Tag: asteroids

NASA sets new launch date for Psyche asteroid mission

9:01 am

NASA yesterday announced that the delayed Psyche mission, to the asteroid Psyche, now has a new launch date of October 10, 2023, with a planned arrival in 2029.

The spacecraft missed its original launch date in 2022 because of the late delivery of its flight software combined with problems with the equipment needed to test that software.

The new launch date, though only one year later than planned, will cause the spacecraft to arrive two years late because of orbital mechanics.

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InSight detects and dates large impact on Mars

11:14 am

InSight's Christmas Eve impact
Click for full image.

Using the data from InSight’s seismometer of a 4 magnitude earthquake on Mars on December 24, 2021, scientists were able to use the high resolution camera on Mars Reconnaissance Orbiter (MRO) to find the meteorite impact that produced that quake, the largest detected since spacecraft have been visiting Mars. The picture to the right, cropped and reduced to post here and unveiled at yesterday’s press conference, shows the new crater.

The meteoroid is estimated to have spanned 16 to 39 feet (5 to 12 meters) – small enough that it would have burned up in Earth’s atmosphere, but not in Mars’ thin atmosphere, which is just 1% as dense as our planet’s. The impact, in a region called Amazonis Planitia, blasted a crater roughly 492 feet (150 meters) across and 70 feet (21 meters) deep. Some of the ejecta thrown by the impact flew as far as 23 miles (37 kilometers) away.

With images and seismic data documenting the event, this is believed to be one of the largest craters ever witnessed forming any place in the solar system.

This is not the first such impact identified from InSight seismic data, but it is the largest. The white streaks surrounding the crater are thought to be near-surface ice ejected at impact.

The overview map below provides further context, as well as showing us the proximity of this impact to the proposed Starship landing sites on Mars.
» Read more

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Lucy’s view of the Earth-Moon system during its October fly-by

8:35 am

The Earth and Moon system, as seen by Lucy
Click for original image.

Lucy's planned route
Lucy’s planned route to explore the Trojan asteroids

In the days prior to its October 16, 2022 fly-by of the Earth, the Lucy asteroid probe took several calibration images of the Earth and the Moon. The photo above, cropped, reduced, and enhanced to post here, shows both the Earth and the Moon together. From the caption:

On October 13, 2022, NASA’s Lucy spacecraft captured this image of the Earth and the Moon from a distance of 890,000 miles (1.4 million km). The image was taken as part of an instrument calibration sequence as the spacecraft approached Earth for its first of three Earth gravity assists. These Earth flybys provide Lucy with the speed required to reach the Trojan asteroids — small bodies that orbit the Sun at the same distance as Jupiter.

In the original, the Moon is so dim, compared to the Earth, that it was hard to find in the picture. I therefore brightened it considerably more than the Earth to make it easily seen above.

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Hubble spots double tail of debris from DART impact of Dimorphus

11:28 am

Dimorphus double tail
Click for original image.

A series of images taken by the Hubble Space Telescope of the ejecta released when DART crashed into the small 525-foot-wide asteroid Dimorphus has found that debris forming a double tail trailing away from the Sun.

The picture to the right, cropped, reduced, and enhanced to post here, was taken on October 11, 2022 by Hubble, and shows those two tails as close parallel debris trails.

Repeated observations from Hubble over the last several weeks have allowed scientists to present a more complete picture of how the system’s debris cloud has evolved over time. The observations show that the ejected material, or “ejecta,” has expanded and faded in brightness as time went on after impact, largely as expected. The twin tail is an unexpected development, although similar behavior is commonly seen in comets and active asteroids. The Hubble observations provide the best-quality image of the double-tail to date.

Following impact, Hubble made 18 observations of the system. Imagery indicates the second tail formed between 2-8 October 2022.

Though observations by telescope will continue for the years to follow, the real punchline to this event will be when the European probe Hera rendezvouses with the Didymous-Dimorphus pair in 2026 to perform several years of very close observations.

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Twelve years of data from WISE

10:43 am

The Wide Field Infrared Survey Explorer (WISE) was launched in 2009 with an intended mission of two years, during which it would map the sky looking for asteroids. In 2011 NASA extended the mission, renaming the telescope for inexplicable reasons to NEOWISE (adding “Near-Earth Object” to the beginning).

In the more than a decade since, the telescope has been able to get eighteen repeated scans of the entire sky, allowing scientists to track many changes in a variety of stellar objects over time.

Yesterday NASA issued a press release celebrating this long achievement.

