Thursday, November 09, 2023

‘Puzzling’ discovery spotted in new images from NASA mission’s asteroid flyby

Ashley Strickland, CNN

Dinkinesh, a small asteroid that NASA’s Lucy mission visited last week, continues to surprise.

Lucy swung by the space rock, located in the main asteroid belt between Mars and Jupiter, on November 1 as part of a test of the spacecraft’s equipment before tackling the mission’s primary goal: surveying the swarms of Trojan asteroids around Jupiter. The flyby of Dinkinesh, which means “marvelous” in the Amharic language of Ethiopia, wasn’t even added to Lucy’s itinerary until January.

But the first views captured by Lucy’s instruments showed there was more to the shadowy asteroid than expected. At first, images suggested that the space rock was part of a binary pair, with a smaller asteroid orbiting Dinkinesh.

The first image taken by the spacecraft during its closest approach revealed the companion, but not the fact that it was a contact binary. - NASA/Goddard/SwRI/Johns Hopkins APL/NOIRLab

However, additional images taken by the spacecraft just after the flyby’s closest approach have now revealed that the smaller asteroid is actually a contact binary — two smaller space rocks that touch each other.

Lucy came within 265 miles (about 425 kilometers) of the asteroid’s surface during its closest approach, which is when the first images were taken. The second batch of images revealing the contact binary, shared by NASA on Tuesday, were taken six minutes later from 1,010 miles (about 1,630 kilometers) away.

“Contact binaries seem to be fairly common in the solar system,” said John Spencer, Lucy deputy project scientist at the Southwest Research Institute, in a statement.

“We haven’t seen many up-close, and we’ve never seen one orbiting another asteroid.
We’d been puzzling over odd variations in Dinkinesh’s brightness that we saw on approach, which gave us a hint that Dinkinesh might have a moon of some sort, but we never suspected anything so bizarre!”
Solving an asteroid enigma

The close approach was primarily designed to help the Lucy spacecraft test its terminal tracking system, which allows the spacecraft to locate the space rock autonomously and keep it within view while flying by at 10,000 miles per hour (4.5 kilometers per second). The system surpassed expectations, which allowed astronomers to make the discovery of Dinkinesh’s unexpected companion.

This graphic shows the Lucy spacecraft's trajectory as it flew by Dinkinesh and when it captured the images revealing the asteroid's surprising companion. - NASA/Goddard/SwRI

“It is puzzling, to say the least,” said Hal Levison, principal investigator for Lucy at the Southwest Research Institute, in a statement. “I would have never expected a system that looks like this. In particular, I don’t understand why the two components of the satellite have similar sizes. This is going to be fun for the scientific community to figure out.”

Data from the flyby is still transmitting from the spacecraft to the mission team.

“It’s truly marvelous when nature surprises us with a new puzzle,” said Tom Statler, Lucy program scientist at NASA, in a statement. “Great science pushes us to ask questions that we never knew we needed to ask.”
Setting a course for the Trojans

Lucy’s next close encounter will be with another main belt asteroid called Donaldjohanson in 2025. And then, the spacecraft will set off to see the Trojans.

The Trojan asteroids, which borrow their name from Greek mythology, orbit the sun in two swarms — one that’s ahead of Jupiter, the largest planet in our solar system, and a second one that lags behind it. Too distant to be seen in detail with telescopes, the asteroids will get their close-up when Lucy reaches the Trojans in 2027.

The mission borrows its name from the Lucy fossil, the remains of an ancient human ancestor discovered in Ethiopia in 1974. The skeleton has helped researchers piece together aspects of human evolution, and NASA Lucy team members hope their mission will achieve a similar feat regarding the history of our solar system.

The asteroids are like fossils themselves, representing the leftover material hanging around after the formation of giant planets in our solar system, including Jupiter, Saturn, Uranus and Neptune.


Strange moon of asteroid Dinkinesh is weirder than thought after NASA probe finds 'contact binary' (photo)

Brett Tingley
Tue, November 7, 2023

Three grey space rocks in the blackness of space. the largest is alone on the left; the smaller two are on the right, touching one another.

