldstone radar antenna in California, astronomers have produced a series of 41 radar images of the near Earth asteroid 2025 OW as it made a close pass of the Earth on July 28, 2025.

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

The asteroid safely passed at about 400,000 miles (640,000 kilometers), or 1.6 times the distance from Earth to the Moon.

The asteroid was discovered on July 4, 2025, by the NASA-funded Pan-STARRS2 survey telescope on Haleakala in Maui, Hawaii. These Goldstone observations suggest that 2025 OW is about 200 feet (60 meters) wide and has an irregular shape. The observations also indicate that it is rapidly spinning, completing one rotation every 1½ to 3 minutes, making it one of the fastest-spinning near-Earth asteroids that the powerful radar system has observed. The observations resolve surface features down to 12 feet (3.75 meters) wide.

The asteroid’s fast rotation suggests it is a solid object, structurally strong, rather than a rubble pile held together loosely by gravity. It would thus be very damaging if it should ever hit the Earth.

No worries however. The refined orbital data says this asteroid will not come this close again in the foreseeable future.

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Hera photographs two main belt asteroids on its way to Didymos/Dimorphos

10:12 am

Asteroid Otero as seen by Hera
Click for original image.

The science team for the European Space Agency’s Hera asteroid probe, on its way to the binary asteroid Didymos/Dimorphos in late 2026, has successfully taken images of two different main belt asteroids, demonstrating once again that its camera and pointing capabilities are operating as expected.

The image to the right, cropped, reduced, and enhanced, shows all the observations of Otero, the first asteroid observed, as it moved upward in the field of view. The result was that vertical line of dots.

On 11 May 2025, as Hera cruised through the main asteroid belt beyond the orbit of Mars, the spacecraft turned its attention toward Otero, a rare A-type asteroid discovered almost 100 years ago.

From a distance of approximately three million kilometres, Otero appeared as a moving point of light – easily mistaken for a star if not for its subtle motion across the background sky. Hera captured images of Otero using its Asteroid Framing Camera – a navigational and scientific instrument that will be used to guide the spacecraft during its approach to Didymos next year.

The second observation of asteroid Kellyday was even less spectacular visually, but because that asteroid was forty times fainter than Otero, the observation was more challenging, and thus its success more significant.

Hera will arrive at the Didymos/Dimorphos binary asteroid in 2026, where it will make close-up observations of the changes the asteroids have undergone following Dart’s impact of Dimorphos in 2022. Subsequent ground- and space-based observations have been extensive and on-going, but the close-up view will be ground-breaking.

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First Hubble images of interstellar comet 3I/Atlas released

5:03 pm

Comet 3I/Atlas, taken by Hubble
Click for original.

An undergraduate student has just released the first pictures taken by the Hubble Space Telescope of the interstellar object 3I/Atlas, confirming that it is a comet as indicated by the earlier image taken by the Gemini North telescope.

One of those images, taken only hours ago, is the inset on the map showing the comet’s route through the solar system to the right. The streaks on the image are either stars or cosmic rays. Though this image is of significantly lower quality than the Gemini North picture, it once again shows both the comet’s nucleus and developing coma.

A preprint [pdf] of a new research paper based on data from both telescopes further confirms this conclusion:

[T]hese results suggest that 3I/ATLAS hosts a coma containing large water ice grains, and that its dust continuum is stable over at least week-long timescales. The spectral characteristics further distinguish 3I from known ultrared trans-Neptunian objects and align it more closely with active Jupiter-family comets.

The last conclusion is very significant. Though the path and speed of this interstellar object says it must come from beyond the solar system, its cometary make-up more resembles comets that reside in the inner solar system. These facts strongly imply that there is at least one other solar systems not very different from our own.

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A Martian meteorite discovered in Africa is up for auction

9:10 am

A Martian rock that fell as a meteorite in Africa and was discovered by a professional meteorite hunter and is the largest such Mars rock found so far is about to go up for sale by auction.