Every six months, NASA’s Near-Earth Object Wide Field Infrared Survey Explorer, or NEOWISE, spacecraft completes one trip halfway around the Sun, taking images in all directions. Stitched together, those images form an “all-sky” map showing the location and brightness of hundreds of millions of objects. Using 18 all-sky maps produced by the spacecraft (with the 19th and 20th to be released in March 2023), scientists have created what is essentially a time-lapse movie of the sky, revealing changes that span a decade.

There is a bit of hype in this claim. The data isn’t really useful when looked at across the entire sky. One has to zoom into particular objects to see them evolve over time. Also, many of these changes, such as with variable stars, are well known and tracked by many other telescopes.

Nonetheless, this infrared database is very valuable. It can be used for example by astronomers to identify objects that should be viewed with high resolution in the infrared, by Webb.

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OSIRIS-REx does mid-course correction

8:36 am

To better refine its path back to Earth in order to properly aim its sample return capsule, engineers had OSIRIS-REx do a short successful 30 second engine burn on September 21, 2022.

Nor will this be the only course correction prior to sample return on September 24, 2023 in Utah.

To ensure a safe delivery, “Over the next year, we will gradually adjust the OSIRIS-REx trajectory to target the spacecraft closer to Earth,” said Daniel Wibben, trajectory-and-maneuver design lead with KinetX Inc. “We have to cross Earth’s orbit at the time that Earth will be at that same location.” Wibben works closely with the Lockheed Martin team in Littleton, Colorado, that flies the spacecraft.

Last month’s maneuver was the first time the OSIRIS-REx team changed the spacecraft’s trajectory since it left Bennu on May 10, 2021. Following this course adjustment, OSIRIS-REx would pass about 1,367 miles (2,200 kilometers) from Earth. A series of maneuvers beginning in July 2023 will bring OSIRIS-REx even closer, to 155 miles (250 kilometers) off the surface, close enough to release its sample capsule for a precision landing – via parachute at the Air Force’s Utah Test and Training Range in the Great Salt Lake Desert.

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Lucy to fly past Earth on October 16th

10:13 am

Lucy solar panel graphic
Artist’s impression of solar panel

As part of its planned route to get to the Trojan asteroids in Jupiter’s orbit, the planetary probe Lucy is scheduled to fly only 220 miles above the Earth’s surface on October 16th.

Lucy will be passing the Earth at such a low altitude that the team had to include the effect of atmospheric drag when designing this flyby. Lucy’s large solar arrays increase this effect.

“In the original plan, Lucy was actually going to pass about 30 miles closer to the Earth,” says Rich Burns, Lucy project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “However, when it became clear that we might have to execute this flyby with one of the solar arrays unlatched, we chose to use a bit of our fuel reserves so that the spacecraft passes the Earth at a slightly higher altitude, reducing the disturbance from the atmospheric drag on the spacecraft’s solar arrays.”

That solar array remains unlatched (as shown in the graphic above), but because it is almost completely deployed and is producing about 90% of its intended electricity, engineers have ceased efforts to complete deployment and latching.

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The known near Earth asteroid catalog now tops 30,000

9:35 am

Chart of NEA's discovered over time

The catalog of known near Earth asteroids that have been identified using a number of survey telescopes in space and on the Earth now totals 30,039. As defined at the link:

An asteroid is called a near-Earth asteroid (NEA) when its trajectory brings it within 1.3 Astronomical Units (au) of the Sun. 1 au is the distance between the Sun and Earth, and so NEAs can come within at least 0.3 au, 45 million km, of our planet’s orbit.

Currently, near-Earth asteroids make up about a third of the roughly one million asteroids discovered so far in the Solar System. Most of them reside in the asteroid belt between Jupiter and Mars.

NEAs are also called NEOs (Near Earth Objects). The chart above, produced by the Center for NEO Studies which tracks these objects, shows the number of NEAs discovered over time.

Of the 30,039 now known, about 1,400 have orbits with “a non-zero” chance of hitting the Earth. None however will do so in the next hundred years at least.

Though the pace of discovery is vastly improving — as indicated by the steep rise in the curve in the graph — only when that curve begins to flatten out will we know that we are getting close to having a more-or-less complete survey of these objects.

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DART’s impact shortened Dimorphus’s orbit around Didymos by 32 minutes

5:51 pm

LICIACube Explorer image of DART impact
LICIACube Explorer image just after the DART
impact. Dimorphus is the blob near the top.

