NASA, ULA set to launch historic Lucy mission early Saturday morning

Date:
Sat, 16 Oct 2021 00:09:09 +0000

Description:
NASA and ULA (United Launch Alliance) are set to launch NASAs next asteroid exploration mission The post NASA, ULA set to launch historic Lucy mission early Saturday morning appeared first on NASASpaceFlight.com .

FULL STORY ======================================================================

NASA and ULA (United Launch Alliance) are set to launch NASAs next asteroid exploration mission Lucy from Florida early Saturday morning, kickstarting the spacecrafts 12-year journey through the solar system. Liftoff of Atlas V and Lucy is currently scheduled for 5:34 AM EDT (09:34 UTC) on Saturday, October 16, from SLC-41 (Space Launch Complex 41) at Cape Canaveral Space Force Station in Florida.

The 45th weather squadron at Space Launch Delta 45 currently predicts a 90% chance of favorable weather at launch, with a 10% chance of a weather violation. The primary weather concern for launch is the cumulus cloud rule. The 45th weather squadron gives the backup launch date, Sunday, October 17, a 50% chance of favorable weather at launch.



Lucy and its mission

Lucy, led by NASAs Goddard Space Flight Center in Maryland, will represent
the thirteenth mission under NASAs Discovery Program. The Discovery Program
is a NASA solar system exploration program designed to select low-cost, deep space missions with the primary goal of researching a specific scientific
area in the solar system.

During its 12-year primary mission, Lucy will visit a total of eight asteroids. Seven of these asteroids are Trojan asteroids unique asteroids located at Jupiters L4 and L5 Lagrange points, 60 degrees ahead of and 60 degrees behind Jupiter, respectively.

Lucys goal is to thoroughly investigate these Trojan asteroids, which, until Lucy, have never been visited by another spacecraft. These asteroids could be remnants of the very first collisions in our solar system, so investigating them with a mission like Lucy will provide incredible data on our solar systems formation and past environment. The eight asteroids Lucy will visit during its mission. (Credit: NASA)

Whats more, the mission, upon its completion, will become the first
spacecraft to ever visit eight separate planetary bodies in a single mission. See Also Atlas V/Lucy Updates ULA Forum Section L2 HistoricalSection Click here to Join L2

However, for a mission as complex as Lucy, the spacecraft itself has to feature many unique instruments and systems to help it survive the harsh environment of space for twelve years while simultaneously collecting some
of the most valuable information on planetary formation to date.

When fully deployed in space, Lucy will span a massive 15.8 meters in width, 7.2 meters in height, and 2.78 meters in depth mostly due to the spacecrafts giant circular solar arrays.

Lucys solar arrays, once deployed, will be an impressive 7.3 meters in diameter, and will produce 504 watts of power at Lucys furthest distance from the Sun. Additionally, these solar arrays will make Lucy the farthest spacecraft to travel from the Sun that solely relies on solar power (all
other spacecraft have used nuclear power sources).

This particular design (of the circular solar arrays) enables us to stow up closely and tightly next to the spacecraft for launch, said Katie Oakman,
Lucy structures and mechanisms lead, of Lockheed Martin Space. Having any particular shape other than this really unique design wouldnt enable us to
get to that 51 square meters of active cell area, and still fit within a launch vehicle fairing. Lucy's gigantic solar arrays stretch out like a paper fan to 24 feet, or 7.3 meters. The arrays allow the spacecraft to travel farther from the Sun than any other solar-powered spacecraft to date,
explains @LockheedMartin engineer Katie Oakman. #LucyMission pic.twitter.com/PUloJ7zM68

NASA (@NASA) October 14, 2021



Lucys dry mass, or the mass of the spacecraft when unfueled, is 821 kg. Lucys wet mass, or the fuelled mass of the spacecraft, is 1550 kg.

Lucy will carry four primary instruments with it to the Trojan asteroids onboard an Instrument Pointing Platform (IPP). The instruments Lucy is carrying are: LRalph LLORRI LTES High Gain Antenna

LRalph will be used as a color visible imager and an infrared imaging spectrometer. MVIC, the color visible imager, will take standard color images of the Trojans, showing each asteroids unique activity and surface characteristics. The infrared imaging spectrometer, known as LEISA, will
allow Lucy to see absorption lines on asteroids that show different
silicates, ices, and organics that are present on Trojan asteroids to determine their composition and, critically, where in the solar system they formed before they were trapped in Jupiters Lagrange points.

Next is LLORRI, a high spatial resolution visible instrument that will take monochromatic images across the 0.35 to 0.85 microns wavelength. LLORRI will provide scientists with incredibly detailed images of the surface of the Trojans also revealing their sub-surface characteristics via impact craters. Lucy in the cleanroom prior to payload encapsulation (Credit: Thomas
Burghardt for NSF)

The L-TES instrument will use an infrared thermal emission spectrometer covering wavelengths of 6 to 75 microns. Having an infrared thermal emission spectrometer will allow scientists to learn more about a Trojan asteroids thermal inertia, body heat retainment, and surface material structure.

Lastly, Lucy will use its high gain antenna to measure the mass of each asteroid it passes using the Doppler shift of the radio signal from the antenna.

Lucy arrived in Cape Canaveral in late July and was sent to a cleanroom soon after its arrival. In the cleanroom, final tests on the spacecraft were performed, and Lucy was fueled for the final time before being stacked atop its Atlas V rocket.

