Researchers at the Caltech and NASA’s Jet Propulsion Laboratory have created a sort of comet like stuff in a cryostat. Scientists have described the average comet to be
just like a fried ice cream. Ask a kid about any fried ice cream and he will describe it in a jiffy – squishy on the interior, crusty on the outside with organic chemicals dusted on top.
The structure of the comet long speculated by the scientists have all but confirmed by Both the ESA’s Rosetta and NASA’s Deep Impact comet missions. Both the missions have found evidence of the soft, porous interiors of comets, and the Philae lander discovered the hard surface the hard way, with a triple-bounce that surprised mission scientists and degraded some of its activities.
Antti Lignell at Caltech and Murthy Gudipati of JPL explained “that the fluffy ice on the surface of a comet would crystallize and harden as the comet heads towards the sun and warms up”.
In comparison to the fluffy interior the ice crystals are denser and more orderly pushing the carbon-containing organic molecules to the surface. The interiors are composed of a form of ice which is not formed in normal conditions on Earth. The amorphous and porous forms of the ice are formed when water vapor is flash frozen at 30 degree Kelvin and never forms crystals.
To replicate the process which comets go through, Gudipati and Lignell used the Himalaya cryostat to slowly heat amorphous ice, doped with polycyclic aromatic hydrocarbons (PAHs), a common deep-space molecule, from 30 Kelvin to 150 Kelvin
Lignell explained. “The PAHs stuck together and were expelled from the ice host as it crystallized. This may be the first observation of molecules clustering together due to a phase transition of ice”.