After two weeks of analyzing the orbit of Dimorphus around its parent asteroid Didymos, astronomers have determined that the impact of DART on Dimorphus shortened its orbit by 32 minutes.

Prior to DART’s impact, it took Dimorphos 11 hours and 55 minutes to orbit its larger parent asteroid, Didymos. Since DART’s intentional collision with Dimorphos on Sept. 26, astronomers have been using telescopes on Earth to measure how much that time has changed. Now, the investigation team has confirmed the spacecraft’s impact altered Dimorphos’ orbit around Didymos by 32 minutes, shortening the 11 hour and 55-minute orbit to 11 hours and 23 minutes. This measurement has a margin of uncertainty of approximately plus or minus 2 minutes.

Before its encounter, NASA had defined a minimum successful orbit period change of Dimorphos as change of 73 seconds or more. This early data show DART surpassed this minimum benchmark by more than 25 times.

It also appears the ejecta from the impact — much greater than expected — helped propel Dimorphus, a result that I think was also not expected.

Researchers are now shifting to studying the debris and asteroid itself, to better understand what happened as well as the nature of Dimorphus itself. This will also include a European probe dubbed Hera that will launch in 2024 an dvisit both asteroids in 2026.

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New computer simulation of theorized impact that created the Moon

8:56 am

The uncertainty of science: Before I even begin to describe this story, I must emphasize that it is pure science fiction. As much as it is founded on known data, that data is simply not sufficient to tell us exactly how the Moon was created. The data merely points to many hundreds of possibilities, of which the model below is simply one:

Computer programmers using a supercomputer at a United Kingdom university have created a new simulation of the theorized impact of a Mars-sized body to the Earth that some believe created the Moon, and determined it was possible for that impact to have created the Moon quickly, within hours.

You can read the research paper here.

The fun part of this story is to watch the video of this simulation, which I have embedded below. Whether it describes what actually happened is pure speculation, and in fact cannot be confirmed in any way at all.

It is intriguing, nonetheless.
» Read more

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Chang’e-5 samples suggest lunar meteorite impacts took place the same time as big Chicxulub impact

10:23 am

In analyzing lunar samples brought back by China’s Chang’e-5 Moon lander, Australian scientists have found evidence of lunar meteorite impacts that apparently took place the same time as big Chicxulub impact in the Yucatan 66 million years ago, thought by many scientists to have caused the extinction of the dinosaurs.

Their findings suggest that the frequency of meteorite impacts on the Moon may have been mirrored on Earth, and that major impact events on Earth were not stand-alone events and instead were accompanies by a series of smaller impacts. The study has been published in Science Advances.

“We combined a wide range of microscopic analytical techniques, numerical modelling, and geological surveys to determine how these microscopic glass beads from the Moon were formed and when,” says lead author Professor Alexander Nemchin, from the Space Science and Technology Centre (SSTC) in the School of Earth and Planetary Sciences at Curtin University in Perth.

The data suggests two possibilities, neither of which is confirmed. First, the impacts could have occurred because a cluster of large objects hit both Earth and the Moon at the same time. Second, the impacts on the Moon could have been caused by objects thrown up from the Earth when the bigger impact occurred at Chicxulub.

Either way, the data suggests a greater and more complex interaction between events on the Earth and events on the Moon.

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Hubble & Webb make first coordinated observations, tracking DART impact of Dimorphus

9:50 am

Webb and Hubble together look at DART impact of Dimorphus
Click for full image.

For the first time scientists have used both the Hubble Space Telescope and the James Webb Space Telescope to observe the same astronomical event, in this case the impact of the DART spacecraft on the asteroid Dimorphus on September 26, 2022.

The two images to the right show the asteroid several hours after impact. Both telescopes also captured images before the impact as well. From the press release:

Observations from Webb and Hubble together will allow scientists to gain knowledge about the nature of the surface of Dimorphos, how much material was ejected by the collision, and how fast it was ejected. Additionally, Webb and Hubble captured the impact in different wavelengths of light – Webb in infrared and Hubble in visible. Observing the impact across a wide array of wavelengths will reveal the distribution of particle sizes in the expanding dust cloud, helping to determine whether it threw off lots of big chunks or mostly fine dust. Combining this information, along with ground-based telescope observations, will help scientists to understand how effectively a kinetic impact can modify an asteroid’s orbit.

When Webb was first conceived in the late 1990s, it was exactly for this reason, to combine Hubble’s optical vision with Webb’s infrared view. Though more than a decade late, it has finally happened.

