
NASA’s OSIRIS-REx Spacecraft Enters Close Orbit Around Bennu - sohkamyung
https://www.asteroidmission.org/?latest-news=nasas-osiris-rex-spacecraft-enters-close-orbit-around-bennu-breaking-record
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saagarjha
> The spacecraft entered into orbit around the asteroid Bennu, and made Bennu
> the smallest object ever to be orbited by a spacecraft.

You can’t say that and not tell us how small Bennu is! From Wikipedia, it
seems like it’s about half a kilometer wide.

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imglorp
> If the spacecraft drifts away from Bennu, or some other problem forces it
> into safe mode, it has been programmed to fly away from the asteroid to stay
> safe from impact.

> “It’s simple logic: always burn toward the Sun if something goes wrong”

I see the requirement to avoid a collision while in safe mode, but how is
burning sunward always the safest direction?

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dnadler
It looks like the probe might be in a polar orbit, and it may also be the case
that the plane of the orbit is perpendicular to the sun, so burning sunward
would always be safe.

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tempodox
What a fascinating project. I wonder, however: If the asteroid is so flimsy,
might the spacecraft's maneuvers influence or even destabilize its orbit?

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isostatic
It still masses a million tons more than the orbiting probe

Gravity is tiny - 1/100,000th of that of earth. Escape velocity is about
20cm/second, so don’t stand up quickly!

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bdamm
Why no closeups?

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sohkamyung
See the Gallery [1] for imagery.

[1] [https://www.asteroidmission.org/galleries/spacecraft-
imagery...](https://www.asteroidmission.org/galleries/spacecraft-imagery/)

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bdamm
Wow!!

