NASA’s mission to asteroid Lucy 10 days before launch – Spaceflight Now

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NASA’s Lucy spacecraft was ready to be encapsulated last month in the payload fairing of its Atlas 5 launcher. Credit: NASA / Ben Smegelsky

Fueled for a 12-year exploration mission, NASA’s science probe Lucy is nearly ready to launch on October 16 from the space coast of Florida to begin a journey through the solar system to visit eight asteroids, a number record for a single spaceship.

Ground crews completed testing of the Lucy spacecraft last month in an air-conditioned cleanroom at the Astrotech payload processing facility in Titusville, Fla., A few miles from the gates of NASA’s Kennedy Space Center.

The tests capped a two-month campaign at Astrotech since the Lucy spacecraft arrived from its Lockheed Martin factory in Colorado. Techs loaded hydrazine and nitrogen tetroxide thrusters into the probe to power its small maneuver thrusters and main engine, which will help steer Lucy towards her asteroid targets.

“Lucy is done and we’re ready to fly,” said Hal Levison, the mission’s principal investigator at the Southwest Research Institute, or SWRI, in Boulder, Colorado.

The $ 981 million mission will be the first to explore a population of asteroids called the Trojans, which orbit the sun in front of and behind Jupiter.

Scientists believe Trojan asteroids represent a diverse cross section of the types of small planetary building blocks left behind after the solar system formed 4.5 billion years ago. Lucy will fly over eight different asteroids from 2025 to 2033, including seven in the Trojan swarms.

The 3,300-pound (1,500-kilogram) Lucy spacecraft is scheduled to be launched aboard an Atlas 5 rocket on October 16 during a 75-minute window opening at 5:34 a.m. EDT (08:34 GMT). The mission has 23 days to take off and take advantage of a unique alignment between Earth and the asteroids of the Outer Solar System.

If anything is preventing the launch this year, NASA has a back-up opportunity to launch Lucy in October 2022 with no impact on the science goals of the mission.

But the launch campaign went well in Florida, and officials overcame hurdles associated with the COVID-19 pandemic to keep Lucy on schedule.

“The pandemic has hit us at a truly inopportune time,” said Arlin Bartels, Lucy’s deputy project manager at NASA’s Goddard Space Flight Center. “It hit just as the instrument teams were just starting their manufacturing and testing.

“More than 400 components go into the spacecraft. We were still in the supply chain phase at that time. Planetary launch periods are very ruthless at the best of times because everything has to happen on schedule, ”Bartels said. “Trying to do this during a pandemic like this is a very intimidating situation, and I’m not sure everyone, when the pandemic hit, thought we would be able to see this in time.”

But engineers finished assembling the spacecraft, secured its three science instruments, finished building the probe’s fan-shaped solar panels, and put Lucy through a battery of tests to make sure it will survive. the rigors of launch and deep space operations.

“We are not working on anything on the spacecraft or the launcher that concerns us at the moment,” said Omar Baez, NASA launch director for the Lucy mission.

Last Friday, the United Launch Alliance completed a countdown dress rehearsal at Cape Canaveral. The launch team loaded kerosene, liquid hydrogen, and liquid oxygen into the Atlas 5 rocket on Mission Lucy, verifying that the launcher and ground systems are ready for the real countdown.

“We came out of this test Friday night in good shape, so the vehicle is ready to accept the encapsulated Lucy spacecraft,” Baez said in an interview with Spaceflight Now. “So we are ready to go. “

Inside Astrotech’s payload processing facility in Titusville, Fla., Ground crews prepare to encapsulate NASA’s Lucy spacecraft inside its payload fairing. Atlas 5 launcher. Credit: NASA / Ben Smegelsky

As ULA tested the Atlas 5 rocket last week, workers at Astrotech’s payload processing facility encapsulated the Lucy spacecraft inside the Atlas 5’s nose fairing. Aerodynamic fairing will protect the probe during the last preparations before launch and will protect the craft during the first minutes of the climb in space.

The 13.8-foot-diameter (4.2-meter) payload fairing, produced by ULA in Harlingen, Texas, features the Lucy Mission logo. The badge features a pictorial illustration of the fossilized remains of a human ancestor, named Lucy by scientists who discovered her in Ethiopia in 1974.

