NASA’s Lucy Spacecraft Set for Excessive-Stakes Asteroid Encounter on Sunday

The Lucy mission is on a 12-year journey to discover a peculiar set of asteroids that lead and comply with Jupiter because it orbits the Solar. Because it journeys to those Trojan asteroids, the probe is making ready for its second cease on the principal belt, approaching a mysterious area rock to observe for the principle occasion.

NASA’s Lucy spacecraft will perform a flyby of the small principal belt asteroid Donaldjohanson on April 20 at 1:51 p.m. ET, when it would come inside an eerily shut distance of 596 miles (960 kilometers) from the goal. That is Lucy’s second encounter with an asteroid, however it’s way more sophisticated than its first flyby, with NASA describing it as a “complete gown rehearsal for Lucy’s principal mission,” the area company wrote in a news release.

Lucy first laid its robotic eyes on Donaldjohanson in February and has been monitoring the asteroid over the previous two months to organize for its flyby. Donaldjohanson, named after the discoverer of the Lucy hominid fossil, is a carbonaceous asteroid that’s roughly 2.5 miles (4 km) broad. The asteroid is a fraction from a collision that occurred round 150 million years in the past, making it one of many youngest principal belt asteroids ever visited by a spacecraft.

Though it’s not a Trojan asteroid, it’s situated in a handy spot for Lucy to swing by it on its technique to the Jovian system. The upcoming flyby will present the staff with a chance to check Lucy’s techniques and perform observations utilizing all three of the spacecraft’s science devices.

The spacecraft will orient itself to trace the asteroid round half-hour earlier than its shut method. Throughout that point, Lucy’s high-gain antenna, which it makes use of to speak with floor management, will probably be turned away from Earth, suspending communication. For the rest of the flyby, Lucy will probably be by itself, autonomously rotating utilizing its terminal monitoring system to maintain Donaldjohanson in view. Lucy will then use its science devices to conduct statement sequences of the asteroid which might be similar to the one it would carry out as soon as it reaches the Trojans.

Round 40 seconds earlier than its closest method to the asteroid, nevertheless, Lucy will cease monitoring Donaldjohanson to guard its delicate devices from intense daylight. “If you happen to had been sitting on the asteroid watching the Lucy spacecraft approaching, you would need to defend your eyes staring on the Solar whereas ready for Lucy to emerge from the glare. After Lucy passes the asteroid, the positions will probably be reversed, so we have now to defend the devices in the identical approach,” Michael Vincent of Southwest Analysis Institute (SwRI) in Boulder, Colorado, and encounter section lead of the mission, mentioned in a press release. “These devices are designed to {photograph} objects illuminated by daylight 25 instances dimmer than at Earth, so trying towards the Solar may injury our cameras.”

After its closest method, the spacecraft will reorient its photo voltaic arrays again towards the Solar. It would reestablish communication with Earth about an hour after its flyby, hopefully beaming again all the dear information it collected. The staff, nevertheless, does must be affected person contemplating how far Lucy is from Earth, so the method will take a number of days.

“One of many bizarre issues to wrap your mind round with these deep area missions is how gradual the velocity of sunshine is,” Vincent mentioned. “Lucy is 12.5 mild minutes away from Earth, which means it takes that lengthy for any sign we ship to succeed in the spacecraft. Then it takes one other 12.5 minutes earlier than we get Lucy’s response telling us we had been heard. So, after we command the info playback after closest method, it takes 25 minutes from after we ask to see the images earlier than we get any of them to the bottom.”

Lucy launched in October 2021, and pulled off a flyby of the tiny principal belt asteroid Dinkinesh in November 2023. The mission’s first asteroid encounter was way more rewarding than initially anticipated because the brief rendezvous revealed a binary pair with the invention of a tiny satellite tv for pc carefully orbiting Dinkinesh.

The mission’s major focus is learning the Trojan asteroids, a bunch of rocky our bodies that lead and comply with Jupiter because it orbits the Solar. Lucy will start its tour of the Trojan asteroids in 2027 by visiting Eurybates and its binary accomplice Queta, adopted by Polymele and its binary accomplice, Leucus, Orus, and the binary pair Patroclus and Menoetius.

“Each asteroid has a unique story to inform, and these tales weave collectively to color the historical past of our photo voltaic system,” Tom Statler, Lucy mission program scientist at NASA, mentioned in a press release. “The truth that every new asteroid we go to knocks our socks off means we’re solely starting to know the depth and richness of that historical past. Telescopic observations are hinting that Donaldjohanson goes to have an attention-grabbing story, and I’m totally anticipating to be shocked—once more.”