OSIRIS-APEX – OSIRIS-REx Mission

Brian May Guest Blog: Stereoscopic Images from NASA’s OSIRIS-REx Sampling Head

Making stereoscopic images of asteroid Bennu was not part of the brief of NASA’s OSIRIS-REx mission; but we civilians, Claudia Manzoni and myself, were invited by mission principal investigator Dante Lauretta to join the science team and find opportunities for stereoscopy in the wealth of visual data acquired by the spacecraft’s cameras at Bennu.

To do this, we looked for pairs of images of Bennu’s surface taken from viewpoints some distance apart. This separation of viewpoints, known as the “baseline,” has to be just right to give us the experience of depth and reality when the images are viewed stereoscopically. Such viewing requires the left and right images to be delivered separately to our left and right eyes, which is how we see in “real life.” When this is done, the small differences between the components of the stereo pair – known as parallax differences – give our brains the opportunity to instantaneously perceive depth and solidity in the image.

These stereoscopic images are a pair of close-ups of ancient asteroid Bennu material retrieved by NASA’s OSIRIS-REx mission and delivered to Earth on Sept. 24, 2023. The material is on top of the TAGSAM (Touch-and-Go Sample Acquisition Mechanism), the instrument used to collect the sample from the asteroid in 2020. The sample and TAGSAM are currently in a clean room within the Astromaterials Curation Facility at NASA’s Johnson Space Center in Houston. Credit: Erika Blumenfeld, Joseph Abersold for the original images/Brian May, Claudia Manzoni for stereo processing of the images.

In the case of the images shown here, with the Bennu sample safely delivered to planet Earth, the curation team made it easy for us. In the moments when the TAGSAM head was flipped over after removing it from the avionics deck at NASA’s Johnson Space Center in Houston, photographs from many angles were captured, enabling us to find just one (nearly!) perfect pair, showing the intimate structure of just a few grains of the dark, coal-black sample.

It’s possible to view this side-by side stereoscopic pair without a stereoscope, by relaxing the axes of the eyes, as if staring through the screen to infinity. But the best experience will be had by using a stereoscope, the same way the OSIRIS-REx mission team viewed our stereo images while the search was on to find a safe spot on asteroid Bennu’s surface for the delicate Touch-and-Go sampling maneuver.

The largest “boulders” in this picture are about 1 centimeter across. Enjoy this piece of history in the making!

–Brian May

NASA’s OSIRIS-REx Spacecraft Views Sample Return Capsule’s Departure

After years of anticipation and hard work by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification and Security – Regolith Explorer) team, a capsule of rocks and dust collected from asteroid Bennu returned to Earth on Sept. 24 in a targeted area of the Department of Defense’s Utah Test and Training Range near Salt Lake City.

A few hours before the landing, OSIRIS-REx took some of its final views of its own sample return capsule.

This image of the OSIRIS-REx sample return capsule still attached to the spacecraft’s instrument deck was captured by the spacecraft’s StowCam camera on Sept. 23 at 10:37:55 a.m. EDT (14:37:55 UTC), less than 24 hours before the capsule’s release. StowCam, a color imager, is one of three cameras comprising TAGCAMS (the Touch-and-Go Camera System), which is part of OSIRIS-REx’s guidance, navigation, and control system. TAGCAMS was designed, built, and tested by Malin Space Science Systems; Lockheed Martin integrated TAGCAMS to the OSIRIS-REx spacecraft and operates TAGCAMS. Credit: NASA/Goddard/University of Arizona/Lockheed Martin

This black-and-white sequence of OSIRIS-REx’s sample return capsule descent toward Earth comes from TAGCAMS’s NavCam 1 and was taken in the moments after the capsule’s release from the spacecraft on Sept. 24, 2023. The Sun is visible at the top of the frame, and a thin “crescent Earth” can be seen at the left edge of the image. OSIRIS-REx’s NavCams are used for optical navigation of the spacecraft. NavCam images tracked star-fields and landmarks on Bennu to determine the spacecraft’s position during mission operations. This sequence of images has been processed to remove most of the scattered sunlight, bring out more detail of the capsule and release debris cloud, and prevent the Earth crescent from saturating. Credit: NASA/Goddard/University of Arizona/Lockheed Martin

Charred from its journey through Earth’s atmosphere, the OSIRIS-REx sample return capsule is shown here shortly following its landing on Sept. 24 in Utah’s Great Salt Lake Desert. Shortly after this photo was taken, the capsule was transported to a temporary clean room at the Department of Defense’s Utah Test and Training Range, and then flown on Sept. 26 to Houston and transported to NASA’s Johnson Space Center there. Credit: NASA/Keegan Barber

Following a flight aboard a U.S. Air Force C-17 aircraft on Sept. 26, the OSIRIS-REx sample return capsule was taken into a customized clean room at NASA’s Johnson Space Center in Houston. Meanwhile, the OSIRIS-APEX spacecraft – on a new mission with a new name – is on a course toward asteroid Apophis, which it will reach in 2029.

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

2020 – 2023: Touchdown! And Goodbye

This week, we have been recapping noteworthy OSIRIS-REx mission events each day so you can catch up on anything you may have missed so far on NASA’s first mission to collect a sample from an asteroid.

(Post #4 in a series of four)

At 1:50 p.m. EDT on Oct. 20, 2020, NASA’s OSIRIS-REx spacecraft fired its thrusters to nudge itself out of orbit around Bennu. It extended the shoulder, then elbow, then wrist of its 11-foot (3.35-meter) sampling arm and transited across Bennu while descending about half a mile (805 meters) toward the surface. After about a four-hour autonomous descent to a 26-foot- (8-meter-) wide spot on Bennu, past menacing boulders that could tip the spacecraft or the sample head and thwart the sample grab, OSIRIS-REx contacted the surface. It then fired a burst of nitrogen gas that stirred up dust and rocks, which were captured by the sample-collection head. Finally, OSIRIS-REx fired its thrusters and safely backed away from Bennu, allowing a captivated global audience to breathe a collective sigh of relief.

Before departing Bennu, OSIRIS-REx conducted one last flyby of the sample site, “Nightingale,” so scientists could see how the spacecraft’s contact with Bennu’s surface altered the site. They saw something astonishing: Even though the spacecraft barely touched the surface, it left a sizeable crater and scattered many rocks. Scientists ran hundreds of computer simulations to understand how this could have happened, given they had expected the spacecraft to leave only a small divot in the surface.

That’s when they learned that the particles making up Bennu’s exterior are loosely packed and lightly bound to each other, which means they act more like a fluid than a solid. Had it not fired its thrusters to back away immediately after grabbing a sample, OSIRIS-REx would have sunk into Bennu.

On May 10, 2021, the spacecraft departed Bennu and headed back toward Earth to drop off the sample-return capsule. When it arrives here on Sept. 24, 2023, OSIRIS-REx will release its sample capsule to land on Earth in the Utah desert, but the spacecraft will not land itself. With the sample delivered, the spacecraft will set off on a new mission, OSIRIS-APEX (OSIRIS-Apophis Explorer), to explore asteroid Apophis.