Subject: OSIRIS-REx Trajectory Planning
From: Daniel Adamo <[email-masked]>
Date: Sun, 11 Sep 2016 22:49:02 -0700

ATIG Members-

The robotic sample return mission OSIRIS-REx (Origins Spectral
Interpretation Resource Identification Security Regolith Explorer) launched
as planned on 8 September 2016 at 23:05 UT.  This mission's destination is
(101955) Bennu (1999 RQ36), a carbonaceous near-Earth object (NEO) about 500
m in diameter.  Reports and details about the mission are available at
http://www.asteroidmission.org/.

Due to its on time launch, planned trajectory data for OSIRIS-REx posted 31
August 2016 to JPL's Horizons ephemeris server at
http://ssd.jpl.nasa.gov/?horizons are reasonably valid for visualization
purposes.  The attached 5-page PDF file reflects these data and contains
inertial geocentric, heliocentric, and Bennu-centered trajectory plots.

Note the fifth plot in the attachment illustrating Bennu-centered motion at
OSIRIS=REx arrival is very preliminary and subject to change as the
asteroid's gravity field and spin state are determined in this time frame.
However, the basic arrival strategy appears to involve surveying Bennu from
above its terminator with a brief dayside equatorial flyby at close range
circa 24 November 2018.  Bennu-centered positions for the fifth plot were
sampled from Horizons at hourly intervals.

-Dan