It will be months before scientists begin to decipher the data produced by all the telescopes and spacecraft used to observe the DART impact. What we are seeing now are merely hints at what has been learned.

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Watch DART smash into asteroid today

9:27 am

At 7:14 pm (Eastern) the NASA’s Double Asteroid Redirection Test (DART) spacecraft will crash into the small and harmless asteroid Dimorphus to see if such an impact could be used in the future to change the path of another asteroid aimed at Earth.

Dimorphus is 525 feet in diameter, and is a small moon of the larger half-mile-wide asteroid Didymos. Both are presently about 7 million miles away from Earth.

I have embedded the live streams below, one from a DART camera, dubbed DRACO, that will view the asteroid as the spacecraft approaches, and the other from NASA’s official live stream. From the DRACO live stream webpage:
» Read more

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Watching DART impact asteroid on September 26, 2022

9:35 am

A NASA planetary probe, dubbed DART, is on course for a planned impact of the asteroid Dimorphos this coming Monday, September 26, 2022, at 4:14 PM (Pacific).

DART was launched from Vandenberg Space Force Base, CA on November 23, 2021 PST (November 24 EST) headed to the asteroid Didymos and its tiny moon Dimorphos 7 million miles away. The plan is for DART to ram itself into Dimorphos while scientists on Earth measure whether its orbit around Didymos changes.

Dimorphos is about 525 feet in diameter, while Didymos is much larger, about a half mile in width. The goal is to see if this method can be used in the future to adjust an asteroid’s orbit enough to shift it away from hitting the Earth.

The impact will be observed by a camera on DART, as well as an Italian cubesat dubbed LICIACube.

NASA TV will be live streaming the event, and I will embed that live stream here when it goes live. Once DART gets close, its camera will record the asteroid’s approach through impact.

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Samples from Ryugu prove the truly delicate and long-lived nature of the rubble-pile asteroid

9:27 am

Two new studies of samples brought back from the rubble-pile asteroid Ryugu by the Japanese probe Hayabusa-2 have found that the asteroid not only was never heated above 86 degrees Fahrenheit, it also contained dust grains older than the solar system itself.

The evidence from the first study, completed by Japanese scientists, suggested that:

  • 1.Asteroid Ryugu accreted some components that originated in the outer Solar System and contained abundant water and organics. The asteroid then traveled to the inner Solar System.
  • 2.Organics associated with coarse-grained phyllosilicates may serve as one of the potential sources of water and organics to the Earth.

The second study, using samples provided to American scientists, found two tiny dust grains that must have come from the material that existed before the formation of our solar system.

The team detected all the previously known types of presolar grains—including one surprise, a silicate that is easily destroyed by chemical processing that is expected to have occurred on the asteroid’s parent body. It was found in a less-chemically-altered fragment that likely shielded it from such activity.

This is not the first discovery of presolar grains, but their delicate existence in Ryugu confirms the conclusions of the first study, that Ryugu had to have formed in the outer solar system and then migrated inward over eons.

The second study also reviewed the make-up of the sample and concluded that Ryugu appears to most closely match the family of carbonaceous Ivuna-type (CI) chondrites, thought to be among the most primitive asteroids known, of which very few have been studied because of they rarely survive the journey through the Earth’s atmosphere.

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Mapping the break-up and impact of one of the first asteroid’s tracked from space to the ground

11:33 am

Computer simulation of asteroid break-up
Click for full figure.

By analyzing 600 scattered pieces recovered from a 20-foot wide asteroid that broke-up and landed in the Sudan in 2008, scientists have discovered that some surface pieces were able to reach the ground unscathed because they were on the asteroid’s protected aft as it plowed through the atmosphere.

This asteroid was one of the first ever discovered shortly before impact and then tracked as it hit the atmosphere and broke up, the pieces falling as meteorites. The image to the right, figure 4 of the paper, shows the computer simulation of the asteroid’s break-up, based on the data obtained by mapping the location of its pieces on the ground. From the press release:

“Because of the high speed coming in, we found that the asteroid punched a near vacuum wake in the atmosphere,” says Robertson. “The first fragments came from the sides of the asteroid and tended to move into that wake, where they mixed and fell to the ground with low relative speeds.”

While falling to the ground, the smallest meteorites were soon stopped by friction with the atmosphere, falling close to the breakup point, while larger meteorites were harder to stop and fell further downrange. As a result, most recovered meteorites were found along a narrow 1-km wide strip in the asteroid’s path. “The asteroid melted more and more at the front until the surviving part at the back and bottom-back of the asteroid reached a point where it suddenly collapsed and broke into many pieces,” said Robertson. “The bottom-back surviving as long as it did was because of the shape of the asteroid.”