Lucy’s skeleton became the namesake of the asteroid mission Lucy.

As the discovery of fossils informed scientists about human evolution, Trojan asteroids could provide clues to the ancient history of the solar system. After Jupiter formed and settled in its current orbit, the asteroids found themselves trapped in swarms, each centered on a gravitationally stable release point in front of and behind the largest planet in the solar system.

Lucy, the fossil, got her name after scientists heard the Beatles song “Lucy In The Sky With Diamonds” while celebrating the find. Scientists who developed the Trojan Asteroid Explorer saw the connection.

“These asteroids are really like diamonds in the sky in terms of their scientific value in understanding how giant planets formed and the solar system evolved,” Levison said.

“This fossil has transformed our understanding of hominid evolution, just as we hope the Lucy spacecraft will transform our understanding of the solar system,” said Cathy Olkin, deputy senior researcher for the mission at SWRI.

NASA selected the Lucy mission, along with another explored asteroid named Psyche, for development in 2017. Psyche is slated to launch next year to orbit a metal-rich asteroid.

Researchers believe the Trojan asteroids are remnants of the earliest period in the history of the solar system, when similar small objects clustered together to form the gas and glacial planets of the outer solar system.

During her mission, Lucy will fly over seven Jupiter Trojan asteroids. This time-lapse animation shows the movements of the inner planets (Mercury, brown; Venus, white; Earth, blue; Mars, red), Jupiter (orange) and the two Trojan swarms (green) during the Lucy mission. Credit: CAS Institute of Astronomy / Petr Scheirich

“If this whole story is true, and Lucy is going to test some of these hypotheses, these objects really represent objects that formed all over the Outer Solar System, and are now in the Swarms of Troy, where a mission like Lucy can. go study them, ”Levison said.

Scientists know little about Trojan asteroids. Lucy will be the first spacecraft to ever fly over the Trojan swarms, where researchers have found more than 7,000 small objects. There are perhaps thousands more waiting to be discovered using large telescopes.

But even the Hubble Space Telescope cannot work out the details about the makeup and appearance of Trojan asteroids. Scientists have a rough approximation of the size of each object to be visited by Lucy, and know a little about their colors. Some are gray and some are more reddish in appearance.

After taking off from Cape Canaveral, the Lucy spacecraft will spend a year in an Earth-like orbit around the sun, before returning to its home planet next October for a gravity-assisted slingshot maneuver to begin heading. to the solar system.

A second flyby of Earth in December 2024 will send Lucy to her first encounter with an asteroid. The spacecraft will pass by asteroid Donaldjohanson, named after the scientist who discovered Lucy’s fossil, in April 2025.

Next, Lucy will fly in the first swarm of Trojans, visiting five asteroids – including a tiny moon from one of the objects – in just 15 months between August 2027 and November 2028.

The Lucy spacecraft is seen on September 29 between the two halves of the Atlas 5 rocket payload fairing. Credit: Stephen Clark / Spaceflight Now

At her farthest arc, Lucy will be over 500 million miles (800 million kilometers) from the sun. The spacecraft will be the furthest spacecraft from the sun to ever use solar power.

A final movement of Earth in 2030 will prepare Lucy for the final encounter of the 12-year mission, a flyby of a binary pair of asteroids named Patroclus and Menoetius in March 2033. Each of the two objects is roughly the same size, with diameters of over 60 miles (100 kilometers), making them the largest targets of Lucy’s stay in the solar system.

At each asteroid, Lucy will only have a few hours to take the best photos and gather the most useful data. The probe will pass near asteroids at a relative speed of several kilometers per second, using a gimbal instrument platform to point its camera and scientific instruments.

“Lucy is a flyover mission, so after spending years traveling over a billion miles to reach our targets, we aim almost directly at them, flying within 600 miles (1,000 kilometers) of their surfaces.” NASA project scientist Keith Noll said. for the Lucie mission. “And Lucy doesn’t slow down for those flyovers.”

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Follow Stephen Clark on Twitter: @ StephenClark1.



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