4 June, 2013
Alphasat has its solar arrays installed at Astrium, ready for shipment to its launch location at Kourou, French Guiana.
A still from an animation showing the deployment of Gaia’s sunshade. During launch, the 10 m-wide sunshield is stowed against the spacecraft. Shortly after Gaia separates from its launch vehicle, the sunshield is deployed around the base of the spacecraft. It consists of 12 long rectangular panels covered with multilayer insulation blankets, and 12 triangular sections to fill in the gaps.
The shield has two purposes: to shade Gaia’s sensitive telescopes and cameras, keeping them cool at a stable temperature below –100ºC, and to provide power to operate the spacecraft. Gaia will always point away from the Sun, so the underside of the skirt is covered with solar panels to generate electricity.
Looking towards the constellation of Triangulum (The Triangle), in the northern sky, lies the galaxy pair MRK 1034. The two very similar galaxies, named PGC 9074 and PGC 9071, are close enough to one another to be bound together by gravity, although no gravitational disturbance can yet be seen in the image. These objects are probably only just beginning to interact gravitationally.
Both are spiral galaxies, and are presented to our eyes face-on, so we are able to appreciate their distinctive shapes. On the left of the image, spiral galaxy PGC 9074 shows a bright bulge and two spiral arms tightly wound around the nucleus, features which have led scientists to classify it as a type Sa galaxy. Close by, PGC 9071 — a type Sb galaxy — although very similar and almost the same size as its neighbour, has a fainter bulge and a slightly different structure to its arms: their coils are further apart.
The spiral arms of both objects clearly show dark patches of dust obscuring the light of the stars lying behind, mixed with bright blue clusters of hot, recently-formed stars. Older, cooler stars can be found in the glowing, compact yellowish bulge towards the centre of the galaxy. The whole structure of each galaxy is surrounded by a much fainter round halo of old stars, some residing in globular clusters.
Gradually, these two neighbours will attract each other, the process of star formation will be increased and tidal forces will throw out long tails of stars and gas. Eventually, after maybe hundreds of millions of years, the structures of the interacting galaxies will merge together into a new, larger galaxy.
The images combined to create this picture were captured by Hubble's Advanced Camera for Surveys (ACS). A version of this image was submitted to the Hubble’s Hidden Treasures image processing competition by Judy Schmidt.
These pictures give the first detailed views of the next batch of Galileo satellites, the first of which has already been delivered to ESA for rigorous testing in simulated space conditions.
The first Galileo Full Operational Capability (FOC) satellite was delivered to ESA’s ESTEC technical centre in Noordwijk, the Netherlands on 15 May.
It is being prepared for testing in the ESTEC Test Centre, a unique facility for Europe with all the facilities needed to validate a satellite for launch under one roof.
ESA astronaut Luca Parmitano spent six months on the International Space Station conducting experiments and keeping the orbital outpost running with five colleague astronauts.
In Luca’s spare time he photographed our world from 400 km high, looking out of the Station’s panoramic Cupola. Luca tweeted the picture above with the comment: “The sky is simply perfect.” Of course, for people living down below, the weather would have been described as “patchy, with sunlight coming through at times”.
Orbiting at 28 800 km/h, Luca was privileged to see our planet from a unique perspective. Here, Earth’s curvature is clearly visible, with the thin layer of pale blue atmosphere separating us from the harshness of space.
To see more of Luca's incredible shots, please visit the Volare mission Flickr channel.
The recently launched Proba-V miniaturised satellite captured this image over the border region of northern Syria, southeastern Turkey and northern Iraq on 28 May 2013. The area pictured is about 500 km across, with large reservoir lakes along the Euphrates River visible on the left, and another along the Tigris River on the right. In the central-right portion of the image, we can see Iraq’s Sinjar mountains. Proba-V will map land cover and vegetation growth across the entire planet every two days with its Vegetation imager. In this image, the contrast between the green areas – some with agricultural plots – and the sparsely vegetated areas is evident. It demonstrates Proba-V’s ability to see slight differences in vegetation cover. Vegetation intensity and health can help in crop yield predictions and to map interannual changes in vegetation cover.
This image is featured on the Earth from Space video programme.
Week In Images
24-28 June 2013