Proposed Visits to Martian Moons and Mercury -- Two Hopkins-Managed Missions Selected As NASA Discovery Program Candidates

The proposals -- Aladdin, designed to return samples from two Martian moons to Earth, and MESSENGER, which would orbit the planet Mercury -- were among 26 full-mission proposals submitted to NASA. Also selected was a Jet Propulsion Laboratory proposal to study the interior of Jupiter, a proposal by the University of Maryland to excavate and study material from deep inside a comet, and a proposal by NASA's Goddard Space Flight Center to explore the middle atmosphere of Venus.

Following submission of detailed mission concept studies, due by March 31, 1999, NASA intends to select one or two of the mission proposals in June 1999 for full development as the seventh and possibly eighth Discovery Program flights.

"Aladdin and MESSENGER were finalists in the previous round of Discovery Program selections in 1997, and their selection this time again confirms their technical excellence and the strength of their scientific promise," says Dr. Tom Krimigis, Head of the APL Space Department.

The Aladdin spacecraft would visit the Martian moons Phobos and Deimos in early 2003 to gather samples by firing five projectiles into the moons' surface and gathering ejecta during slow flybys. The samples, returned to Earth in January 2006, would help scientists answer fundamental questions about small bodies, remnants of the building blocks of the solar system. The Aladdin mission would be led by Dr. Carlé Pieters of Brown University, Providence, R.I. Under thedirection of Ted Mueller, APL would design the spacecraft and many of its scientific instruments, conduct integration and testing, and provide overall mission management and operations for a total cost of $247.7 million, which includes the launch vehicle.

The Mercury Surface, Space Environment, Geochemistry and Ranging mission, orMESSENGER, would be the first spacecraft to visit the closest planet to the sun in more than two decades. The spacecraft's seven instruments would study Mercury for a year beginning in September 2009, gathering data to help scientists understand the forces that have shaped it and other terrestrial planets. Planners also intend the mission to yield technology that can be transferred to robotics, medicine, oil exploration, laboratory instrumentation, and aircraftcommunications. Dr. Sean Solomon of the Carnegie Institution of Washington, Washington, D.C., would lead MESSENGER. Under the leadership of Max Peterson, APL would provide overall mission management, including spacecraft and instrument design, spacecraft assembly, and mission operations, for a total cost of $279.3 million.

APL designed, built, and is managing the first Discovery Program mission, Near Earth Asteroid Rendezvous (NEAR). Launched February 1996, the NEAR spacecraft is rapidly approaching itsJan. 10, 1999, encounter with asteroid 433 Eros for the first-ever close-range, prolonged study of an asteroid. In October 1997, APL was selected to build and manage the Discovery missionComet Nucleus Tour, or CONTOUR, a joint project with Cornell University, Ithaca, N.Y. Scheduled for launch in late June 2002, CONTOUR will fly to within 60 miles of at least three major near-Earth comets during the 2003-2008 time frame, taking images, making spectral maps, and analyzing dust flowing from the bodies to dramatically improve our understanding of comet nuclei and their diversity.

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The Applied Physics Laboratory is a not-for-profit laboratory and independent division of The Johns Hopkins University. APL conducts research and development primarily for national security and for nondefense projects of national and global significance. APL is located midwaybetween Baltimore and Washington, D.C., in Laurel, Md.