No longer trapped by the shock from the asteroid itself, the shocks from the individual pieces now repulsed them, sending these final fragments flying outwards with much higher relative speed. “The largest meteorites from 2008 TC3 were spread wider than the small ones, which means that they originated from this final collapse,” said Jenniskens. “Based on where they were found, we concluded that these pieces stayed relatively large all the way to the ground.”

The location of the large meteorites on the ground still reflects their location in the back and bottom-back part of the original asteroid.

While there is a certain randomness in how any asteroid breaks up, this data will help scientists better understand the make-up of future meteorites they find. The bigger more widely scattered pieces likely came from the asteroid’s rear surface.

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Lucy science team ends attempt to deploy solar array

9:12 am

Lucy's planned journey
Lucy’s planned mission, the yellow dot indicating approximately
its present position. Click for full image.

The Lucy science team has decided to end further attempts to fully deploy one of the spacecraft’s two solar arrays, leaving it just short of fully deployed.

On seven occasions in May and June, the team commanded the spacecraft to simultaneously run the primary and backup solar array deployment motors. The effort succeeded, pulling in the lanyard, and further opening and tensioning the array.

The mission now estimates that Lucy’s solar array is between 353 degrees and 357 degrees open (out of 360 total degrees for a fully deployed array). While the array is not fully latched, it is under substantially more tension, making it stable enough for the spacecraft to operate as needed for mission operations.

The press release announcing this decision is horribly written. First, it buries this decision to the release’s last three paragraphs so that it can rave about the brilliance of Lucy’s engineers and scientists in solving the overall problem. Second, it never actually states that this is the decision that has been made. It implies it.

Regardless, it appears the engineers are satisfied that the almost fully deployed array will hold its position for the rest of the mission. They have decided that the risk of trying to fully deploy it is greater than the risk of having it slightly open.

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OSIRIS-REx’s sample grab at Bennu in 2020 proved the rubble-pile asteroid has far less cohesion than predicted

10:10 am

The post touchdown crater on Bennu

The OSIRIS-REx science team, using data gathered during the spacecraft’s sample grab at Bennu in 2020, has determined that the rubble-pile asteroid has far less cohesion than predicted, with its rubble behaving less like a solid object and more like the playground ball-pits found in amusement parks.

After analyzing data gathered when NASA’s OSIRIS-REx spacecraft collected a sample from asteroid Bennu in October 2020, scientists have learned something astonishing: The spacecraft would have sunk into Bennu had it not fired its thrusters to back away immediately after it grabbed dust and rock from the asteroid’s surface.

It turns out that the particles making up Bennu’s exterior are so loosely packed and lightly bound to each other that if a person were to step onto Bennu they would feel very little resistance, as if stepping into a pit of plastic balls that are popular play areas for kids.

The image above shows what the touch down crater looked like after the sample grab, taken from the video that was part of the press release. The false colors indicate the depth changes produced by the touch down. The final crater was 26 feet across and more than two feet in depth, far larger than expected. Moreover, the energy from the spacecraft’s thrusters as it lifted off had increased the size of that crater further, by about 40%.

These results about the asteroid’s lack of cohesion match the earlier results studying a different impact crater on Bennu.

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Scientists: Comet 67P/C-G’s make-up matches the rest of the solar system

9:33 am

A detailed review of the archived data from the Rosetta mission that studied Comet 67P/Churyumov-Gerasimenko closely in 2014-2016 now strongly suggests that the comet’s overall make-up closely matches the rest of the solar system.

“It turned out that, on average, [the comet’s] complex organics budget is identical to the soluble part of meteoritic organic matter”, explains [Nora Hänni of the University of Bern] and adds: “Moreover, apart from the relative amount of hydrogen atoms, the molecular budget of [comet 67P/C-G] also strongly resembles the organic material raining down on Saturn from its innermost ring, as detected by the INMS mass spectrometer onboard NASA’s Cassini spacecraft”.

“We do not only find similarities of the organic reservoirs in the Solar System, but many of [comet 67P/C-G]’s organic molecules are also present in molecular clouds, the birthplaces of new stars”, complements Prof. Dr. Susanne Wampfler, astrophysicist at the Center for Space and Habitability (CSH) at the University of Bern and co-author of the publication. “Our findings are consistent with and support the scenario of a shared presolar origin of the different reservoirs of Solar System organics, confirming that comets indeed carry material from the times long before our Solar System emerged.”

These results are not unexpected, but having those expectations confirmed was one of the main scientific goals of the Rosetta mission. Now, almost a decade later, the results are in.

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Lucy solar panel almost completely open

11:19 am

Engineers have now been able to get the one solar panel that did not deploy completely after launch on the Lucy asteroid probe almost completely open.

From May 6 to June 16, NASA’s Lucy mission team carried out a multi-stage effort intended to further deploy the spacecraft’s unlatched solar array. The team commanded the spacecraft to operate the array’s deployment motor for limited periods of time, allowing them to closely monitor the response of the spacecraft. As a result of this effort, the mission succeeded in further deploying the array and now estimates that the solar array is between 353 degrees and 357 degrees open (out of 360 total degrees for a fully deployed array). Additionally, the array is under substantially more tension, giving it significantly more stabilization. The mission team is increasingly confident the solar array will successfully meet the mission’s needs in its current tensioned and stabilized state.

The spacecraft’s orbit is now moving into a position where communications will be limited until October, so further attempts to completely open the array will have to wait until then.

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Psyche will not launch as scheduled

9:06 am

NASA officials yesterday confirmed that because of software issues its asteroid mission Psyche will not launch as scheduled this year.

Due to the late delivery of the spacecraft’s flight software and testing equipment, NASA does not have sufficient time to complete the testing needed ahead of its remaining launch period this year, which ends on Oct. 11. The mission team needs more time to ensure that the software will function properly in flight.

…As the mission team at NASA’s Jet Propulsion Laboratory in Southern California began testing the system, a compatibility issue was discovered with the software’s testbed simulators. In May, NASA shifted the mission’s targeted launch date from Aug. 1 to no earlier than Sept. 20 to accommodate the work needed. The issue with the testbeds has been identified and corrected; however, there is not enough time to complete a full checkout of the software for a launch this year.

NASA management will conduct a review to understand what caused the problem.

As for when Psyche can next launch and reach the asteroid Psyche, the next launch windows in ’23 and ’24 will not arrive at the asteroid until ’29 or ’30 respectively, a flight time that is about two years longer than what the ’22 launch would have been.

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Psyche software issue could prevent launch this year

9:08 am

In a remarkably brief announcement on the Psyche website, the engineering team suggested that the flight software issue that forced a seven week delay in its launch might now prevent a launch this year.

This is the entire announcement:

NASA’s Psyche mission team continues to assess ongoing issues with the spacecraft’s flight software. The team is evaluating its ability to meet a schedule to launch in 2022 – the current launch period is Sept. 20 to Oct. 11. If it is determined that launch in 2022 is not possible, a full range of actions for how to proceed will be considered.

This year’s launch window would have gotten the spacecraft to the asteroid Psyche in 2026. Since this flight path required a fly-by of Mars, it is very unclear when another launch window will be available.

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Lucy gets a bonus asteroid during its tour of the Trojans

9:44 am

Lucy's planned journey
Click for full image.

While doing observations in March of one of the eight asteroids the Lucy asteroid will visit in the two Trojan asteroid regions fore and aft of Jupiter, scientists discovered it had a companion, thus increasing the total asteroids to be seen close-up by Lucy to nine.

One of the Trojan asteroids on Lucy’s tour, named Polymele, has a companion. Scientists discovered an apparent satellite of Polymele during a ground-based occultation observation in March, when Polymele briefly passed in front of a star, temporarily blocking its light from reaching Earth. The occultation observations were intended to help the Lucy science team determine the shape of Polymele, which only appears as a point of light in telescope images.

“We got a really nice projected shape of Polymele, and then we were very surprised to detect an object about 200 kilometers (120 miles) away from Polymele,” Levison said last week in a presentation to NASA’s Small Bodies Advisory Group. “It’s 5 kilometers (3 miles) in diameter, and it’s sitting almost exactly in Polymele’s equatorial plane.”

Lucy’s science team has temporarily named the object Shaun, after “Shaun the Sheep” in the show “Wallace and Gromit.”

The graphic above, from the Lucy science team, shows the spacecraft’s planned journey during its mission.

Engineers continue their attempts to fully open one of Lucy’s two solar arrays. On June 9th they successfully used the array’s deployment motors again for a short burst to further open the array. The plan is to repeat these short bursts with the hope the array will eventually latch into its intended open position.

