It’s not that we know nothing about Churyumov-Gerasimenko, or Comet 67P. We know it’s been looping around the Sun every 6.5 years for billions of years. It was discovered in 1969, is about two miles across and spins on its own axis every 12 hours. And of course, it was discovered by two astronomers with really long names.
Last month, the ESA’s Rosetta spacecraft made history when it became the first spacecraft to orbit a comet. The spacecraft has eleven instruments on-board to study 67P, and “Alice” is one of three made and designed by NASA.
Comet 67P: Alice’s job
Alice isn’t taking pictures so much as hi-res UV images that we can’t take from Earth. While “Alice” has been mapping the comet since orbit was obtained, today is the first day that results have been shared.
“Alice” is a technological marvel at less than nine pounds of weight and using only four watts to power herself. NASA suggests that she has over 1,000 times the capability that an instrument similar to her would have had less than a decade ago.
After analysis, Comet 67P has surprised scientists with its dark color, darker than a slate black. The “coma” around it contains both hydrogen and oxygen but surprisingly very little ice.
“We’re a bit surprised at just how unreflective the comet’s surface is and how little evidence of exposed water-ice it shows,” said Alan Stern, an Alice investigator from the Southwest Research Institute in Boulder, Co.
To understand comets is to understand Earth
NASA’s additional instrumentation will study the composition of the comet’s coma as well as analyze its plasma content.
“As the mission progresses, we will continue to search for surface ice patches and ultraviolet color and composition variations across the surface of the comet,” said Dr. Lori Feaga, an Alice investigator at the University of Maryland.
In November, the Rosetta will once again make history when its Philae Lander becomes the first craft to actually land on a comet.
Many scientists believe that it was comets that brought water and perhaps with it life to Earth.