Rosetta Closes In on Comet 67P

HEARTS IN RUIN begins with a paleolithic couple facing uncertainty at the approach of the “Fire Star.” Later, they experience first hand the effects of its impact with Earth. Today, we have a much safer way to setup first-hand experience with a comet, and ESA is in the process right now of executing our new method of encountering a comet.

The International Rosetta Mission launched an unmanned spacecraft on March 2, 2004 with the express objective of intercepting comet 67P/churyumov-Gerasimenko, in August 2014 and observing it through perihelion in August 2015 and back into deep space. Upon rendezvous, the Rosetta spacecraft will enter orbit around the comet and perform observations of the comet’s nucleus and coma. When 67P/C-G reaches perihelion (the closest point to the Sun in its orbit), the resulting increase in activity will be measured. Also, a lander, named Philae, will be deployed and will attempt to make the first controlled landing on a comet.

The Rosetta design is based on a box-type central structure, 2.8 m × 2.1 m × 2.0 m, on which all subsystems and payload equipment are mounted. Two solar panels, with a combined area of 64 m², stretch out to 14 m in length. The total span from tip to tip is 32 m. The Philae lander is attached to the spacecraft side opposite to the side that carries the 2.2m diameter steerable high-gain antenna.

The Philae lander will carry a sophisticated package of instruments, including the following 10 science experiments:

APXS (Alpha Proton X-ray Spectrometer)
ÇIVA / ROLIS (Rosetta Lander Imaging System)
CONSERT (Comet Nucleus Sounding)
COSAC (Cometary Sampling and Composition experiment)
MODULUS PTOLEMY (Evolved Gas Analyser)
MUPUS (Multi-Purpose Sensor for Surface and Subsurface Science)
ROMAP (RoLand Magnetometer and Plasma Monitor)
SD2 (Sample and Distribution Device)
SESAME (Surface Electric Sounding and Acoustic Monitoring Experiment)

The spacecraft has followed a complex path, including four gravitational boosts using the gravity wells of two different planets to close in on the comet. Rosetta is now very close and pacing the comet.

Rosetta takes its name from the Rosetta Stone, an incomplete stela of black basalt incised with the same priestly decree concerning Ptolemy V, in three scripts. Although three scripts are shown (Egyptian Hieroglyphs, Egyptian Demotic and Greek) just two languages are represented. The great significance of the Stone is that it provided the key to deciphering Egyptian hieroglyphs. Scientists hope that the Rosetta mission will unlock the mysteries of how the Solar System evolved.

Comet 67P/C-G has been observed from Earth on seven approaches to the Sun – 1969 (discovery), 1976, 1982, 1989, 1996, 2002 and 2009. It is one of numerous “Jupiter Family” comets, whose orbit is controlled by Jovian gravity. These comets are believed to originate from the Kuiper Belt. When they pass Jupiter their orbits change, and they are eventually thrown out of the Solar System or collide with a planet or the Sun.

ESA’s site for the mission can be found HERE.