Asteroid Dinkinesh continues to surprise us.

On Nov. 1, NASA's Lucy spacecraft zoomed past this space rock, marking the first of several asteroid encounters the probe is designed to make. Lucy's goal is to ultimately explore a set of asteroids near Jupiter, known as the Trojans, which are thought to hold clues about the earliest days of our solar system; these objects may be able to shed light on the origins of life on Earth. But, on the way to those Trojans, Lucy has a couple of stops — including Dinkinesh, which sits in the main asteroid belt between Mars and Jupiter.

On Nov. 2, project scientists with the Lucy mission announced the first flyby came with a surprise: Dinkinesh, or 'Dinky,' appears to be not one asteroid, but two. Lucy was able to observe that Dinkinesh is a binary system, meaning there is a small natural satellite in orbit around it.

And today (Nov. 7), scientists announced another surprise.

In a NASA statement, the Lucy team writes that Dinky's smaller satellite is itself a type of binary system known as a "contact binary," meaning the two smaller objects are in contact with one another. This means Dinky isn't made up of one, or two, but rather three components.

"It is puzzling, to say the least," the Southwest Research Institute's Hal Levison, principal investigator for Lucy, said in the statement. "I would have never expected a system that looks like this. In particular, I don't understand why the two components of the satellite have similar sizes. This is going to be fun for the scientific community to figure out."

Related: Surprise! Asteroid 'Dinky' is actually a double space rock, NASA's Lucy probe reveals (photo)

Lucy spotted the third rock in this asteroid system six minutes after snapping the images that initially revealed Dinkinesh wasn't alone. In that time, the probe had traveled 960 miles (1,545 km) from the point at which it discovered the first satellite.

Contact binary systems seem to be fairly common throughout our solar system, but scientists hadn't seen one orbiting another asteroid prior to Dinkinesh, Lucy's deputy project scientist John Spencer said in the statement. "We'd been puzzling over odd variations in Dinkinesh's brightness that we saw on approach, which gave us a hint that Dinkinesh might have a moon of some sort, but we never suspected anything so bizarre!"

two grey rocks tumble in space

— Meet Dinkinesh: Asteroid targeted by NASA's Lucy spacecraft gets a marvelous name

Again, however, Dinkinesh and its two satellites are only the first of many asteroids Lucy will visit during its planned 12-year mission that began in Oct. 2021, when it launched from Kennedy Space Center atop a United Launch Alliance (ULA) Atlas V rocket.

After leaving Dinky, the probe will head back to Earth for a gravity assist maneuver in December 2024. This assist is expected to slingshot the probe back out to the main asteroid belt, where it will study the asteroid Donaldjohanson in 2025.

From there, Lucy will move on to its main goal: The Trojan asteroids.

The spacecraft will become the first mission to visit these early solar system relics, and if all goes according to plan, Lucy will visit eight different Trojan asteroids between 2027 and 2033. Possibly, the spacecraft will uncover more space rock surprises along the way.

"It's truly marvelous when nature surprises us with a new puzzle," Tom Statler, Lucy program scientist from NASA Headquarters in Washington, said in the statement. "Great science pushes us to ask questions that we never knew we needed to ask."

Another Lucy Bonus: Asteroid's Surprise Moon Is Actually Two Rocks Stuck Together

Passant Rabie
Tue, November 7, 2023

The first look at the Dinkinesh asteroid revealed a surprise: The small space rock had its own moon. Now as the Lucy spacecraft downlinked more images of its first target, it showed not one but two tiny asteroids orbiting around Dinkinesh.

NASA’s Lucy mission made a close flyby of the Dinkinesh asteroid on November 1, capturing data about the rocky object in the main asteroid belt. As it turns out, this small little guy was hiding a big secret: a tiny moon. But that’s not the only surprise; Dinkinesh is no ordinary binary system—it hosts a satellite that’s a contact binary consisting of two smaller objects in direct contact, NASA announced on Tuesday. The surprise space rocks are the first contact binary orbiting asteroid to ever be observed.

