[meteorite-list] Rosetta to Deploy Lander on November 12

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?release=2014-326

Rosetta to Deploy Lander on November 12
Jet Propulsion Laboratory
September 26, 2014

The European Space Agency's Rosetta mission will deploy its lander, Philae, 
to the surface of comet 67P/Churyumov-Gerasimenko on Nov. 12.

Rosetta is an international mission spearheaded by the European Space 
Agency with support and instruments provided by NASA.

Philae's landing site, currently known as Site J, is located on the smaller 
of the comet's two "lobes," with a backup site on the larger lobe. The 
sites were selected just six weeks after Rosetta's Aug. 6 arrival at the 
comet, following the spacecraft's 10-year journey through the solar system.

In that time, the Rosetta mission has been conducting an unprecedented 
scientific analysis of the comet, a remnant from early in the solar system's 
4.6-billion-year history. The latest results from Rosetta will be presented 
when Philae lands, during dedicated press briefings.

The main focus to date has been to survey 67P/Churyumov-Gerasimenko in 
order to prepare for the first-ever attempt to soft-land on a comet.

The descent to the comet is passive and it is only possible to predict 
that the landing point will be within a "landing ellipse" (typically a 
few hundred yards or meters in size). For each of Rosetta's candidate 
sites, a larger area -- four-tenths of a square mile (one square kilometer) 
-- was assessed. Site J was chosen unanimously as the primary landing 
site because the majority of terrain within an area that size has slopes 
of less than 30 degrees relative to the local vertical and because there 
are relatively few large boulders. The area also receives sufficient daily 
illumination to recharge Philae and continue surface science operations 
beyond the initial 64-hour battery-powered phase.

Over the last two weeks, the flight dynamics and operations teams at ESA 
have been making a detailed analysis of flight trajectories and timings 
for Rosetta to deliver the lander at the earliest possible opportunity.

Two robust landing scenarios have been identified, one for the primary 
site and one for the backup. Both anticipate separation and landing on 
Nov. 12.

For the primary landing scenario, targeting Site J, Rosetta will release 
Philae at 08:35 UTC (12:35 a.m. PST; 9:35 a.m. Central European Time) 
at a distance of 14 miles (22.5 kilometers) from the center of the comet, 
landing about seven hours later. The one-way signal travel time between 
Rosetta and Earth on Nov. 12 will be 28 minutes and 20 seconds, meaning 
that confirmation of the landing will arrive at Earth ground stations 
at around 16:00 UTC (8 a.m. PST; 5 p.m. CET).

If a decision is made to use the backup site, Site C, separation will 
occur at 13:04 UTC (5:04 a.m. PST; 2:04 p.m. CET) at a distance of 7.8 
miles (12.5 kilometers) from the center of the comet. Landing will occur 
about four hours later, with confirmation on Earth at around 17:30 UTC 
(9:30 a.m. PST; 6:30 p.m. CET). The timings are subject to uncertainties 
of several minutes.

Final confirmation of the primary landing site and its landing scenario 
will be made on October 14 after a formal Lander Operations Readiness 
Review, which will include the results of additional high-resolution analysis 
of the landing sites conducted in the meantime. Should the backup site 
be chosen at this stage, landing can still occur on Nov. 12.

A competition for the public to name the primary landing site will also 
be announced during the week of Oct. 14.

Following the Philae landing, the Rosetta orbiter will continue to study 
the comet and its environment using 11 science instruments for another 
year as the spacecraft and comet orbit the sun together. The comet is 
on an elliptical 6.5-year orbit that takes it from beyond Jupiter at its 
farthest point, to between the orbits of Mars and Earth at its closest 
to the sun. Rosetta will accompany the comet for more than a year as they 
swing around the sun and back to the outer solar system again.

The analyses made by the Rosetta orbiter will be complemented by the measurements 
performed on the comet by Philae's 10 instruments.

Comets are time capsules containing primitive material left over from 
the epoch when the sun and its planets formed. By studying the gas, dust 
and structure of the nucleus and organic materials associated with the 
comet, the Rosetta mission should become key to unlocking the history 
and evolution of our solar system, as well as answering questions regarding 
the origin of Earth's water and perhaps even life.

Rosetta is an ESA mission with contributions from its member states and 
NASA. Rosetta's Philae lander is provided by a consortium led by the German 
Aerospace Center, Cologne; Max Planck Institute for Solar System Research, 
Gottingen; National Center of Space Studies of France (CNES), Paris; and 
the Italian Space Agency, Rome. NASA's Jet Propulsion Laboratory in Pasadena, 
California, a division of the California Institute of Technology, manages 
the U.S. participation in the Rosetta mission for NASA's Science Mission 
Directorate in Washington.

For more information on the U.S. instruments aboard Rosetta, visit:

http://rosetta.jpl.nasa.gov

More information about Rosetta is available at:

http://www.esa.int/rosetta

DC Agle/Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011/818-354-6278
agle at jpl.nasa.gov/guy.webster at jpl.nasa.gov

2014-326