ESA’s Philae lander arrived on the surface of comet 67P on November 2014, when it detached from Rosetta, currently orbiting the planet.
A initial bumpy touchdown sent the lander tumbling into an unplanned location of the comet. Also, initial communication was impossible as Philae entered hibernation almost immediately.
Certainly nerve-wrecking in the beginning, the fortuitous touchdown is now seen as a blessing. As Philae restored communication with the team back home, a wealth of unexpected data started pouring in.
For starters, Philae gathered information on the geological and chemical composition of more points on the comet 67P surface than ever expected. Following, the icy object is now unveiling its secrets in more detail than ever. Thanks to Philae, scientists back on Earth discerned valuable knowledge on the composition, as well as evolutionary history of comets.
Everything they could learn was published on July 30th in the Science journal in no less than seven distinct papers.
According to Philae’s observations, comet 67P is in fact a porous body that features a homogeneous interior. Moreover, its surface brimming with organic molecules also containing molecules.
Nicolas Altobelli, scientist with the Rosetta project stated for Space.com:
“What really blows my mind is to have this combination of complementary results, allowing us at the same time to feel the surface of the comet, very locally, as if we were there, while also getting the bigger picture through the sounding of the cometary interior structure”.
The two locations that mark the touchdown spots of Philae as it detached from Rosetta were found to be distinct. One, Agilkia, is soft and in a blanket of granular material that measures 0.82 feet in depth. Abydos on the other hand is harder. The finding is surprising for the scientific team which expected that comet 67P would have a very soft surface.
Another set of images this time taken by the Infrared and Visible Analyser camera Philae is equipped with revealed the boulder-studded surface of the comet, spiced with grains of different sizes, as well as reflectivity.
As such, the blanket of grains reaches 6.5 feet in depth in some locations while it is nowhere to be seen in others.
At the time of landing, the Multi Purpose Sensors for Surface and Subsurface Science Instrument measured that the temperature during daytime varied between minus 226 Fahrenheit and minus 298 degrees Fahrenheit.
Certainly these would have increased as comet 67P is moving closer towards the sun in its orbiting pattern that takes 6.4 years to complete. On August 13, comet 67P will be the closes to the Sun.
Two more instruments on Philae, the COSAC and Ptolemy found that organic compounds are brimming on the comet’s surface, as well as around it.
COSAC detected 16 distinct organics. Four of these – methyl isocyanate, acetone, propionaldehyde, and acetamide – never been observed on comet before, nor around it.
Ptolemy’s observations unveiled a cocktail of organics, mixed with water as well as carbon dioxide.
Photo Credits: esa.int