rosetta and comet
January 25, 2014

Countdown Is On For March Activation Of Rosetta Instruments

redOrbit Staff & Wire Reports - Your Universe Online

The countdown is on for the instruments on the European Space Agency (ESA) Rosetta spacecraft, as the ultraviolet imaging spectrograph, a microwave thermometer and a plasma analyzer are scheduled to be activated in early March, NASA announced on Friday.

Rosetta, which woke up Monday following a 31-month deep space slumber, is scheduled to become the first spacecraft to orbit a comet and land a probe on its nucleus in November. The vehicle’s primary scientific instruments are scheduled to begin operations in August, according to the US space agency.

“US scientists are delighted the Rosetta mission gives us a chance to examine a comet in a way we've never seen one before – in orbit around it and as it kicks up in activity,” said Claudia Alexander, Rosetta project scientist at the Jet Propulsion Laboratory (JPL). “The NASA suite of instruments will provide puzzle pieces the Rosetta science team as a whole will put together with the other pieces to paint a portrait of how a comet works and what it's made of.”

The objective of the Rosetta mission is to conduct up-close observations of the comet 67P/Churyumov-Gerasimenko. The spacecraft will be examining the full composition of the comet’s nucleus as well as the ways in which a comet evolves. Scientists are hoping to use the information it collects in order to learn more about our solar system’s origins and evolution, as well as the role comets may have played in providing the Earth with water and maybe even life.

“The ultraviolet imaging spectrograph, called Alice, will analyze gases in the tail of the comet, as well as the coma, the fuzzy envelope around the nucleus of the comet,” NASA explained. “The coma develops as a comet approaches the sun. Alice also will measure the rate at which the comet produces water, carbon monoxide and carbon dioxide. These measurements will provide valuable information about the surface composition of the nucleus.”

Alice will also be measuring the amount of argon present in the comet, which could provide important insight into the temperature of the solar system 4.6 billion years ago (when its nucleus originally formed).

The Microwave Instrument for Rosetta Orbiter will be identifying chemicals on or near the comet’s surface. It will also be measuring the temperature of the chemicals and the ice and dust shooting out from the comet, and will be observing gaseous activity in the tail through coma.

Finally, the five individual instruments that comprise the spacecraft’s Ion and Electron Sensor will be analyzing the comet’s plasma environment. It will be focusing on the coma, and will measure the charged particles in the solar wind as they interact with gas being given off by the comet as Rosetta nears its nucleus.

“NASA also provided part of the electronics package the Double Focusing Mass Spectrometer, which is part of the Swiss-built Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) instrument,” the agency said. “ROSINA will be the first instrument with sufficient resolution to separate two molecules with approximately the same mass: molecular nitrogen and carbon monoxide.”

“Clear identification of nitrogen will help scientists understand conditions at the time the solar system was born,” NASA added. US science investigators are also collaborating on several international instruments, and are playing a role in seven of the Rosetta mission’s 21 instrument collaborations. The agency’s Deep Space Network is also supporting the ESA’s Ground Station Network for spacecraft tracking and navigation.

Rosetta, which is comprised of both an orbiter and a lander, will be traveling beyond the main asteroid belt and will obtain the first-ever images captured from the surface of a comet. Furthermore, it will be providing the first-ever analysis of a comet’s composition by drilling into its surface, and will also become the first to observe up-close how a comet changes in response to the increasing intensity of the sun's radiation.

The spacecraft will be capturing its first images of the comet 67P/Churyumov-Gerasimenko in May, when it is still 1.2 million miles away from its target. At the end of that month, it will perform a critical maneuver in order to get itself in line to rendezvous with the comet, and it will follow that up with two months of extensive mapping of the comet’s surface. It will also begin collecting data about the comet at that time.