OSIRIS-REx Recovery


On September 8, 2016, the OSIRIS-REx spacecraft was launched into space from Cape Canaveral in Florida. I was an Electrical Engineer working on the OCAMS science payload from 2012 to 2015, and I was there to watch it go!

A year later, on September 22, 2017 at 16:52 UT, it passed by the Earth in an Earth Gravity Assist (EGA) maneuver, which will send it on to its target asteroid, 101955 Bennu. It is scheduled to arrive at Bennu in August 2018.

I currently work for the Spacewatch project and observe with two telescopes on Kitt Peak near Tucson, Arizona. I was the observer for the few nights before the EGA. My goal was to spot the spacecraft, make measurements, and test the capabilities of our hardware and software. The night before closest approach, the object would be moving very fast, and quickly accelerating. In other words, it's a really close Near-Earth Object!

On a personal note, being able to recover OSIRIS-REx is quite special to me. From 2002 to 2003, I helped design and build the Mosaic CCD camera system that is still in use today at the 0.9-m telescope. Now I get to use that system to image another camera system (in space!) that I helped build and test. How awesome is that?

OSIRIS-REx was recovered on September 2, 2017 by the Large Binocular Telescope at magnitude 25, which is very faint. Assuming it gets four times brighter as it gets twice as close, I estimated it would be about magnitude 20 on September 20 UT, my first night. This is within reach of both the 0.9-m and 1.8-m telescopes.

Using the JPL Horizons website to generate an ephemeris, I was able to plan a set of recovery images.

Click on the links below to see GIF animations of each attempt.

Enjoy!

- Mike Read

mread at lpl dot arizona dot edu


The OSIRIS-REx spacecraft was recovered by Mike Read with the 0.9-m telescope of Steward Observatory on Kitt Peak on 2017 September 20, 21, and 22 UT.

2017-09-20 UT

OSIRIS-REx is the fast-moving dot to the upper-left of center.
It was measured at magnitude 19.4, and about 1.26 million kilometers from Earth.
That's over 3 times farther than the distance to the Moon!
Also visible in the field are two asteroids, moving at much slower rates.

     0.9m_20170920-005-1 - 10:00 UT - 60 sec

2017-09-21 UT

OSIRIS-REx streaking towards an asteroid (not Bennu).

     0.9m_20170921-014-1 - 07:00 UT - 120 sec

2017-09-22 UT

Passing through a nice star field near a small galaxy.

     0.9m_20170922-008-1 - 05:00 UT - 120 sec - 1 amp

     0.9m_20170922-008-2 - 05:00 UT - 120 sec - 2 amps

Star strike! Plus a few asteroids. It's moving noticeably faster than before.

     0.9m_20170922-012-1 - 07:00 UT - 120 sec - 1 amp

     0.9m_20170922-012-2 - 07:00 UT - 120 sec - 2 amps

Passing a bright star, dodging geosynchronous satellites, through some clouds.
OSIRIS-REx is the streak moving from top to bottom.
Look both ways before crossing the road!

     0.9m_20170922-018-1 - 10:00 UT - 120 sec - center

     0.9m_20170922-018-2 - 10:00 UT - 120 sec - bottom

Parting shots through some spinning satellites. Farewell!
It was 145,000 km from Earth, less than half the distance to the Moon!

     0.9m_20170922-019-1 - 11:00 UT - 240 sec



The OSIRIS-REx spacecraft was recovered by Mike Read with the 1.8-m Spacewatch telescope on Kitt Peak on 2017 September 21 and 22 UT.

2017-09-21 UT

Star field.
It was measured at magnitude 18.0, and about 0.8 million kilometers from Earth.

     1.8m_20170921-05-2 - 05:00 UT - 60 sec

2017-09-22 UT

Moving faster. Wind bounce.

     1.8m_20170922-07-2 - 05:00 UT - 120 sec


Reference:

OSIRIS-REx - asteroid sample-return spacecraft

Spacewatch - observe the sky for Near-Earth Objects