Space

ESA releases images of Rosetta's comet close encounter

ESA releases images of Rosetta's comet close encounter
Comet 67P as seen from an altitude of 8.7 km (5.4 mi) (Image: ESA/Rosetta/NavCam)
Comet 67P as seen from an altitude of 8.7 km (5.4 mi) (Image: ESA/Rosetta/NavCam)
View 6 Images
Four-image montage of comet 67P/Churyumov–Gerasimenko comprising images taken on 14 February 2015 (Image: ESA/Rosetta/NavCam)
1/6
Four-image montage of comet 67P/Churyumov–Gerasimenko comprising images taken on 14 February 2015 (Image: ESA/Rosetta/NavCam)
Comet 67P seen from an altitude of 10.6 km (6.5 mi) (Image: SA/Rosetta/NavCam)
2/6
Comet 67P seen from an altitude of 10.6 km (6.5 mi) (Image: SA/Rosetta/NavCam)
Montage of comet 67P showing lobes (Image: SA/Rosetta/NavCam)
3/6
Montage of comet 67P showing lobes (Image: SA/Rosetta/NavCam)
Comet 67P as seen from an altitude of 8.7 km (5.4 mi) (Image: ESA/Rosetta/NavCam)
4/6
Comet 67P as seen from an altitude of 8.7 km (5.4 mi) (Image: ESA/Rosetta/NavCam)
Diagram of Rosetta (Image: ESA)
5/6
Diagram of Rosetta (Image: ESA)
Artist's concept of Rosetta (Image: ESA)
6/6
Artist's concept of Rosetta (Image: ESA)
View gallery - 6 images

In a space-age game of chicken, the European Space Agency's (ESA) Rosetta probe made its closest approach to comet 67P/Churyumov–Gerasimenko last weekend. The spacecraft, which has ceased orbiting the comet due to 67P's increased activity as it approaches the Sun, came within 6 km (3.7 mi) of the surface over the Imhotep region of the larger of the comet’s two lobes, with the up close and personal maneuver taking place, appropriately enough, on Valentine's Day.

The flyby took place at 12:41 GMT on February 14, and as Rosetta carried out the maneuver it returned a series of images of the comet's layered and fractured surface. The images revealed a complicated, broken landscape mixed with smooth, dust-covered areas, boulders measuring up to tens of meters, and outlines of near-circular objects about which little is clearly understood. In addition, the close pass allowed the spacecraft's instruments to take samples of the inner regions of 67P's coma.

Rosetta has been studying 67P since it first went into orbit around the comet in August of last year. For much of that time, it was mapping the surface in anticipation of the Philae probe making the first soft landing on a comet in history. Since then, the spacecraft has been making a detailed study of the comet and its coma in hopes of gaining a better understanding of the mechanisms that shape comets as they approach the Sun.

Four-image montage of comet 67P/Churyumov–Gerasimenko comprising images taken on 14 February 2015 (Image: ESA/Rosetta/NavCam)
Four-image montage of comet 67P/Churyumov–Gerasimenko comprising images taken on 14 February 2015 (Image: ESA/Rosetta/NavCam)

According to ESA, Rosetta is about 345 million km (214 million mi) from the Sun. When 67P reaches its closest distance to the Sun on August 13, it will be 189 million km (117 million mi) away between the orbits of Earth and Mars. Because 67P is becoming more active as the Sun heats it, Rosetta has gone out of orbit and is now executing a series of flybys at altitudes from 15 to 100 km (9.3 to 62 mi).

The video below discusses the Valentine's Day flyby.

Source: ESA

Rosetta's closest encounter

View gallery - 6 images
2 comments
2 comments
Kerry Chivers
If Rosetta has stopped orbiting the comet then where did it go? Why would it stop the orbit at its most important time?
Danny Allman
@Kerry–Comet 67P has very little mass compared to larger celestial objects, and therefore its gravitational pull is tiny. Using its onboard fuel supply designed specifically to accommodate multiple maneuvers over the course of its mission, Rosetta can be commanded to cease orbiting the comet if desired. There is zero chance of the spacecraft "crashing" on 67P, due to its low gravitational pull. Hence any combination of orbit/non-orbit maneuvers can be accomplished within the mission's fuel limitations. It didn't "go" anywhere.