What is black and gray and far away?

[Karlston]

What is black and gray and far away?

Scientists have released a new image of Bennu in stunning detail.

Enlarge / This global map of asteroid Bennu’s surface is a mosaic of images collected by NASA’s OSIRIS-REx spacecraft.

NASA/Goddard/University of Arizona

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What is black and gray and far away?

 

The asteroid Bennu is—and on Friday, NASA released an ultra-high resolution image of this planetary body for the first time. Go here to download full-size versions of the mosaic.

 

Scientists produced the mosaic by stitching together 2,155 images taken by the primary camera on board NASA's OSIRIS-REx spacecraft about one year ago. With a resolution of 5cm per pixel, NASA says this is the highest resolution mapping ever of a planetary body.

 

And let's be real: this is perhaps the most asteroid-looking asteroid we've ever seen. It is dark, strewn with boulders, and pretty desolate looking.

 

Scientists took all of these photos because they were looking for a safe location to send OSIRIS-REx down to grab some loose material on the surface. Last December, mission scientists selected a site in the "Nightingale" crater in the asteroid's northern hemisphere. The 140-meter wide crater is thought to be relatively young, so the regolith material is freshly exposed. Scientists hope to capture material that can provide insights about Bennu's origin and thus early conditions in the Solar System.

 

OSIRIS-REx launched in 2016 and arrived at Bennu in December, 2018. The 490-meter wide asteroid is in many ways a rubble pile, with a density of about 1,190kg per cubic meter. By way of comparison, a potato has a density of about 700kg per cubic meter, and dry gravel has about 1,500kg per cubic meter. With an average albedo of 4.4 percent, Bennu is one of the darkest objects in the Solar System.

 

The next big mission milestone comes in July, when OSIRIS-REx will swoop down to near the surface, send a blast of compressed nitrogen gas onto the asteroid, and then seek to collect dirt and dust particles kicked up. The asteroid dirt will be stored in a special canister while allowing the gas itself to escape. At a minimum, scientists hope to collect a few hundred grams of material for a return to Earth in September, 2023.

 

 

Source: What is black and gray and far away? (Ars Technica)