NWA16788 is the largest known piece of Mars on Earth, and its internal composition suggests it was disgorged from the surface of the Red Planet by an asteroid impact so extreme that it turned some of the meteorite’s minerals into glass.

Looking certain to blow past its lower estimate of US$2.0 million, this monumental 54-lb (24.67-kg) lump of Mars has already been bid to $1,920,000 (inc Buyer’s Premium) 12 days before the on-line hammer falls, and even its $4-milllion upper estimate doesn’t look safe with this much interest so early in an online auction.

The expected high price is partly because of the meteorite’s size, and partly because almost such meteorites are found by scientists working for NASA, and are thus never made available for sale. To have one available for purchase is rare indeed.

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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.

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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.

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Scientists discover unexpected mineral in Ryugu asteroid sample

1:21 pm

Scientists analyzing the samples brought back from the rubble pile asteroid Ryugu by Japan’s Hayabusa-2 spacecraft have now discovered an unexpected mineral, dubbed djerfisherite, that the formation theories of the asteroid say should not be there.

“Djerfisherite is a mineral that typically forms in very reduced environments, like those found in enstatite chondrites, and has never been reported in CI chondrites or other Ryugu grains,” says first and corresponding author Masaaki Miyahara, associate professor at the Graduate School of Advanced Science and Engineering, Hiroshima University. “Its occurrence is like finding a tropical seed in Arctic ice—indicating either an unexpected local environment or long-distance transport in the early solar system.”

At present the scientists propose two hypotheses for explaining the mineral. Either it came from another asteroid as Ryugu was congealing, or it formed in Ryugu when conditions raised its temperature above 350 degrees Celsius. The researchers now favor the latter theory, even though the generally accepted histories of Ryugu’s formation never included such conditions.

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Scientists increase the odds asteroid 2024 YR4 will impact the Moon in 2032

9:10 am

Asteroid 2024 YR4 in 2032
Click for original image.

Using additional data obtained by the Webb Space Telescope, scientists have now refined the orbit of potentially dangerous asteroid 2024 YR4 and confirmed that while it will almost certainly not hit the Earth in 2032, the odds of it impacting the Moon have increased.

With the additional data, experts from NASA’s Center for Near-Earth Object Studies at the agency’s Jet Propulsion Laboratory in Southern California further refined the asteroid’s orbit. The Webb data improved our knowledge of where the asteroid will be on Dec. 22, 2032, by nearly 20%. As a result, the asteroid’s probability of impacting the Moon has slightly increased from 3.8% to 4.3%. In the small chance that the asteroid were to impact, it would not alter the Moon’s orbit.

The yellow line in the image to the right shows the present range of positions the asteroid could be in as it passes the Moon on that date. It is expected this range will be narrowed further when the asteroid flies past the Earth harmlessly in 2028.

If the asteroid should hit the Moon, the impact will provide scientists a great opportunity to learn more about asteroids and the Moon. If it should miss, it will then be essential to recalculate its orbit to see what will happen on later near approaches, whether the fly-by increased or decreased the chances of a later Earth impact.

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China launches its first asteroid sample return mission

12:28 pm

China today successfully launched Tianwen-2, its first mission attempting to return a sample from a near Earth asteroid, its Long March 3B rocket lifting off from its Xichang spaceport in southwest China.

Video of the launch can be found here. 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.

Some data suggests Kamo’oalewa is possibly a fragment from the Moon, but that is not confirmed.

After a year studying Kamo-oalewa, Tienwen-2 will then return past the Earth where it will release its sample capsule. The spacecraft will then travel to Comet 311P/PANSTARRS, reaching it in 2034. This comet is puzzling because it has an asteroid-like orbit but exhibits activity similar to a comet.

