Rosetta spacecraft cosies up to Comet 67P on Valentine's Day for extreme closeup pictures
Tuesday, February 17, 2015, 6:21 PM - Rosetta, the ESA's comet explorer, snapped some incredible images over the weekend, giving us its closest view ever of the surface of Comet 67P/Churyumov–Gerasimenko.
The European Space Agency changed things up a bit last week with their Rosetta spacecraft, adjusting its orbit around Comet 67P to get a long-view. On Saturday, Feb 14, Rosetta swung in close, flying by the comet at just 6 kilometres above the surface.
For a little bit of scale, that's well below the altitude that commercial jetliners cruise at when they're ferrying people on cross-continental flights, so anyone who's looked out the window during such a flight has seen the Earth from further away than Rosetta was at closest approach!
What did this accomplish? See for yourself!
These first two images were taken on the way in, as Rosetta 'dive bombed' towards the surface of the rotating comet, giving a look at the small lobe of the comet and the region known as Hatmehit (the depression in the middle) from 35 km out, and then the large lobe from 10.6 km above the surface.
After that, as it was just under 9 km from the surface, it snapped this incredible view.
The four snapshots that have been stitched together to form this composite were taken while the spacecraft had the Sun at its back - a 'zero phase' angle, as the ESA scientists call it. This allowed for maximum illumination of the surface features, and the details that came out were stunning.
Of particular interest in this composite - the incredible variety of terrain evidenced in just this portion of the comet, and specifically the smooth, dust-covered terrain of the Imhotep region, to the upper left, and the 33-m-wide boulder Cheops towards top-centre.
According to the ESA Rosetta blog, this extreme close flyby also allowed the spacecraft's instruments to get samples from the innermost part of the comet's early coma (its atmosphere, essentially). Scientists can use this information to compare and contrast with what they're seeing of the coma from a distance, to better understand what's going on with the comet. It will obtain some its farthest-out images, at least of this portion of its mission, today (Feb 17) as it reaches an orbital distance of 255 kilometres before swinging back in.
This new orbital path is anything but simple, though. Rather than smooth elliptical orbits, the spacecraft is making a series of sharp turns to put it in the right position for these amazing views, as shown in the video below.
Source: ESA Rosetta blog