The surface ice of comet 67P and its outgassing activities follow a cycle based on the sun’s illumination on the object. #rosettaspaceprobe #comet67P #comets - http://clapway.com/2015/09/25/comet-67p-has-nights-and-days123/

The Rosetta space probe has made a new discovery regarding the water-ice cycle of comet 67P/Churmov-Gerasimenko. As it turns out, the surface ice of the comet and its outgassing activities follow a cycle based on the sun’s illumination on the object, and it is theorized that this very cycle may be used by other comets.

Maria Cristina de Sanctis, part of INAF-IAPS (Institute of Astrophysiology and Spacial Planetology at the National Institute of Astrophysics in Rome), reveals that the probe, owned by the European Space Agency, observed a process that replenishes the surface of the comet with fresh ice with every new rotation. This helps to keep the comet alive in a sense. Comets (for those who don’t know) are formations of the solar system made up of dust, rocks, and ice; they are scattered around the sun and move in their own orbits.

THE “DAY AND NIGHT” CYCLE OF COMET 67P

Using Rosetta’s Visible Infrared and Thermal Imaging Spectrometer (VIRTIS), researchers have found a one square km region of Comet 67P’s neck where this process occurs, in which the water-ice on its surface dissipates and reappears in relation to its rotational position.

How does this happen? Well, when a comet nears the sun, the heat of the giant star vaporizes its icy surface into gas in a process known as outgassing. As the ice starts to sublimate, dust and rock in the comet is released and floats away from the comet’s surface, giving the celestial body its signature halo and tail.

By contrast, when the same area is not under sunlight, the surface cools until it re-freezes and the comet is re-covered with a very thin layer of ice. The process, driven by the day/night cycle, restarts when sunlight once again glides over the comet.

“We saw the tell-tale signature of water ice in the spectra of the study region but only when certain portions were cast in shadow,” states Maria Cristina. “Conversely, when the Sun was shining on these regions, the ice was gone. This indicates a cyclical behaviour of water ice during each comet rotation.”

The findings of this study are now published in the journal Nature.

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WE MARVEL IN ALL THE WONDERS OF SPACE:

Comet 67P Has A Night And Day Cycle Too

Space Sinkhole Discovered on Comet - http://clapway.com/2015/07/02/space-sinkhole-discovered-on-comet876/

You may have heard of the economic sinkhole of the 1970’s, consuming small town banks and farming businesses alike. Okay, maybe you haven’t, but physical sinkholes rarely make the news, and we’ve certainly never witnessed one on an asteroid before. Now, it may all be seen, thanks to the Rosetta Spacecraft, the first and (currently) in standard orbit of an asteroid.

YES, SINKHOLES… IN SPACE

This is exactly what a team of University of Maryland scientists think Rosetta is seeing on the surface of comet 67p/Churyumov-Gerasimenko. The collapsed structures appear to span ten to several hundred meters in diameter. Officials suspect these kinds of sinkhole formed in ways not unlike the way they do down here, on Earth.

HOW WE CAME TO KNOW THE HOLES

Scientists initially hypothesized that major explosive events caused the sinkholes, mainly because Rosetta captured such entropic images on its approach. However, after applying the mathematical calculations to plot the path of ejected asteroid debris, scientists could see that something was amiss. In this low gravity, only sinkholes could create such dispersal patterns.

ROSETTA’S EQUIPMENT AND HOLY SHAPES

This analysis was made possible by Rosetta’s Optical, Spectroscopic and Infrared Remote Imaging System (OSIRIS) camera. The University of Maryland research team posited two types of sinkhole from their research: first are the shallow ones, not dissimilar to pits visible on other comets. But another, deeper kind of structure with sharp inclines was also noted, featuring high-pressure jets of gas and dust streaming into the darkness.

HOLY GENESIS

The running theory’s that larger pits take shape when a major heat source beneath the surface of a comet sublimates ice. In other words, the ice (a solid) suddenly or rapidly enters a phase change, transforming into gas. Such a reaction immediately removes support for any less subterranean layers, because water vapor doesn’t really stay in one place for long. After surface layers fall, a big, deep, circular pit is left for us to ogle, thanks to the sinkhole and Rosetta’s OSIRIS.

MISCELLANEOUS ROSETTA FACTS

Launched on March 2nd, 2004 from Guiana and operated by the European Space Agency, Rosetta is a robotic space probe sent to perform the most comprehensive study of a comet yet attempted. It cost roughly one billion Euros. NASA backs the University of Maryland’s participation in the program.

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Space Sinkhole Discovered on Comet