During the past weekend, ESA’s space probe Rosetta has taken a new flyby about 14 kilometers (about 8.6 miles) away from the comet 67P/Churyumov-Gerasimenko. This means that it hasnt come as close as in February, however, the comet’s increasing activity caused some problems in Rosetta. Among the consequences, it had serious difficulties in communicating with ESA’s mission control.
An article published in the journal “Astronomy & Astrophysics” describes the results of a research carried out by combining the observations made with ESA’s Herschel and Planck space telescopes. The purpose was to find protoclusters, the precursors of today’s galaxy clusters seen in the distant past when the universe was only three billion years. This will help to understand how these huge groups of tens, hundreds and even thousands of galaxies formed and evolved.
A combined use of the Hubble and Chandra space telescopes allowed to conduct a study of dark matter and the results were described in an article published in the journal “Science”. Currently we have no instruments to directly detect dark matter so scientists have to study it indirectly through its effects, in this case on 72 galaxy clusters to study their behavior.
The second of the two satellites of the Galileo constellation launched into a wrong orbit on August 22, 2014 has been recovered. In mid-January a series of 14 maneuvers was started that altered its orbit until it became the same as its “twin” after about six weeks. Now these two satellites have a mirror orbit, on opposite sides of the planet.
The Hubble Space Telescope has been used to study Ganymede, the largest Jupiter’s moon, and in particular its aurorae. Analyzing their characteristics, it was possible to get the best clues found so far of the existence of a Ganymede underground ocean of liquid salt water. This ocean may contain more water than it exists on the surface of the Earth.