As for the launch, there is no word where the Long March 3B’s lower stages and four strap-on boosters, all using very toxic hypergolic fuels, crashed inside China. It should be noted that the video I link to above was taken by an ordinary citizen watching from a hill nearby, bringing with him a group of children as well. Considering the nature of the rocket’s fuel (which can dissolve your skin if it touches you), China’s attitude is remarkably sanguine to not only drop these stages on its people, but to allow tourists to get so close to launches.

The leaders in the 2025 launch race:

65 SpaceX
31 China (with one more launch scheduled later today)
6 Rocket Lab (with one launch scheduled for today SCRUBBED)
6 Russia

SpaceX now leads the rest of the world in successful launches, 65 to 50.

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Engineers pinpoint and bypass fuel line problem on Psyche

9:00 am

Psyche's flight path to the asteroid Psyche
Psyche’s flight path to the asteroid Psyche.
Click for original image.

In troubleshooting a significant drop in pressure in the xenon gas fuel lines to the ion engines of the Psyche asteroid probe, engineers have now pinpointed the problem to a failed valve and have switched to a back-up fuel line.

Powered by two large solar arrays, Psyche’s thrusters ionize and expel xenon gas to gently propel the spacecraft, which gradually picks up speed during its journey. The team paused the four electric thrusters in early April to investigate an unexpected drop in pressure. They determined that a mechanical issue in one of the valves, which open and close to manage the flow of propellant, caused the decrease. Through extensive testing and diagnostic work, the team concluded that a part inside one of the valves is no longer functioning as expected and is obstructing the flow of xenon to the thrusters.

Now that the swap to the backup fuel line is completed, engineers will command the spacecraft’s thrusters to resume firing by mid-June.

This issue had to be resolved before that scheduled firing in June or else Psyche would have fallen off its course to reach the metal asteroid Psyche by August 2029.

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Astronomers discover another object in an orbit so extreme it reaches the outskirts of the theorized Oort Cloud

12:45 pm

Orbits of known Trans-Neptunian Objects

Astronomers analyzing a dark energy survey by a ground-based telescope have discovered what might be another dwarf planet orbiting the Sun, but doing so in an orbit so extreme that it reaches the outskirts of the theorized Oort Cloud more than 151 billion miles out.

This object, dubbed, 2017 OF201, was found in 19 different observations from 2011 to 2018, allowing the scientists to determine its orbit. The map to the right is figure 2 from their paper [pdf], with the calculated orbit of 2017 OF201 indicated in red. As you can see, this new object — presently estimated to be about 450 miles in diameter — is not the first such object found in the outer solar system with such a wide eccentric orbit. However, the object also travels in a very different region than all those other similar discoveries, suggesting strongly that there are a lot more such objects in the distant outer solar system.

Its existence also contradicts a model that proposed the existence of a larger Planet X. That theory posited that this as-yet undetected Planet X was clustering the orbits of those other distant Trans-Neptunian objects shown on the map.

As shown in Figure 2, the longitude of perihelion of 2017 OF201 lies outside the clustering region near π ≈ 60◦ observed among other extreme TNOs [Trans-Nepturnian Objects]. This distinction raises the question of whether 2017 OF201 is dynamically consistent with the Planet X hypothesis, which suggests that a distant massive planet shepherds TNOs into clustered orbital configurations. Siraj et al. (2025) computed the most probable orbit for a hypothetical Planet X by requiring that it both reproduces the observed clustering in the orbits of extreme TNOs.

…These results suggest that the existence of 2017 OF201 may be difficult to reconcile with this particular instantiation of the Planet X hypothesis. While not definitive, 2017 OF201 provides an additional constraint that complements other challenges to the Planet X scenario, such as observational selection effects and the statistical robustness of the observed clustering.

Planet X might exist, but if so it is likely simple one of many such objects in the outer solar system. It is also likely to be comparable in size to these other objects, which range from Pluto-sized and smaller, making it less unique and less distinct.

In other words, our solar system has almost certainly far more planets than nine (including Pluto).

Hat tip to BtB’s stringer Jay.

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