'Contact binary' comet 67P/Churyumov-Gerasimenko is proving to be an odd duck

Friday, July 18, 2014, 4:25 PM - The Rosetta spacecraft is getting closer to its rendezvous with 67P/Churyumov-Gerasimenko these days, and the pictures it has been sending back are showing that the comet is a bit of an 'odd duck' - in more ways than one.

67P/Churyumov-Gerasimenko is still way out by Jupiter's orbit, so it doesn't look like your typical comet, simply because the Sun's radiation there isn't strong enough to make it produce the hazy coma and the gaseous tail. This has allowed the European Space Agency's Rosetta spacecraft to snap some excellent images of it, and it will eventually allow the spacecraft to land a probe on the comet's surface, without having to deal with the same problems it would if the comet was more active.

Now that Rosetta is within about 12,000 kilometers of 67P/Churyumov-Gerasimenko, setting up for an August 6th encounter, it snapped several photos in succession, showing the comet tumbling through space. Amazingly, what was thought to be one distinct object has turned out to be what they are calling a 'contact binary' - two icy snowballs that orbit each other, but are joined at the hip, so to speak.

Here's how the comet looked on July 11th, 2014:

The latest images, from just three days later, show off 67P/Churyumov-Gerasimenko's details even better, and this animated image shows how it's rotating.

After looking at the images, though, Alex Parker, a planetary astronomer at the University of California - Berkeley, had a different take on the comet's classification, though.

.@elakdawalla Contact binary? Anvil? Boot? No, the morphology is clear: Churyumov-Gerasimenko is a rubber duckie. pic.twitter.com/AqtsXqQtVj

— Alex Parker (@Alex_Parker) July 15, 2014

Rosetta is less than three weeks away from its rendezvous with 67P/Churyumov-Gerasimenko. As it gets closer, it will begin to alter its path, so that it will actually go into orbit around the comet (the first spacecraft ever to do so). Once it achieves orbit, it will then land a small probe, called Philae, will descend to the surface, becoming the first human-made object to land on a comet. 67P/Churyumov-Gerasimenko's unusual shape will certainly make that more challenging than the ESA team likely thought it would be, but after 10 years of effort on this mission, they're not going to let that deter them.

You can check out more information on Rosetta, Philae and 67P/Churyumov-Gerasimenko on the ESA's website (click here).

(Image credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)