Date: December 14th 2007

Dec 13, 2007

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

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

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

Lee Tune University of Maryland, College Park 301-405-4679 ltune@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

-end-

To subscribe to the list, send a message to: hqnews-subscribe@mediaservices nasa gov To remove your address from the list, send a message to: hqnews-unsubscribe@mediaservices nasa gov

The following information is a reminder of your current mailing list subscription:

You are subscribed to the following list: [list_name]

using the following email: example@example.com

You may automatically unsubscribe from this list at any time by visiting the following URL:

http://www aus-city com/cgi-bin/dada/mail cgi/u/[list]/

If the above URL is inoperable, make sure that you have copied the entire address Some mail readers will wrap a long URL and thus break this automatic unsubscribe mechanism

You may also change your subscription by visiting this list's main screen:

http://www aus-city com/cgi-bin/dada/mail cgi/list/[list]

If you're still having trouble, please contact the list owner at: