[meteorite-list] NASA Sends EPOXI on Mission to Comet Hartley 2

[Ron Baalke]

Dec. 13, 2007

Grey Hautaluoma 
Headquarters, Washington
202-358-0668
grey.hautaluoma-1 at nasa.gov

DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle at jpl.nasa.gov

Nancy Neal
Goddard Space Flight Center, Greenbelt, Md.
301-286-0039
nancy.n.jones at nasa.gov

Lee Tune
University of Maryland, College Park 
301-405-4679
ltune at umd.edu

RELEASE: 07-279

NASA SENDS SPACECRAFT ON MISSION TO COMET HARTLEY 2

WASHINGTON - NASA has approved the retargeting of the EPOXI mission 
for a flyby of comet Hartley 2 on Oct. 11, 2010. Hartley 2 was chosen 
as EPOXI's destination after the initial target, comet Boethin, could 
not be found. Scientists theorize comet Boethin may have broken up 
into pieces too small for detection.

The EPOXI mission melds two compelling science investigations -- the 
Extrasolar Planet Observation and Characterization and the Deep 
Impact Extended Investigation. Both investigations will be performed 
using the Deep Impact spacecraft. 

In addition to investigating comet Hartley 2, the spacecraft will 
point the larger of its two telescopes at nearby exosolar planetary 
systems in late January 2008 to observe several previously discovered 
planetary systems outside our solar system. It will study the 
physical properties of giant planets and search for rings, moons and 
planets as small as three Earth masses. It also will look at Earth as 
though it were an exosolar planet to provide data that could become 
the standard for characterizing these types of planets.

"The search for exosolar planetary systems is one of the most 
intriguing explorations of our time," said Drake Deming, EPOXI deputy 
principal investigator at NASA's Goddard Space Flight Center, 
Greenbelt, Md. "With EPOXI we have the potential to discover new 
worlds and even analyze the light they emit to perhaps discover what 
atmospheres they possess." 

The mission's closest approach to the small half-mile-wide comet will 
be about 620 miles. The spacecraft will employ the same suite of two 
science instruments the Deep Impact spacecraft used during its prime 
mission to guide an impactor into comet Tempel 1 in July 2005. 

If EPOXI's observations of Hartley 2 show it is similar to one of the 
other comets that have been observed, this new class of comets will 
be defined for the first time. If the comet displays different 
characteristics, it would deepen the mystery of cometary diversity.

"When comet Boethin could not be located, we went to our backup, which 
is every bit as interesting but about two years farther down the 
road," said Tom Duxbury, EPOXI project manager at NASA's Jet 
Propulsion Laboratory in Pasadena, Calif.

Mission controllers at JPL began directing EPOXI towards Hartley 2 on 
Nov. 1. They commanded the spacecraft to perform a three-minute 
rocket burn that changed the spacecraft's velocity. EPOXI's new 
trajectory sets the stage for three Earth flybys, the first on Dec. 
31, 2007. This places the spacecraft into an orbital "holding 
pattern" until time for the optimal encounter of comet Hartley 2 in 
2010. 

"Hartley 2 is scientifically just as interesting as comet Boethin 
because both have relatively small, active nuclei," said Michael 
A'Hearn, principal investigator for EPOXI at the University of 
Maryland, College Park. 

EPOXI's low mission cost of $40 million is achieved by taking 
advantage of the existing Deep Impact spacecraft. 

JPL manages EPOXI for NASA's Science Mission Directorate, Washington. 
The spacecraft was built for NASA by Ball Aerospace & Technologies 
Corp., Boulder, Colo.

For information about EPOXI, visit:

http://www.nasa.gov/epoxi

	
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