Justice League | Alejandro Germánico Benit

How Exactly Do We Plan to Bring an Asteroid Sample Back to Earth?

Our OSIRIS-REx spacecraft launches tomorrow, and will travel to a near-Earth asteroid, called Bennu. While there, it will collect a sample to bring back to Earth for study. But how exactly do we plan to get this spacecraft there and bring the sample back?

Here’s the plan:

After launch, OSIRIS-REx will orbit the sun for a year, then use Earth’s gravitational field to assist it on its way to Bennu. In August 2018, the spacecraft’s approach to Bennu will begin.

The spacecraft will begin a detailed survey of Bennu two months after slowing to encounter the asteroid. The process will last over a year, and will include mapping of potential sample sites. After the selection of the final site, the spacecraft will briefly touch the surface of Bennu to retrieve a sample.

To collect a sample, the sampling arm will make contact with the surface of Bennu for about five seconds, during which it will release a burst of nitrogen gas. The procedure will cause rocks and surface material to be stirred up and captured in the sampler head. The spacecraft has enough nitrogen to allow three sampling attempts, to collect between 60 and 2000 grams (2-70 ounces).

In March 2021, the window for departure from the asteroid will open, and OSIRIS-REx will begin its return journey to Earth, arriving two and a half years later in September 2023.

The sample return capsule will separate from the spacecraft and enter the Earth’s atmosphere. The capsule containing the sample will be collected at the Utah Test and Training Range.

For two years after the sample return, the science team will catalog the sample and conduct analysis. We will also preserve at least 75% of the sample for further research by scientists worldwide, including future generations of scientists.

The Spacecraft

The OSIRIS-REx spacecraft is outfitted with some amazing instruments that will help complete the mission. Here’s a quick rundown:

The OCAMS Instrument Suite

PolyCam (center), MapCam (left) and SamCam (right) make up the camera suite on the spacecraft. These instruments are responsible for most of the visible light images that will be taken by the spacecraft.

OSIRIS-REx Laser Altimeter (OLA)

This instrument will provide a 3-D map of asteroid Bennu’s shape, which will allow scientists to understand the context of the asteroid’s geography and the sample location.

OSIRIS-REx Thermal Emission Spectrometer (OTES)

The OTES instrument will conduct surveys to map mineral and chemical abundances and will take the asteroid Bennu’s temperature.

OSIRIS-REx Visible and Infrared Spectrometer (OVIRS)

This instrument will measure visible and near infrared light from the asteroid. These observations could be used to identify water and organic materials.

Regolith X-Ray Imaging Spectrometer (REXIS)

REXIS can image X-ray emission from Bennu in order to provide an elemental abundance map of the asteroid’s surface.

Touch-and-Go Sample Arm Mechanism (TAGSAM)

This part of the spacecraft will be responsible for collecting a sample from Bennu’s surface.

Watch Launch and More!

OSIRIS-REx Talk Wednesday, Sept. 7 at noon EDT Join us for a discussion with representatives from the mission’s science and engineering teams. This talk will include an overview of the spacecraft and the science behind the mission. Social media followers can ask questions during this event by using #askNASA. Watch HERE.

Uncovering the Secrets of Asteroids Wednesday, Sept. 7 at 1 p.m. EDT During this panel, our scientists will discuss asteroids, how they relate to the origins of our solar system and the search for life beyond Earth. Social media followers can ask questions during this event by using #askNASA. Watch HERE.