- 4165 - ASTEROID SAMPLE RETURN - Largest asteroid sample ever collected is coming down to Earth. Chunks of asteroid that could tell us about the earliest days of the 4.5 billion-year-old solar system and the possible origins of water on our planet are set to land in the Utah desert in 2023
-------------- 4165 - ASTEROID SAMPLE RETURN
- This sample return
is more than a decade in the making for a NASA mission called “OSIRIS-REx”. Its
goal was to scoop up a large sample of rocks and dust from a near-Earth
asteroid named Bennu and bring it to our planet to study.
-
- The sample returned
will help scientists get a snapshot of what materials were present when our
solar system first formed. Researchers believe asteroids like Bennu haven't changed
much since the birth of our cosmic neighborhood. They plan to study the
recovered rocks and use the mission to inform future exploration.
-
- Asteroids could
have been the source material not just for building up the rocky parts of our
planet, but also for delivering the water that makes up our hydrologic system.
-
- Scientists don't
know exactly how much sample is in the container, but suspect it's the most
ever collected from an asteroid, weighing roughly 250 grams. That will give
them more rocks to analyze than ever before.
-
- The spacecraft left
Bennu with this sample in 2021, and has been en route to Earth ever since.
First, the probe will release the sample container, roughly the size of a tire,
into space.
-
- If that goes well,
from there it will make its way down to the planet, taking roughly four hours
to reach Earth's atmosphere. During that time, there's no way to control the
capsule. Once we release it, it's really
just a ballistic object.
-
- The container will
come into the atmosphere at about 27,000 miles per hour and heat up to around
5,000 degrees Fahrenheit. It has a heat shield, a critical piece of hardware
meant to prevent the sample from burning up.
-
- As it descends,
the capsule will release a drogue parachute to keep it steady, followed by
another parachute to slow it down. If all goes to plan, the capsule will gently
touch down in Utah at 10 to 11 miles per hour.
-
- From there, a
helicopter will tow it via cable to a clean room, where a nitrogen purge will
rid it of possible contaminants. Then it will head to NASA's Johnson Space
Center in Houston.
-
- No other country has
fetched pieces of asteroids, preserved time capsules from the dawn of our solar
system that can help explain how Earth—and life—came to be. The landing concludes a 4 billion-mile
journey highlighted by the rendezvous with the carbon-rich Bennu, a unique pogo
stick-style touchdown and sample grab, a jammed lid that sent some of the stash
spilling into space, and now the return of NASA's first asteroid samples.
-
- THE LONG
JOURNEY - Asteroid chaser Osiris-Rex blasted off on the
$1 billion mission in 2016. It arrived at Bennu in 2018 and spent the next two
years flying around the small spinning space rock and scouting out the best
place to grab samples. Three years ago, the spacecraft swooped in and reached
out with its 11-foot (3-meter) stick vacuum, momentarily touching the
asteroid's surface and sucking up dust and pebbles.
-
- ASTEROID
BENNU -
Discovered in 1999, Bennu is believed to be a remnant of a much larger
asteroid that collided with another space rock. It's barely one-third of a mile
wide, roughly the height of the Empire State Building, and its black rugged
surface is packed with boulders. Roundish in shape like a spinning top,
-
- Bennu orbits the
sun every 14 months, while rotating every four hours. Scientists believe Bennu
holds leftovers from the solar system's formation 4.5 billion years ago. It may
come dangerously close and strike Earth on Sept.ember 24, 2182—exactly 159
years after the asteroid's first pieces arrive.
-
- Osiris-Rex's
up-close study can help humanity figure out how to deflect Bennu if needed.
-
- Osiris-Rex will release the sample capsule
from 63,000 miles out, four hours before it's due to touch down at the Defense
Department's Utah Test and Training Range on Sunday morning. The release
command will come from spacecraft builder Lockheed Martin's control center in
Colorado.
-
- Soon afterward,
the mothership will steer away and take off to explore another asteroid. The
capsule, 3 feet wide and 1.6 feet tall, will hit the atmosphere at 27,650 mph
for the final 13 minutes of descent remaining. The main parachute will slow the
last mile, allowing for a mild 11 mph touchdown.
-
- Once everything is deemed safe, the capsule
will be hustled by helicopter to a makeshift clean lab at the range. The next
morning, a plane will carry the sealed container full of rubble to Houston,
home to NASA's Johnson Space Center. NASA is livestreaming the touchdown.
-
- CLEANER THAN
CLEAN -
A new lab at Johnson will be limited to the Bennu rubble to avoid
cross-contamination with other collections.
Building 31 already holds the moon rocks brought back by the Apollo
astronauts from 1969 through 1972, as well as comet dust and specks of solar
wind collected during two previous missions and Mars meteorites found in
Antarctica. The asteroid samples will be handled inside nitrogen-purging
gloveboxes by staff in head-to-toe clean room suits.
-
- This fall is what
NASA is calling Asteroid Autumn, with three asteroid missions marking major
milestones. The Osiris-Rex touchdown will be followed by the launch of another
asteroid hunter on October 5, 2021. Both the NASA spacecraft and its target—a
metal asteroid—are named “Psyche”.
-
- Then a month
later, NASA's Lucy spacecraft will encounter its first asteroid since soaring
from Cape Canaveral, Florida, in 2021. Lucy will swoop past Dinkinesh in the
main asteroid belt between Mars and Jupiter on Nov. 1. It's a warmup for Lucy's
unprecedented tour of the so-called Trojans, swarms of asteroids that shadow
Jupiter around the sun. Neither Psyche nor Lucy will collect souvenirs, nor
will Osiris-Rex on its next assignment, to explore the asteroid Apophis in
2029.
-
- OTHER SAMPLE
RETURNS - This is NASA's third sample return from deep
space, not counting the hundreds of pounds of moon rocks gathered by the Apollo
astronauts. The agency's first robotic sample grab ended with a bang in 2004.
The capsule bearing solar wind particles slammed into the Utah desert and
shattered, compromising the samples.
-
- Two years later, a
U.S. capsule with comet dust landed intact. Japan's first asteroid sample
mission returned microscopic grains from asteroid Itokawa in 2010. It's second
trip yielded about 5 grams from the asteroid Ryugu in 2020. The Soviet Union
transported moon samples to Earth during the 1970s, and China returned lunar
material in 2020.
-
-
September 23, 2023 ASTEROID SAMPLE
RETURN 4165
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