At its closest approach, Lucy captured its first set of images when it was around 265 miles (425 kilometers) away from the asteroid. Six minutes later, the spacecraft captured its second set of images when it was at a distance of 1,010 miles (1,630 km) from the asteroid.

“It is puzzling, to say the least,” Hal Levison, principal investigator for Lucy at the Southwest Research Institute, said in a statement. “I would have never expected a system that looks like this. In particular, I don’t understand why the two components of the satellite have similar sizes. This is going to be fun for the scientific community to figure out.”

Dinkinesh, which roughly translates to “marvelous” in Amharic, is around 0.5 miles (790 meters) at its widest. The small asteroid was added to the mission’s itinerary in January as a way to test the spacecraft’s terminal tracking system, which is used for precise imaging during its high speed encounters with the asteroids.

Although it was only meant to be a test of its systems, Lucy’s brief encounter with Dinkinesh is the gift that keeps on giving. The spacecraft itself has moved on already, and is currently headed back toward Earth for a gravity assist in December 2024 that will propel it back towards the main asteroid belt for a close flyby of asteroid Donaldjohanson in 2025.

After its two early targets, the mission will begin its tour of the Trojan asteroids, a group of space rocks that lead and follow Jupiter in its orbit around the Sun. Lucy will reach the Trojan asteroids in 2027, visiting Eurybates and its binary partner Queta, followed by Polymele and its binary partner, Leucus, Orus, and the binary pair Patroclus and Menoetius.

The mission team still has plenty of time to downlink the remaining data and images from Lucy’s first asteroid encounter, which have led to uncovering more mysteries than they had initially anticipated. “It’s truly marvelous when nature surprises us with a new puzzle,” Tom Statler, Lucy program scientist from NASA, said in a statement. “Great science pushes us to ask questions that we never knew we needed to ask.”


Nasa gets ‘puzzling’ data back from Lucy spacecraft exploring distant object

Andrew Griffin
Wed, November 8, 2023 

The space agency’s Lucy Spacecraft left Earth in 2021, with the aim of studying “Jupiter trojans”, a set of asteroids that fly around the Sun along Jupiter’s orbit and remain largely mysterious. Recently, scientists decided to send it to visit another small object on its way, largely as a test of the systems on the spacecraft that let it track asteroids for its mission.

When Lucy arrived at that object – a main belt asteroid named Dinkinesh – it found a surprise, however. Images taken of the asteroid showed that it had a satellite, which flies around the asteroid like a tiny moon of its own.

Now, further examination of those images show that the satellite is not one but two objects. Those objects make up a “contact binary”, or two smaller objects that are touching each other as they fly through space.

The unexpected discovery explains some of the strange data that scientists had received as they approached Lucy. But it opens up more confusion about the whole system, which one called “bizarre”.

“Contact binaries seem to be fairly common in the solar system,” said John Spencer, Lucy deputy project scientist, in a statement. “We haven’t seen many up-close, and we’ve never seen one orbiting another asteroid.

“We’d been puzzling over odd variations in Dinkinesh’s brightness that we saw on approach, which gave us a hint that Dinkinesh might have a moon of some sort, but we never suspected anything so bizarre!”

The flyby of Dinkinesh was only intended as a test of the spacecraft’s systems but has now posed new possible research for scientists.

“It’s truly marvelous when nature surprises us with a new puzzle,” said Tom Statler, Lucy program scientist from NASA Headquarters in Washington. “Great science pushes us to ask questions that we never knew we needed to ask.”

“It is puzzling, to say the least,” said Hal Levison, principal investigator for Lucy, also from Southwest Research Institute. “I would have never expected a system that looks like this. In particular, I don’t understand why the two components of the satellite have similar sizes. This is going to be fun for the scientific community to figure out.”

The scientists were only able to confirm the nature of the system with the multiple images that were sent back by Lucy in the wake of its encounter with Dinkinesh. Nasa is working now to get the rest of the data from the spacecraft, which might include yet more surprises.

Lucy itself will continue flying through space on a journey that is due to take 12 years. Lucy is actually heading back to Earth, which it will use for a gravity assist to propel it onto the next part of its journey, back through the main asteroid belt and onto the Trojan asteroids.

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