Space Probes

The Atlas V 421 rocket at liftoff with the MMS space probes (Photo NASA)

A few hors ago the four MMS (Magnetospheric Multiscale Mission) spacecraft were launched atop an Atlas V 421 rocket from Cape Canaveral. After nearly two hours the spacecraft started separating from the rocket’s last stage, one at a time at intervals of about five minutes. It’s only the beginning of a complex phase of tests, deployment of their booms with the sensors and positioning of the probes in a tetrahedron configuration which will last more than five months.

The MMS mission is really ambitious because it’s based on the work of a constellation of four identical spacecraft that will operate together in a tetrahedral formation in order to make three-dimensional measurements. The purpose is to study the magnetosphere in a way more sophisticated than those previously attempted.

In particular, the space probes will study the phenomenon of the magnetic reconnection. It’s a process in highly conductive plasma in which the magnetic topology is rearranged and the magnetic energy is converted into kinetic and thermal energy and into particle acceleration.

NASA confirmed that its space probe Dawn regularly entered the dwarf planet Ceres’ orbit. It was at an altitude of about 61,000 kilometers (about 38,000 miles) when it was captured by the Ceres’ gravity. This happened yesterday but Dawn was on the hidden side of the dwarf planet when it entered its orbit. The consequence is that it took a bit before the probe reached a position where it could transmit data to Earth.

Montage of four pictures of the comet 67P/Churyumov-Gerasimenko taken by the Rosetta space probe's NAVCAM (Image ESA/Rosetta/NAVCAM)

After the flyby performed a few weeks ago, the Rosetta space probe moved away from the comet 67P/Churyumov-Gerasimenko and was able to observe its increasing activity. In late February, from a distance between 80 and 100 km (from 50 to 52 miles) its Navigation Camera (NAVCAM) instrument took several photographs that ESA processed to make the best observations of the jets of steam and dust emitted by the comet.

Picture of the dwarf planet Ceres taken by the Dawn space probe (Image NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

NASA’s space probe Dawn continues its approach to the dwarf planet Ceres. This allows to send on Earth better and better photographs with greater details of its surface. The previous images were clear enough to make it possible to see some light-colored areas and in particular a really bright one, which had puzzled scientists. A photo taken on February 19 at a distance of about 46,000 km (about 29,000 miles) shows a second bright area close to the one already identified.

Image of the SOHO space probe showing the comet C/2015 D1 (SOHO) near the Sun (Image ESA/NASA/SOHO/Hill)

The SOHO (Solar and Heliospheric Observatory) space probe has the primary purpose of keeping an eye on the Sun but when a comet passes close to our star is also useful to track its trajectory. Last week, SOHO identified a new comet because passing near the Sun it’s become bright enough to be detected.

This comet was originally called SOHO-2875 because in the course of over 19 years of mission in a collaboration between ESA and NASA this is the 2875th comet identified by the SOHO space probe. Subsequently officially named C/2015 D1 (SOHO), it survived a flyby with the Sun and may also be visible from Earth in the coming weeks.