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Delay in Psyche launch wrecks smallsat asteroid mission

9:18 am

The two month delay in the launch of NASA’s Psyche asteroid mission because of software issues has apparently wrecked a smallsat asteroid mission that was to launch as a secondary payload on the Falcon Heavy rocket.

Janus, a NASA smallsat mission selected in 2019, will launch two identical spacecraft as secondary payloads on the Falcon Heavy rocket whose primary payload is Psyche. After a series of Earth flybys, each Janus spacecraft was to fly by different binary asteroids, designated 1996 FG3 and 1991 VH.

However, the mission’s principal investigator said June 8 that mission plan is no longer possible. Speaking at a meeting of NASA’s Small Bodies Assessment Group (SBAG), Dan Scheeres of the University of Colorado noted that mission plan assumed Psyche launched in August of this year as previously planned. NASA announced May 23 that the mission’s launch had been delayed to no earlier than Sept. 20 to provide more time for testing the spacecraft’s software.

With the revised launch date, he said it’s no longer possible for the spacecraft to perform those Earth flybys with the existing spacecraft design. “Those flybys were essential for setting up our flybys of our target binaries, 1991 VH and 1996 FG3,” he said.

The Janus team are right now scrambling to see if they can find other asteroids the spacecraft can reach, based on the new launch date. Their work however is badly hampered by the uncertainty of that date, which could still change for many reasons.

The heart of the problem, as Scheeres notes, is its status as a secondary payload.

“We have no ability to influence the launch dates or the targeting of the launch vehicle, and that arises from our status as a rideshare,” he said.

The article also describes two other NASA interplanetary smallsat missions that have been badly hindered because of their status as secondary payloads. All three stories strongly suggest that in the future it will make much more sense to put such missions on its own rocket, as the primary payload. This is what NASA did with its CAPSTONE smallsat mission to the Moon, which will launch on a Rocket Lab Electron rocket sometime before the end of the month.

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Amino acids found in asteroid samples brought back from Ryugu

10:01 am

Japanese scientists revealed this week that they have detected more than 20 types of amino acids in the asteroid samples brought back from Ryugu by the probe Hayabusa-2.

Kensei Kobayashi, professor emeritus of astrobiology at Yokohama National University, said the unprecedented discovery of multiple types of amino acids on an extraterrestrial body could even hint at the existence of life outside of Earth. “Proving amino acids exist in the subsurface of asteroids increases the likelihood that the compounds arrived on Earth from space,” he said.

It also means amino acids can likely be found on other planets and natural satellites, hinting that “life could have been born in more places in the universe than previously thought,” Kobayashi added.

Let me emphasize that this is not a discovery of life on Ryugu, only chemistry that is found in life on Earth. Such chemistry however can be found outside of life as well. What this detection suggests however that it is relatively common to produce such complex chemistry in hostile space environments, which increases greatly the possibility of life everywhere in the universe.

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Progress in completing the deployment of one of Lucy’s solar panels

9:45 am

Lucy solar panel graphic
Artist’s impression of solar panel

In the past month engineers for the Lucy asteroid mission have conducted a series of successful short tests to see if they can complete the unfolding of one of the probe’s two large solar panels.

On May 9, the team commanded the spacecraft to operate the array’s deployment motor using both the primary and back-up motor windings simultaneously to generate more torque, i.e. a harder pull. The motor operated as expected, further reeling in the lanyard that pulls the solar array open. After running the motor for a series of short intervals to avoid overheating, the team paused to analyze the results. Data from the spacecraft showed that the deployment was proceeding similarly to engineering ground tests, allowing the team to move forward with the second stage of the attempt. Analysis of the data also suggested that there was still additional lanyard to be retracted. The team sent the same commands again on May 12. Although this series of commands did not latch the solar array fully open, it did advance the deployment enough to increase the tension that stabilizes the arrays as was hoped.

On May 26, the spacecraft was again commanded to deploy the solar array. As in the first two attempts, both motor windings were operated simultaneously for short periods of time to avoid overheating. Afterwards the team again analyzed the data from the event, which again showed that the array was continuing to open. The team repeated the deployment command sequence a fourth time on June 2. While the array still did not latch, the data indicates that it continued to further deploy and stiffen throughout the attempt.

The graphic above illustrates the problem. The engineers will attempt further windings, and still hope the panel will open entirely and latch. If not, the stiffening suggests the panel will still stabilize in this open position, which up to now has been sufficient to produce about 90% of the power predicted and enough to complete the mission.

