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Philae (previously known as RoLand) is the name of the lander that accompanies the Rosetta spacecraft. It is designed to land on a comet (67P/Churyumov-Gerasimenko) shortly after arrival. ^{[1] [2]}

Contents 1 Design 2 Instruments 3 External links 4 References

The lander is designed to touch down on the comet’s surface after detaching itself from the main spacecraft body and “falling” towards the comet along a ballistic trajectory. It also will deploy harpoons to anchor itself to the surface, and the legs are designed to dampen the initial impact to avoid bouncing. Communications with Earth will use the orbiter spacecraft as a relay station to reduce the electrical power needed on board the Lander. The mission duration on the surface is planned to be at least one week, but an extended mission that lasts months is possible.

The main structure of the Lander is made from carbon fiber, shaped into a plate maintaining mechanical stability, a platform for the science instruments, and a hexagonal “sandwich” to connect all the parts. The total weight of the Lander is about 100 kg. Its “hood” is covered with solar cells for power generation.

The higher mass and therefore stronger gravitational force of the new target comet 67P/Churyumov-Gerasimenko compared to 46P/Wirtanen made changes in the landing gear necessary.^[3]

• APXS (Alpha Proton X-ray Spectrometer) APXS analyses the the chemical element composition of the surface below the lander. The instrument is a improved version of the APXS of the pathfinder mission on mars.
• COSAC (The COmetary SAmpling and Composition) The combined gas chromatograph and time of flight mass spectrometry will perform analysis of soil samples and determin the content of volatile components.^[4]
• Ptolemy ^[5][6]
• ÇIVA
• ROLIS (Rosetta Lander Imaging System)
• CONSERT (COmet Nucleus Sounding Experiment by Radio-wave Transmission)
• MUPUS (MUlti-PUrpose Sensors for Surface and Sub-Surface Science)
• ROMAP (Rosetta Lander Magnetometer and Plasma Monitor)
• SESAME (Surface Electrical, Seismic and Acoustic Monitoring Experiments)
• SD2 (The sampling, drilling and distribution subsystem)

• Rosetta website
• Rosetta Lander an article by Andrew J Ball, 1997.
• Philae site at gwdg.de
• Experiments German page with all onboard experiments.

1. ^ S. Ulameca, S. Espinasseb, B. Feuerbachera, M. Hilchenbachc, D. Mourad, H. Rosenbauerc, H. Scheuerlea, R.Willneckera (2006). "Rosetta Lander—Philae: Implications of an alternative mission". Acta Astronautica 58: 435 – 441. DOI:10.1016/j.actaastro.2005.12.009. 
2. ^ J. Biele (2002). "The Experiments Onboard the ROSETTA Lander". Journal Earth, Moon, and Planets 90 (1-4): 445-458. DOI:10.1023/A:1021523227314. 
3. ^ Ulamec S, Espinasse S, Feuerbacher B, Hilchenbach M, Moura D, Rosenbauer H, Scheuerle H, Willnecker R (2006). "Rosetta Lander - Philae: Implications of an alternative mission". Acta Astronautica 58 (8): 435-441. 
4. ^ Gosmann F., Rosenbauer H., Roll R., Bohnhardt H. (2005). "COSAC onboard Rosetta: A bioastronomy experiment for the short-period comet 67P/Churyumov-Gerasimenko". Astrobiology 5 (5): 622-631. 
5. ^ Wright, I. P.; Barber, S. J.; Morgan, G. H.; Morse, A. D.; Sheridan, S.; Andrews, D. J.; Maynard, J.; Yau, D.; Evans, S. T.; Leese, M. R.; Zarnecki, J. C.; Kent, B. J.; Waltham, N. R.; Whalley, M. S.; Heys, S.; Drummond, D. L.; Edeson, R. L.; Sawyer, E. C.; Turner, R. F.; Pillinger, C. T. (2006). "Ptolemy – an Instrument to Measure Stable Isotopic Ratios of Key Volatiles on a Cometary Nucleus". Space Science Reviews. DOI:10.1007/s11214-006-9001-5. 
6. ^ D. J. Andrews, S. J. Barber, A. D. Morse, S. Sheridan, I. P. Wright, G. H. Morgan, (2006). "Ptolemy: An Instrument aboard the Rosetta Lander Philae, to Unlock the Secrets of the Solar System.". Lunar and Planetary Science XXXVII: 1937. 

v • d • e Asteroid Spacecraft
Flybys: Galileo | NEAR Shoemaker | Deep Space 1 | Stardust | New Horizons | Rosetta probe
Orbiters: NEAR Shoemaker | Hayabusa | Rosetta probe
Landers: NEAR Shoemaker (end of mission) | Minerva mini-lander (failed) | Philae lander
Future: Dawn Mission