We are about half way there. A comet turns out to be a mass of frozen methane, water, and carbon dioxide and related molecules. This clearly will lack internal strength and easily break up as we well know from observed comets tightly orbiting the sun at perihelion. What this does explin is the genesis of comet dust.
As the comet passes close the the Sun, its temperature rises sharply, and all the surface will experience temperatures well over the heat of molecular disassociation. All this will free an enormous amount of elemental carbon which will pick up static charge and push away from the bulk of the comet itself. This is formed on the way around and out from the comet. That fresh halo will stay largely with the comet throughout the rest of its orbit and is significant enough absorb enough charge on the inward pass to form a highly visible tail.
I do not expect this carbon dust to easily reaccrete anywhere along the orbit but to be mostly lost on each passage through the sun's own plasma halo. Thus a comet is slowly broken up and powdered until it can be absorbed by the sun. This can take a log time.
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Presence of Organic Molecules on the Comet it Landed On
Researchers hope the finding sheds light on how organic molecules might have first arrived on Earth
By Rachel Nuwer
smithsonian.com
http://www.smithsonianmag.com/smart-news/philae-spacecraft-confirmed-presence-organic-molecules-comet-it-landed-180953379/
scientists have confirmed the presence of organic compounds—the building blocks of life—in the atmosphere of comet 67P/Churyumov-Gerasimenko, the Wall Street Jouranl reports. The exact composition of the molecules is still being determined.
Researchers have long hypothesized that comets helped to seed the Earth with the organic material necessary for life to form. In August, the Rosetta probe detected several organic molecules in the comet's gaseous wake, including water, carbon monoxide, carbon dioxide, ammonia, methane and methanol, the Journal writes. But this is the first time, the Guardian adds, that we've been able to directly sample a comet directly for the presence of complex compounds. Studying which molecules are present and attempting to determine how they form can potentially lend insight into the history of life on our own planet.
scientists have confirmed the presence of organic compounds—the building blocks of life—in the atmosphere of comet 67P/Churyumov-Gerasimenko, the Wall Street Jouranl reports. The exact composition of the molecules is still being determined.
Researchers have long hypothesized that comets helped to seed the Earth with the organic material necessary for life to form. In August, the Rosetta probe detected several organic molecules in the comet's gaseous wake, including water, carbon monoxide, carbon dioxide, ammonia, methane and methanol, the Journal writes. But this is the first time, the Guardian adds, that we've been able to directly sample a comet directly for the presence of complex compounds. Studying which molecules are present and attempting to determine how they form can potentially lend insight into the history of life on our own planet.
Scientists had originally hoped to sample both the comet's atmosphere and soil before Philae's batteries died last Friday, the Guardian reports. But Philae's drill encountered an exceptionally hard surface. The team thinks the comet's surface is not solid rock but is simply frozen.
The hope is that, as 67P/Churyumov-Gerasimenko approaches the sun in the coming months, it will begin to thaw. At the same time, the Guardian continues, Philae's solar panels can harvest the energy needed to get the drills running and sample the surface.
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