Rosetta’s Comet Stinks

ESA reports that Comet 67P/Churyumov-Gerasimenko stinks. Analysis of data sent back by Rosetta shows that the comet is made up of water, carbon dioxide, and carbon monoxide. It also contains ammonia (NH3), methane (CH4), methanol (CH3OH), formaldehyde (CH2O), hydrogen sulphide (H2S), hydrogen cyanide (HCN), sulphur dioxide (SO2), and carbon disulphide (CS2).

The perfume of 67P/C-G is quite strong, with the odour of rotten eggs (hydrogen sulphide), horse stable (ammonia), and the pungent, suffocating odour of formaldehyde. This is mixed with the faint, bitter, almond-like aroma of hydrogen cyanide. Add some whiff of alcohol (methanol) to this mixture, paired with the vinegar-like aroma of sulphur dioxide and a hint of the sweet aromatic scent of carbon disulphide, and you arrive at the ‘perfume’ of our comet.


Venus Close Up

Video Credit: ESA


Lutetia (Rosetta)Lutetia is a large main-belt asteroid about 100 kilometers in diameter (120 km along its major axis). It’s named after Lutetia, the Latin name of the city that stood where Paris now stands. Lutetia has an irregular shape and is heavily cratered. The largest impact crater is around 45 km in diameter. It has a high average density, meaning that it is made of metal-rich rock.

This picture was taken by the Rosetta spacecraft when it passed within 3,162 km  of the asteroid in July, 2010. Lutetia was the largest asteroid visited by a spacecraft until the Dawn spacecraft arrived at Vesta a year later.

Image Credit: ESA

NGC 4206

A dusty spiral in VirgoNGC 4206 is about 70 million light-years away. It was imaged as part of a Hubble survey of nearby edge-on spiral galaxies made to measure the effect that the material between the stars, called the interstellar medium, has on the light that travels through it. Astronomers have been able to map the absorption and scattering of light by the material which causes objects to appear redder to distant observers.

Image Credit:  ESA / NASA
Acknowledgement: Nick Rose

Jets from a Comet

Rosetta 20140926The four images that make up this montage of comet 67P/Churyumov–Gerasimenko were taken on 26 September by the ESA’s Rosetta spacecraft. Rosetta was about 26 km from the center of the comet. The picture shows a region of jet activity can be seen at the neck of the comet. These jets are originating from several locations. They are a product of ices sublimating and gases escaping from inside the nucleus.

The overlapping and slightly dissimilar angles of the four images in the montage are a result of the comet rotating as images were taken in the sequence (about 10° over 20 min) and the spacecraft’s movement as well.

Image Credit: ESA

Closing In On The Comet

Rosetta 20140924This is a four-image NAVCAM mosaic taken by the Rosetta spacecraft on 24 September from a distance of 28.5 km from the centre of comet 67P/C-G. The images are processed to remove some striping and fixed noise patterns.

As the spacecraft moves closer to the comet, it is harder to create accurate mosaics because of combined effect of the comet rotation between the first and last images taken in the sequence (about 10 degrees over 20 minutes), and the fact that the spacecraft has been moving (up to a couple of km).

Image Credit: ESA