[meteorite-list] EPOXI on Final Approach Towards Comet Hartley 2

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue, 2 Nov 2010 17:21:03 -0700 (PDT)
Message-ID: <201011030021.oA30L371013087_at_zagami.jpl.nasa.gov>

http://www.jpl.nasa.gov/news/news.cfm?release=2010-367

NASA Spacecraft on Final Approach Toward Comet
Jet Propulsion Laboratory
November 02, 2010

The EPOXI mission spacecraft has refined its path toward a Nov. 4 flyby
of comet Hartley 2, successfully performing its final maneuver today at
8 a.m. PDT (11 a.m. EDT). The spacecraft burned its engines for 6.8
seconds, changing the spacecraft's velocity by 1.4 meters per second (3
miles per hour).

"I've worked the Stardust flyby of comet Wild 2 and the Deep Impact
encounter with comet Tempel 1, and I have never seen a comet flit around
the sky like this one," said mission navigator Shyam Bhaskaran of NASA's
Jet Propulsion Laboratory in Pasadena, Calif. "We needed to make this
burn to re-locate the spacecraft for the 700-kilometer [about 435 miles]
flyby distance."

Part of the reason Hartley 2 is hard to pin down is because the small
comet is very active.

"Hartley 2 is one-seventh the size of comet Tempel 1, but it releases
almost the same amount of material into the space environment," said
EPOXI Principal Investigator Mike A'Hearn of the University of Maryland.
"These jets can act as thrusters and actually make small changes to the
comet's orbit around the sun."

On Thursday, Nov. 4, the spacecraft will fly past the comet, with
closest approach expected about 7 a.m. PDT [10 a.m. EDT]. This flyby
will mark the fifth time in history that a spacecraft has been close
enough to image the heart of the comet, more commonly known as the nucleus.

EPOXI is an extended mission that uses the already "in-flight" Deep
Impact spacecraft to explore distinct celestial targets of opportunity.
The name EPOXI itself is a combination of the names for the two extended
mission components: the extrasolar planet observations, called
Extrasolar Planet Observations and Characterization (EPOCh), and the
flyby of comet Hartley 2, called the Deep Impact Extended Investigation
(DIXI). The spacecraft will continue to be referred to as "Deep Impact."

JPL, a division of the California Institute of Technology in Pasadena,
manages the EPOXI mission for NASA's Science Mission Directorate,
Washington. The University of Maryland, College Park, is home to the
mission's principal investigator, Michael A'Hearn. Drake Deming of
NASA's Goddard Space Flight Center, Greenbelt, Md., is the science lead
for the mission's extrasolar planet observations. The spacecraft was
built for NASA by Ball Aerospace & Technologies Corp., Boulder, Colo.

For more information about EPOXI, visit: http://www.nasa.gov/epoxi and
http://epoxi.umd.edu/.

Priscilla Vega/DC Agle 818-354-1357/393-9011
Jet Propulsion Laboratory, Pasadena, Calif.
Priscilla.r.vega at jpl.nasa.gov / agle at jpl.nasa.gov

2010-367
Received on Tue 02 Nov 2010 08:21:03 PM PDT