Rosetta’s Comet Has a Shiny Necklace

New pictures show a bright “neck” where the comet’s two pieces join.

comet 67p july 2014.jpg
Comet 67P etc., as seen from a distance of 3,400 miles on July 20. Note the brighter pixels around the middle.

As Europe’s Rosetta spacecraft closes in on the comet called 67P/Churyumov-Gerasimenko (man, is that thing crying out for a nickname), the object’s shape is coming into focus, literally. Pictures taken earlier this month showed that 67P is a “contact binary,” most likely formed when two lumps of space rock or rubble collided and stuck together to form one lump. Carsten Güttler of the Max-Planck-Institute for Solar System Research, where Rosetta’s OSIRIS camera was built, was quoted saying that the comet’s nucleus “looks a bit like a rubber duck, with a body and a head.” His colleagues must have liked the description, because they’ve taken to calling the area between the nucleus’s two lobes the “neck.”

Closer pictures taken last weekend show that the neck appears brighter, and may be made of a different material or have a different topography than the rest of the nucleus. Scientists have seen this kind of smooth-in-the-middle appearance before, notably in a comet called Hartley 2 that was visited by the EPOXI spacecraft in 2010.

We’ll soon solve the mystery: Rosetta is due to rendezvous with 67P on August 6.

Rosetta’s Comet Has a Shiny Necklace
Comet 67P as seen from a distance of about 7,500 miles on July 14. This movie is made from 36 OSIRIS images, taken 20 minutes apart.