[meteorite-list] JPL Navigators Guide NEAR To Historic Landing On Asteroid Eros

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 09:41:10 2004
Message-ID: <200102132200.OAA04934_at_zagami.jpl.nasa.gov>

MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov

Contacts: JPL/ Martha Heil (818) 354-0850
       Applied Physics Lab/Helen Worth (240) 228-5113
       Mike Buckley (240) 228-7536

FOR IMMEDIATE RELEASE February 13, 2001

JPL NAVIGATORS GUIDE NEAR TO HISTORIC LANDING ON ASTEROID EROS

       With fingers flying across calculator keypads as new guidance data
flowed in, JPL space navigators yesterday used fast math, and lots of it, to
help carefully nudge NASA's NEAR Shoemaker spacecraft to its historic
touchdown on the surface of asteroid Eros.

       The success of the landing, and the spacecraft's continuing
communications with controllers via NASA's JPL- managed Deep Space Network,
astounded even the most optimistic of scientists and engineers associated
with the mission.

       "Unbelievable," was how deputy navigation team chief Jim Miller of
JPL described the landing and the fact that the spacecraft is still alive
and communicating with Earth.

       NEAR Shoemaker project managers at Johns Hopkins University's Applied
Physics Lab (APL) in Laurel, Md., reported today that the team is assessing
the overall health and performance of the spacecraft and evaluating ways to
gather additional information from the craft. A decision on how to do that
could be reached as early as today, mission managers said.

       Eros is about the size of Manhattan Island. NEAR Shoemaker landed on
a rock-strewn plain of the asteroid at 12:02:10 Pacific Standard Time
(3:02:10 EST) on Monday, Feb. 12. It had slowed to a gentle 1.9 meters per
second (4 miles per hour) just before finally coming to rest after a journey
of 3.2 billion kilometers (2 billion miles).

       Cheers and congratulations filled the NEAR Shoemaker mission
operations center at Maryland's APL yesterday as images and engineering data
arrived from the spacecraft. APL built the spacecraft and manages the
mission for NASA.

       The NEAR Shoemaker navigation team at JPL is headed by Bobby Williams
and includes Miller, Bill Owen, Mike Wang, Cliff Helfrich, Peter Antreasian
and Steve Chesley. JPL's Dr. Donald Yeomans serves as the mission's radio
science principal investigator, and JPLers Jon Gorgini and Alex Konopliv are
team members.

       The last image from NEAR Shoemaker was snapped a mere 120 meters (394
feet) from the asteroid's surface and covers an area 6 meters (20 feet)
wide. As NEAR Shoemaker touched down, it began sending a beacon, assuring
the team that the small spacecraft had landed gently. The signal was
identified by radar science data, and about an hour later was locked onto by
NASA's Deep Space Network antennas, which will monitor the spacecraft until
Feb. 14.

       NEAR Shoemaker's final descent started with an engine firing at 7:31
a.m. PST (10:31 a.m. EST), which nudged the spacecraft toward Eros from
about 16 miles (26 kilometers) away. Then four braking maneuvers brought the
spacecraft to rest on the asteroid's surface in an area just outside a
saddle-shaped depression, Himeros. When it touched down, NEAR Shoemaker
became the first spacecraft ever to land, or even attempt to land, on an
asteroid. The success was sweetened by the fact that it was not designed as
a lander.

       The spacecraft spent the last year in a close-orbit study of asteroid
433 Eros, a near-Earth asteroid that is currently 316 million kilometers
(196 million miles) from Earth. During that time it collected 10 times more
data than originally planned and completed all its science goals before
attempting its descent to the asteroid.

       For mission updates, images and other information, see
http://near.jhuapl.edu .

       JPL, a NASA center, is a division of the California Institute of
Technology in Pasadena.

                                    #####
Received on Tue 13 Feb 2001 05:00:58 PM PST