[meteorite-list] Curiosity Rover on Track for Early August Landing

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.cfm?release=2012-220  

Curiosity Rover on Track for Early August Landing
Jet Propulsion Laboratory
July 28, 2012

Mars Science Laboratory Mission Status Report

PASADENA, Calif. -- Eight days before reaching Mars, NASA's Mars Science
Laboratory spacecraft performed a flight-path adjustment scheduled more
than nine months ago.

The trajectory correction maneuver completed late Saturday may be the
last one the mission needs before landing day, though two further
opportunities remain on its schedule in case they are needed.

The spacecraft is on course for delivering the mission's car-size rover,
Curiosity, to a landing target beside a Martian mountain at about 10:31
p.m. PDT on Aug. 5. (1:31 a.m. on Aug. 6, EDT). After landing, the rover
will spend a two-year prime mission studying whether the area has ever
offered environmental conditions favorable for life.

The spacecraft used two brief thruster firings totaling about six
seconds to adjust its trajectory at about 10 p.m. PDT on July 28 (1 a.m.
on July 29, EDT). This maneuver had been on the mission's schedule since
before launch on Nov. 26, 2011. It altered the flight path less than any
of the spacecraft's three previous trajectory correction maneuvers on
the way from Earth to Mars.

The Mars Science Laboratory spacecraft had been on a course in recent
weeks that would have hit a point at the top of the Martian atmosphere
about 13 miles (21 kilometers) east of the target entry point. On
landing day, it can steer enough during its flight through the upper
atmosphere to correct for missing the target entry point by a few miles
and still land on the intended patch of Mars real estate. The mission's
engineers and managers rated the projected 13-mile miss big enough to
warrant a correction maneuver.

"The purpose of this maneuver is to move the point at which Curiosity
enters the atmosphere by about 13 miles," said Tomas Martin-Mur of
NASA's Jet Propulsion Laboratory, Pasadena, Calif., chief of the
mission's navigation team. "The first look at telemetry and tracking
data afterwards indicates the maneuver succeeded as planned."

The thruster firings altered the spacecraft's velocity by about
one-fortieth of one mile per hour (one centimeter per second). Curiosity
will enter Mars' atmosphere at a speed of about 13,200 mph (5,900 meters
per second).

Opportunities for two further course corrections are scheduled in the
final 48 hours before landing, if needed.

"I will not be surprised if this was our last trajectory correction
maneuver," Martin Mur said of Saturday's event. "We will be monitoring
the trajectory using the antennas of the Deep Space Network to be sure
Curiosity is staying on the right path for a successful entry, descent
and landing."

Descent from the top of Mars' atmosphere to the surface will employ bold
techniques enabling use of a smaller target area and heavier landed
payload than were possible for any previous Mars mission. These
innovations, if successful, will place a well-equipped mobile laboratory
into a locale especially well-suited for its mission of discovery. The
same innovations advance NASA toward capabilities needed for human
missions to Mars.

As of July 30, the Mars Science Laboratory spacecraft carrying the rover
Curiosity will have traveled about 343 million miles (555 million
kilometers) of its 352-million-mile (567-million-kilometer) flight to Mars.

JPL, a division of the California Institute of Technology in Pasadena,
manages the mission for the NASA Science Mission Directorate,
Washington. More information about Curiosity is online at
http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/ . You can
follow the mission on Facebook at: http://www.facebook.com/marscuriosity
and on Twitter at: http://www.twitter.com/marscuriosity .

Guy Webster/D.C. Agle 818-354-6278/818-393-9011
Jet Propulsion Laboratory, Pasadena, Calif.
Guy.Webster at jpl.nasa.gov / Agle at jpl.nasa.gov

2012-220