When theRosetta spacecraftarrived at 67P / C - G last spring , it saw the famed comet kick out around 100 kilo ( 220 quid ) of junk . On the surface , the probe could see strange , orbitual holes . It seemed as though these holes were responsible for the plumes of junk through the collapse of surface fabric , but Rosetta researcherDennis Bodewits , from theUniversity of Maryland , explains that something else seems to be at work .
" When we do the math , it sour out that these holes are too big . If you calculate the amount of material that comes out of such a hole , that would be a much bigger burst than what we saw , " he tell IFLScience .
So , Bodewits and fellow put two and two together and alternatively predicted that the pit were the result of something go on beneath the control surface : sinkholes similar to those on Earth .
What the squad predicts could be occurring is that upstanding water , trap under the control surface of the comet , warms up ( maybe as it approaches the sun ) and turns straight to vapor . This forms a hole under the surface of the comet , and when it gets big enough , the control surface collapses , form these circular features .
When the water turn from deoxyephedrine to vapor , it skips the liquid stage : " comet are extremely cold : they have a lot of ice in their Interior Department . And these comets are also in the vacancy of space , so the body of water live straight from ice to evaporation : It ’s a process called sublimation , " Bodewits explains .
Fortunately for the team , Rosetta can get a good peek at the sides and bottoms of these hole , lead to some interesting observations . For model , some of the sinkholes were as deep as they were broad , whereas others were shallow . The team even recognize gas add up from the side of the deeper ones .
" The shallow ones are plausibly an old adaptation of the deeper I , " Bodewits said . Over time , they ’ve been partly occupy in with dust and junk .
Your thinking might turn to thePhilae landerthat is now sitting on the comet ’s surface . Being swallow by a sink , especially after its harrowing landing , would just be too tragic . Fortunately , there is niggling probability of Philae falling into a surprisal sinkhole . " You only find sinkholes in specific places on the comet , and that was an important result by itself because it mean that the Interior Department is not homogenous . For whatever reason , some parts of the surface are unlike that others . fortuitously for Philae , there are no sink holes where he is now , " said Bodewits .
There is the possibleness that it is n’t water that ’s have these sinkholes to emerge . " We do n’t really get laid what comet are made of . We have a good clue : There ’s CO ( carbon paper monoxide ) and CO2(carbon dioxide ) ; there ’s water . But in the final stage , we can only see what comes out of the comet , " he explains .
This is what is so swell about these cavities : They give scientists an otherwise unsufferable window into the surface of the comet . And if we could somehow peer further into these holes and examine what ’s at the bottom , we may be able to learn about the comet ’s subsurface structure . Bodewits thinks that we could attach this research together with analysis of other comets to help us predict the organization of our solar system .
The whole squad is rhapsodic that the Rosetta project has been stretch forth into the summer of next year . " To really succeed a comet into an prolonged part of its orbit and see how it changes , is just a treasure trove , " he said .
[ Via Nature , University of Maryland ]