Lucy was encapsulated in an Atlas V 4-meter payload fairing on September 29, and was transported to SLC-41 in the following days.

As Lucy was undergoing final integration, testing, and preparations for launch, ULA was also preparing the Atlas V rocket at SLC-41.

The Atlas V first stage supporting the launch of Lucy was previously assigned to the now-delayed Boeing OFT-2 (Orbital Flight Test 2) mission of Starliner in July. Following the extended delay of that mission, its Atlas V first
stage became available for use.

The Centaur upper stage, featuring one RL-10 engine, was stacked atop the Atlas first stage on September 16, marking the completion of the Atlas V rocket. No solid rocket motors are being used for this launch, meaning Atlas is launching in its 401 configuration (4-meter payload fairing, 0 solid
rocket motors, 1 RL-10 engine on the upper stage).

Lucy was stacked atop its Atlas V rocket on October 7, and Atlas V and Lucy rolled out to SLC-41 on October 14 for launch. Atlas 401 is poised on the pad and being prepared to launch the @LucyMission in under 24 hours. Launch time is set for 5:34 am EDT.

Tune into our @NASASpaceflight forum for updates: https://t.co/VPiIdgMuss pic.twitter.com/6UwFKbrlBy

Julia Bergeron (@julia_bergeron) October 15, 2021



Launch

In the hours leading up to launch, Atlas V will be filled with RP-1 Kerosene, Liquid Hydrogen, and Liquid Oxygen propellants for use during launch. Meanwhile, the ULA launch teams will monitor the rockets systems and Lucys condition.

At T-4 minutes, ULA launch teams will hold the count to undergo a final go/no-go poll for launch. This hold typically lasts 10 minutes and, once
Atlas V and Lucy are given the go for launch, the count will resume four minutes prior to liftoff.

Throughout the last four minutes of the countdown, ULA launch teams will monitor the health of the rocket and spacecraft. Finally, at T-2 minutes, the first stages Russian RD-180 engine will ignite, and Atlas V will liftoff from SLC-41.

At T+1:30, Atlas V will experience Max-Q, short for maximum aerodynamic pressure. Max-Q occurs when the aerodynamic loads on the vehicle are at their highest during ascent.

Following Max-Q, propellant levels in the first stage will deplete, and the RD-180 engine will be commanded to shut off in an event called booster engine cutoff (BECO). Spacecraft separation will follow six seconds later, at
T+4:09.

Over the next 42 minutes, the Centaur upper stage will ignite its RL-10
engine twice, starting with main engine start 1 (MES-1) at T+4:19. Payload fairing jettison occurs eight seconds after MES-1. ULA infographic showing
the planned trajectory of Atlas V during launch. (Credit: ULA)

Centaur will shut down for the final time at T+46:40 seconds and will enter a 12-minute coast phase in preparation for spacecraft separation. Lucy will separate from the Centaur upper stage at T+58:00, kicking off its 12-year mission through the solar system.

In the minutes following separation from Centaur, Lucy will unfold its
massive circular solar arrays and begin generating power to run its instruments and internal systems. Lucy will be on a trajectory that will take it out of Earths sphere of influence in the days following launch.

Lucy will coast through space for a year before it performs the first flyby
of its mission a flyby of Earth in October 2022. The spacecraft will use Earths gravity to adjust its orbit, in a maneuver called a gravity assist. Lucy will perform another Earth gravity assist in December 2024 before making the trek to the L4 Trojan asteroids.

However, before performing its L4 asteroid flybys, Lucy will first flyby asteroid 52246 Donaldjohanson on April 20, 2025. The flyby will largely serve as a dress rehearsal for Lucys Trojan flybys just as New Horizons used Jupiter as a practice target ahead of its eventual encounter with Pluto with the spacecraft using its IPP instruments and internal systems as it would
with a Trojan flyby.



Lucy will arrive at the L4 Trojan swarm (collections of Trojans) in 2027 and will kick off its Trojan flybys on August 12, 2027, when Lucy flies past 3548 Eurybates and its satellite, Queta.

One month later, on September 15, 2027, Lucy will fly by 15094 Polymele, the second of the seven Trojans the spacecraft will encounter. Next, Lucy will
fly past 11351 Leucus on April 18, 2028.

The last Trojan Lucy will encounter in the L4 swarm is 21900 Orus. Lucy will fly by the Trojan on November 11, 2028, and will exit the L4 swarm in the weeks following the flyby.

Lucy will then coast back to Earth for another gravity assist on December 25, 2030, slingshotting the spacecraft toward the L5 Trojan swarm.

Lucy will arrive at the L5 swarm in 2033 and will perform the final flyby of the primary mission on March 3, 2033, when it flies past Patroclus and Menoetius two, equal mass binary Trojans.

NASASpaceflight sat down with Lucys Principal Investigator, Dr. Hal Levison, to discuss the spacecrafts daunting trajectory in the weeks leading up to launch.

Lucys primary mission will conclude with the flyby of Patroclus and
Menoetius, but future mission extensions could see Lucy flyby other L4 and L5 Trojans if spacecraft power and fuel systems allow.

(Lead image: Atlas V at SLC-41 with Lucy via Stephen Marr for NSF)

The post NASA, ULA set to launch historic Lucy mission early Saturday morning appeared first on NASASpaceFlight.com .



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Link to news story: https://www.nasaspaceflight.com/2021/10/nasa-ula-launch-lucy/


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