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South Korea cancels probe to asteroid Apophis

8:57 am

The South Korea government has canceled its proposed unmanned probe to asteroid Apophis that had been designed to reach the asteroid during its ’29 close approach of Earth and fly in formation with it.

The science ministry, which manages state-funded space programs, recently ruled the mission “unfeasible” and decided not to request the $307.7 million budget it initially sought for the mission. … “We’ve decided not to pursue Apophis probe mission because there were various issues making it difficult for the mission to be successful,” Shin Won-sik, a science ministry official, told SpaceNews. “To probe Apophis, we have to launch a spacecraft by 2027 at the latest. But with the rocket and spacecraft-making capabilities we have, it’s unrealistic to launch in time.”

South Korean officials insisted they are not abandoning all future asteroid missions, but merely shifting this effort to other asteroids in which there is less time pressure to launch. Right now they are considering a mission in the mid-2030s, which could also be an asteroid sample return mission.

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Software issues delay Psyche launch seven weeks

9:05 am

Engineers preparing to stack the Psyche probe on top of its Falcon Heavy rocket for an August 1, 2022 launch have been forced to delay that launch at least seven weeks until September 20th at the earliest because of a software issue.

Technicians unboxed the Psyche spacecraft and moved it to a handling fixture for a series of hardware and software tests to make sure the probe survived the cross-country trip from California.

But a technical issue interrupted the test campaign, and will delay the launch of the Psyche mission at least seven weeks.

“An issue is preventing confirmation that the software controlling the spacecraft is functioning as planned,” NASA said in a written statement, responding to questions from Spaceflight Now. “The team is working to identify and correct the issue.”

Assuming no further delays, the spacecraft will still reach Psyche in January 2026.

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NASA extends eight planetary missions, including sending OSIRIS-REx to the asteroid Apophis

1:18 pm

Apophis' path past the Earth in 2029
Apophis’ path past the Earth in 2029.

NASA today announced that it is extending the missions of eight different planetary probes.

The missions – Mars Odyssey, Mars Reconnaissance Orbiter, MAVEN, Mars Science Laboratory (Curiosity rover), InSight lander, Lunar Reconnaissance Orbiter, OSIRIS-REx, and New Horizons – have been selected for continuation, assuming their spacecraft remain healthy. Most of the missions will be extended for three years; however, OSIRIS-REx will be continued for nine years in order to reach a new destination, and InSight will be continued until the end of 2022, unless the spacecraft’s electrical power allows for longer operations.

The biggest news is the decision to extend OSIRS-REx so that it can rendezvous with the asteroid Apophis in 2029. The science team…

…will redirect the spacecraft to encounter Apophis, an asteroid roughly 1,200 feet (roughly 370 meters) in diameter that will come within 20,000 miles (32,000 kilometers) of Earth in 2029. OSIRIS-APEX will enter orbit around Apophis soon after the asteroid’s Earth flyby, providing an unprecedented close-up look at this S-type asteroid. It plans to study changes in the asteroid caused by its close flyby of Earth and use the spacecraft’s gas thrusters to attempt to dislodge and study the dust and small rocks on and below Apophis’ surface.

Apophis is a potentially dangerous asteroid, with a 1 in 150,000 chance it will hit the Earth in 2068. Getting as much information about it as soon as possible is crucial so that future generations will be prepared should its path eventually become a collision course.

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Lucy team schedules attempt to complete solar panel deployment

3:21 pm

Lucy solar panel graphic
Artist’s impression of solar panel

After months of discussions, the engineering team of the Lucy asteroid probe have now scheduled the week of May 9th as when they will begin their attempt to complete the deployment of the spacecraft’ partly opened solar panel.

The team is now preparing to complete the solar array deployment in two steps. The first step, tentatively scheduled for the week of May 9, is intended to pull in most of the remaining lanyard and verify that flight results are consistent with ground testing. This step will also strengthen the array by bringing it closer to a fully tensioned state. Because this step is designed to be limited in duration, the array is not likely to latch at that point.

If this step goes as planned, the second step will continue the array deployment with the intent to fully latch. Information gleaned from the first part will help fine-tune the second. The second step is currently planned for a month after the initial one, giving engineers enough time to analyze the data seen in the first attempt.

When launched in October 2021 one of Lucy’s two large solar panels did not completely open and latch, as shown above. Though the spacecraft is presently getting 90% of its expected power, the scientists want to get the panel fully open and latched to insure it will function as planned once the spacecraft gets out to the asteroid belt, where sunlight is dimmer.

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