Rosetta spacecraft

Mission Deep Impact In July 2005, NASA steered a projectile, about 370 kg in weight, at the comet 9F/Tempel (dimensions 4x4x14km), in order to obtain more exact information on its structure and composition. The impact was visible from Earth the Rosetta spacecraft discussed above also sent pictures to Earth. The dust/ice ratio determined after the impact is very probably greater than unity, so that comets are probably icy dustballs rather than (as had previously been surmised) dirty snowballs . The density of the cometary nucleus, which seems to consist of porous material, is roughly equal to that of ice. The impact set free around 19 GJ of... 

Artist s rendering ofAnny-Chantal Levasseur-Regourd after leaping off the Rosetta spacecraft onto Comet 67P/Churyumov-Gerasimenko to collect dust samples. Courtesy of F. Castel. 

Philae landing site selection process, the flight dynamics requirements of the Rosetta spacecraft and the comet s thermal and solar illumination conditions also had to be taken into account. The location chosen as the primary landing site for Philae was on the top of the smaller lobe of the comet. 

Fig. 4. Comet CG/67P 500 million km from Earth, 18 km from the Rosetta spacecraft in the field of view of the CIVA panorama camera aboard Philae still aboard Rosetta (left), and by the Rosetta navigation camera...

The starting times and duration of the radio visibility time-windows for the Rosetta spacecraft to establish a radio link with the Philae lander depended on numerous circumstances and factors, such as the executed flight track of the Rosetta spacecraft, the 12.6 hours rotation period of the comet, the landing site, and the orientation of Philae on the comet. Although these time-windows were nominally calculable, Philae had to be prepared also for the worst-case, if there was any deviation fi-om the predictions. 

The Central On-Board Computer of the Philae Lander in the Context of the Rosetta Space Mission. Andras Baldzs, from the Wigner Research Centre for Physics in Budapest, Hungary, presented an overview of the major hardware and software design aspects of the central on-board computer of the Philae lander, which traveled over 10 years as the precious payload of the Rosetta spacecraft that recently made the historical encounter with the comet 67P/Churyumov-Gerasimenko. 

European planetary missions such as the Rosetta spacecraft in 2003, the Mars Express in 2003, and the BepiColombo Mercury planetary orbiter planned for July 2016... 

Although the most recent and presumably best analytical results from meteorites do indicate the presence of an excess of L-amino acids, the results obtained thus far are not conclusive for many scientists. Once a meteorite or dust particle enters our environment, it is exposed to a system in which L-amino acids dominate. The amount of amino acids found on meteorites is very small, and how can we be sure that that the system has not been contaminated Perhaps the answer to this question will have to wait until the year 2014. This is when the robotic lander Philae will detach itself from the orbiter of the Rosetta spacecraft and land on the comet 67P/Chur5nimov-Gerasimenko [8]. Some fairly sophisticated chemistry will be performed in order to separate and analyze the organic compounds that are discovered. One of these experiments will be to determine the chirality of the compounds that are detected. Maybe then we will know whether our region of space is producing an excess of L-amino acids, (see Sidebar 3.B). 

The Rosetta Mission. The Rosetta spacecraft with the lander Philae is the first spacecraft to include an experiment to detect chiral molecules outside our planet. The spacecraft was named in honor of the Rosetta stone, which allowed Egyptian hierogl5q>hics to be translated, and resulted in... 

In the future, we expect to see many more radio astronomy spacecraft experiments. Spacecraft experiments will allow the submillimeter spectral range to be observed without hindrance from the terrestrial atmosphere. Planetary spectroscopy in the submillimeter spectral range is expected to reveal new information about the upper atmospheres of the planets. The ESA ROSETTA spacecraft... 

Stern s research has taken him to the South Pole, to a number of major astronomical observatories, and to the upper atmosphere aboard high-performance military aircraft. His areas of interest include spacecraft rendezvous theory, terrestrial polar mesospheric clouds, galactic astrophysics, and tenuous satellite atmospheres. He has been principal investigator for a number of space projects, including the European Space Agency s Rosetta/ ALICE Extreme Ultraviolet Spectrometer Experiment (a mission to study Comet 46P/Wirtanen), two Space Shuttle projects, three airborne research projects, and two research rocket projects. In 1995, Stern was selected to be a Space Shuttle Mission Specialist finalist for a forthcoming flight. 

NASA s most recent comet missions are Deep Impact and Rosetta. Deep Impact was launched on January 12, 2005, with Comet Tempel 1 as its target. The spacecraft encountered Tempel 1 on July 3, 2005, at which time it released a 770-pound (350 kg) copper projectile at the comet. Cameras and spectrometers on the spacecraft photographed and collected samples of materials ejected from the comet nucleus and relayed that information to scientists on Earth. Rosetta was launched on March 2, 2004, with Comet 67P/Churyumov-Gerasimenko as its target. The spacecraft will orbit the comet and make observations for about two years as the comet approaches the Sun. It will also release a small package of instruments that make the first-ever landing on the surface of a comet. 

---