OSIRIS-REx ‘GO’ for Sample Capsule Release

Following a team briefing minutes ago, operators gave the “go” for the OSIRIS-REx spacecraft to release its sample capsule. The poll of the lead engineers and military personnel was unanimous. 

Each team lead responded based on a list of criteria. Are projections showing that the capsule will land in its target area? Yes. Do the latest predictions of peak heat and peak deceleration levels that the spacecraft will endure still meet our expectations? Yes. Is the spacecraft ready to release the capsule and divert itself away from Earth? Yes. Is the team ready for the day? Yes. Is the range clear? Yes. 

Within an hour, engineers at Lockheed Martin’s Mission Support Area in Denver will send the release commands to the spacecraft, which will cause the spacecraft to release the capsule at about 6:42 a.m. EDT (4:42 a.m. MDT) from around 63,000 miles of Earth’s surface – about one-third the distance from Earth to the Moon. 

NASA’s live coverage of the OSIRIS-REx capsule landing starts at 10 a.m. EDT (8 a.m. MDT) and will air on NASA TV, the NASA app, and the agency’s website.

Favorable Weather Forecast for Sept. 24 Sample Return

A weather briefing today predicted a dry Sept. 24 with low winds. These are optimal conditions for NASA’s OSIRIS-REx sample recovery team: A wet and windy day would have made a speedy capsule recovery from the desert floor of the Department of Defense’s Utah Test and Training Range more difficult.

The OSIRIS-REx team will continue monitoring the weather on Sunday via balloons, the first to be released at 5 a.m. EDT (3 a.m. MDT), which will soar to around 60,000 feet above the military range to measure local temperature, humidity, air pressure, and wind. 

A landscape scene with green shrubs in the foreground and a mountain range stretching horizontally across the top half of the image. In the middle of the mounds of shrubs is flat, sand-colored ground.
The Department of Defense’s Utah Test and Training Range is seen, Monday, July 17, 2023. Credit: NASA/Keegan Barber

This morning, team members packed their supplies for the field and loaded their gear onto the helicopters and vehicles they’ll use Sunday morning to travel to the capsule’s landing location.  

NASA’s live coverage of the OSIRIS-REx capsule landing starts at 10 a.m. EDT (8 a.m. MDT) on Sunday, Sept. 24, and will air on NASA TV, the NASA app, and the agency’s website. 

OSIRIS-REx Makes Final Course Adjustment Before Sept. 24 Sample Delivery

On Sept. 17, NASA’s OSIRIS-REx engineers slightly shifted the spacecraft’s trajectory to refine the landing location of its sample capsule, which the spacecraft will deliver to Earth on Sept. 24. The spacecraft briefly fired its thrusters Sunday to change its velocity by 7 inches per minute (3 millimeters per second) relative to Earth.

This final correction maneuver moved the sample capsule’s predicted landing location east by nearly 8 miles, or 12.5 kilometers, to the center of its predetermined landing zone inside a 36-mile by 8.5-mile (58-kilometer by 14-kilometer) area on the Defense Department’s Utah Test and Training Range.

Sunday’s maneuver was a tweak of a critical maneuver on Sept. 10, which set the spacecraft on course to release its sample capsule, with rocks and dust from asteroid Bennu, from 63,000 miles (or 102,000 kilometers) above Earth’s surface this weekend.

The spacecraft is currently about 1.8 million miles, or 2.8 million kilometers, away, traveling at about 14,000 mph (about 23,000 kph) toward Earth.

– Lonnie Shekhtman

Calling Music Buffs: Help Make a Playlist for NASA’s OSIRIS-REx Sample Delivery

Calling all music buffs! This one’s for you. We’re gearing up for the Sept. 24 landing of NASA’s first asteroid sample and we want you to provide the soundtrack. Your song requests could be featured during a week of live episodes on Third Rock Radio and on the official Return of the Rock playlists. Third Rock Radio is a NASA- and space-themed online radio station.

From Sept. 18 to 22, Third Rock Radio will host daily OSIRIS-REx-themed shows from 3-5 p.m. EDT featuring your song suggestions on themes related to NASA’s daredevil mission. Third Rock Radio is produced and published by Houston-based RFC Media under a Space Act Agreement with NASA.

You can submit your song requests at Third Rock Radio or on NASA’s social media. Your name or social media handle and your song suggestion could end up on Third Rock Radio!

The daily themes are:

Monday, Sept. 18: Road Trip

Space is big and interplanetary travel takes a long time. OSIRIS-REx launched on Sept. 8, 2016, collected an asteroid sample in 2020, and now is returning to Earth to deliver the sample on Sept. 24. If you were riding along with OSIRIS-REx, what songs would you play to pass the time while you travel?

Tuesday, Sept. 19: Give Me the Rock

Asteroid Bennu is a rubble-pile asteroid, an amalgamation of rocks and dust held loosely together by microgravity. After OSIRIS-REx collected a sample from asteroid Bennu’s surface, scientists discovered that the asteroid was so loosely packed that if a person were to step onto it they would feel as if they were stepping into a child’s ball pit. To honor this rocky world, name a song that ROCKS!

Wednesday, Sept. 20: Time

On Sept. 24, OSIRIS-REx will deliver a capsule containing rocks and dust from asteroid Bennu that could be more than 4.5 billion years old. These rocks are a time capsule from the dawn of our solar system. Share your favorite songs related to time.

Thursday, Sept. 21: The Power of Science

From signs of ancient water on Bennu to particles spewing from its surface, OSIRIS-REx discoveries continue to surprise us. What surprises will we learn when scientists worldwide analyze the asteroid sample in their labs? Give us a song that is science related, or about inventions, discoveries, or anything else that gets you jazzed about the solar system!

