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 getting ready for its second cease on the major belt, approaching a mysterious area rock to apply for the principle occasion.

NASA’s Lucy spacecraft will perform a flyby of the small major belt asteroid Donaldjohanson on April 20 at 1:51 p.m. ET, when it’s going to 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 major 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 arrange 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) vast. The asteroid is a fraction from a collision that happened round 150 million years in the past, making it one of many youngest major 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 solution to the Jovian system. The upcoming flyby will present the workforce 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 strategy. Throughout that point, Lucy’s high-gain antenna, which it makes use of to speak with floor management, shall be turned away from Earth, suspending communication. For the rest of the flyby, Lucy shall be by itself, autonomously rotating utilizing its terminal monitoring system to maintain Donaldjohanson in view. Lucy will then use its science devices to conduct commentary sequences of the asteroid which are similar to the one it’s going to carry out as soon as it reaches the Trojans.

Round 40 seconds earlier than its closest strategy to the asteroid, nonetheless, Lucy will cease monitoring Donaldjohanson to guard its delicate devices from intense daylight. “In the event you have 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 shall be reversed, so we have now to defend the devices in the identical manner,” 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 occasions dimmer than at Earth, so wanting towards the Solar might harm our cameras.”

After its closest strategy, the spacecraft will reorient its photo voltaic arrays again towards the Solar. It should reestablish communication with Earth about an hour after its flyby, hopefully beaming again all the valuable knowledge it collected. The workforce, nonetheless, 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 sluggish the pace 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 have been heard. So, after we command the info playback after closest strategy, it takes 25 minutes from after we ask to see the photographs earlier than we get any of them to the bottom.”

Lucy launched in October 2021, and pulled off a flyby of the tiny major 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 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 companion Queta, adopted by Polymele and its binary companion, 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 a press release. “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 absolutely anticipating to be stunned—once more.”