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 observe Jupiter because it orbits the Solar. Because it journeys to those Trojan asteroids, the probe is making ready for its second cease on the foremost belt, approaching a mysterious house rock to observe for the primary occasion.

NASA’s Lucy spacecraft will perform a flyby of the small foremost belt asteroid Donaldjohanson on April 20 at 1:51 p.m. ET, when it can 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 much more sophisticated than its first flyby, with NASA describing it as a “complete gown rehearsal for Lucy’s foremost mission,” the house 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) large. The asteroid is a fraction from a collision that befell round 150 million years in the past, making it one of many youngest foremost belt asteroids ever visited by a spacecraft.

Though it’s not a Trojan asteroid, it’s positioned in a handy spot for Lucy to swing by it on its strategy to the Jovian system. The upcoming flyby will present the group with a possibility to check Lucy’s programs 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 likely be turned away from Earth, suspending communication. For the rest of the flyby, Lucy will likely 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 can be similar to the one it can carry out as soon as it reaches the Trojans.

Round 40 seconds earlier than its closest method to the asteroid, nonetheless, Lucy will cease monitoring Donaldjohanson to guard its delicate devices from intense daylight. “In the event you 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 likely be reversed, so we have now to defend the devices in the identical method,” Michael Vincent of Southwest Analysis Institute (SwRI) in Boulder, Colorado, and encounter section lead of the mission, mentioned in an announcement. “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 can reestablish communication with Earth about an hour after its flyby, hopefully beaming again all the dear information it collected. The group, nonetheless, does need to 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 house missions is how sluggish the pace of sunshine is,” Vincent mentioned. “Lucy is 12.5 gentle 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, once we command the information playback after closest method, it takes 25 minutes from once 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 foremost belt asteroid Dinkinesh in November 2023. The mission’s first asteroid encounter was much more rewarding than initially anticipated because the brief rendezvous revealed a binary pair with the invention of a tiny satellite tv for pc intently orbiting Dinkinesh.

The mission’s major focus is finding out the Trojan asteroids, a bunch of rocky our bodies that lead and observe 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 special 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 an announcement. “The truth that every new asteroid we go to knocks our socks off means we’re solely starting to grasp the depth and richness of that historical past. Telescopic observations are hinting that Donaldjohanson goes to have an fascinating story, and I’m totally anticipating to be stunned—once more.”