Friday, Sept. 22: The Final Countdown

OSIRIS-REx is almost here with the asteroid sample! In these final moments, we need a soundtrack to pump us up and celebrate the hard work that has gone into this historic sample return mission.

The rules:

    1. Songs with explicit titles, lyrics and themes will not be played on air or appear in the playlists.
    2. Third Rock Radio has the flexibility to select which songs will air from the submissions. Third Rock Radio does not guarantee to play any specific song. Want to know if your submission made the cut? Don’t miss the live shows!

– Molly Wasser


OSIRIS-REx Adjusts Course to Target Sample Capsule’s Landing Zone

On Sept. 10, NASA’s OSIRIS-REx spacecraft briefly fired its ACS (attitude control system) thrusters to point itself toward Earth, putting it on course to release its sample capsule, carrying rocks and dust from asteroid Bennu, from 63,000 miles (or 102,000 kilometers) above Earth’s surface on Sunday, Sept. 24.

Yesterday’s trajectory-correction maneuver changed the spacecraft’s velocity about a ½ mph (less than 1 kph) relative to Earth. Without this tiny but critical shift, the spacecraft and its asteroid cargo would have flown past Earth.

On a black background – a star-studded sky – three bright yellow lines cut across the image, all pointing at and past an image of a blue and green planet.
This graphic shows the Earth return trajectory for the OSIRIS-REx spacecraft and for the sample capsule, after the spacecraft releases it above Earth on Sept. 24. The yellow diamonds indicate the dates of spacecraft maneuvers that slightly adjust its trajectory to get it closer, and then pointing at, and then above Earth. Credit: NASA’s Goddard Space Flight Center.

But now, the spacecraft is set up to release the capsule to enter the atmosphere just off the coast of California at 8:42 a.m. MDT / 10:42 a.m. EDT.

Traveling at a precise speed and angle, it will land approximately 13 minutes after release in a 36-mile by 8.5-mile (58-kilometer by 14-kilometer) predetermined area on the Department of Defense’s Utah Test and Training Range southwest of Salt Lake City.

Meanwhile, about 20 minutes after releasing the sample capsule, the spacecraft will fire its engines to divert past Earth and onto its next mission to asteroid Apophis: OSIRIS-APEX (OSIRIS-Apophis Explorer).

OSIRIS-REx may fire its thrusters again on Sept. 17 if engineers determine that one final adjustment to its trajectory is necessary before it releases its capsule a week later.

The spacecraft is currently 4 million miles, or 7 million kilometers, away, traveling at about 14,000 mph (about 23,000 kph) toward Earth.

– Lonnie Shekhtman

Here’s How Sept. 24 Asteroid Sample Delivery Will Work

Early morning on Sunday, Sept. 24, the OSIRIS-REx spacecraft’s sample capsule will come face-to-face with Earth’s atmosphere for the first time since the mission’s 2016 launch. On board are an estimated 8.8 ounces, or 250 grams, of rocky material collected from the surface of Bennu in 2020 – NASA’s first asteroid sample and the largest ever collected in space.

When it approaches Earth, the OSIRIS-REx spacecraft won’t slow down as it makes its sample drop-off. Instead, when it reaches 63,000 miles (or 102,000 kilometers) above Earth’s surface – about one-third the distance from Earth to the Moon – a message from operators on the ground will trigger the capsule’s release and the capsule will be sent spinning toward the atmosphere below. Twenty minutes after the drop-off, the spacecraft will fire its thrusters to divert past Earth toward asteroid Apophis, where it will continue investigating our solar system under a new name: OSIRIS-APEX (OSIRIS-Apophis Explorer).

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Meanwhile, after zooming through space for four hours, the capsule will pierce Earth’s atmosphere at 8:42 a.m. MDT (10:42 a.m. EDT), traveling about 27,650 mph (44,500 kph). At this pace, the compression of Earth’s atmosphere will produce enough energy to envelop the capsule in a superheated ball of fire. A heat shield will help to regulate the temperature inside the capsule, keeping the sample safe at a temperature similar to that of Bennu’s surface.

Parachutes will bring the capsule’s descent to a safe landing speed. A drogue parachute designed to provide a stable transition to subsonic speeds will deploy first, about 2 minutes after the capsule enters the atmosphere. Six minutes later – at about 1 mile (1.6 kilometers) above the desert – the main chute will unfurl, carrying the capsule the rest of the way to a 36-mile by 8.5-mile (58-kilometer by 14-kilometer) area on the military range. At touchdown, the capsule will have slowed to about 11 mph (18 kph).

Finally, just 13 minutes after entering the atmosphere, the capsule will be on Earth for the first time in seven years, awaiting the recovery team’s approach.

This graphic shows the events that happen between the time the OSIRIS-REx spacecraft releases its sample capsule to the time it lands in the Utah desert. Credit: Lockheed Martin.

About 20 minutes before the capsule lands, when it is still high above the veil of Earth’s atmosphere, the recovery field team will board four helicopters and head out into the desert. The infrared glow of the capsule’s heat signature will be tracked by thermal instruments until the capsule becomes visible to optical instruments, giving the recovery team a way to trace the capsule’s Earthbound path. The goal for the recovery team is to retrieve the capsule from the ground as quickly as possible to avoid contaminating the sample with Earth’s environment.

Once located and packaged for travel, the capsule will be flown via helicopter longline to a temporary clean room on the military range, where it will undergo initial processing and disassembly in preparation for its journey by aircraft to NASA’s Johnson Space Center in Houston, where the sample will be documented, cared for, and distributed for analysis to scientists worldwide.

– Nathan Marder