Space Probes

The triple crater in the Terra Sirenum region on Mars (Image ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO)

ESA has published some new pictures taken by its Mars Express space probe that show a curious crater in the Terra Sirenum region on Mars. It’s a crater with an elongated shape having a length of about 45 kilometers (about 28 miles) and a width of approximately 24 kilometers (about 15 miles). It’s probably the result of an asteroid impact that broke up into three parts when it was still above the surface causing the triple impact of fragments that were still very close. The sedimentary deposits on the bottom of the crater suggest that in ancient times water existed in that region of Mars.

The Sun right before the first flare's peak (Photo NASA/SDO)

In recent days, NASA’s SDO (Solar Dynamics Obersavatory) space probe detected and documented 3 M-class solar flares, the class that includes the most powerful ones after the X-class, where X means “eXtreme”. The first one had its peak on April 2 at 8.02 UTC, the second one at 20.33 UTC and the third one on April 3 at 14:29 UTC.

Artist's concept comparing Mars as it is today and as it was 4 billion years ago (Image NASA’s Goddard Space Flight Center)

An article published in the journal “Science” describes a research on the atmosphere of the planet Mars that indicates the Sun’s wind and radiation as the principal culprits of the fact that today that atmosphere is so thin. A team led by Bruce Jakosky, principal investigator of NASA’s MAVEN space probe’s mission, examined the measurements of the existing gases estimating for example that 65% of argon present origininally got lost in space. This research confirms the one published in November 2015.

Arsia Mons (Image NASA/JPL/USGS)

An article published in the journal “Earth and Planetary Science Letters” describes a research about Arsia Mons, a volcano on the planet Mars. A team led by Jacob Richardson of NASA’s Goddard Space Flight Center examined high-resolution images taken by the MRO (Mars Reconnaissance Orbiter) space probe to determine that Arsia Mons was at its peak of activity about 150 million years ago and that its last activity probably ended about 50 million years ago.

Phases of the collapse at Aswan (Image ESA/Rosetta/NavCam – CC BY-SA IGO 3.0; ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA)

Two articles, one published in the journal “Nature Astronomy” and one published in the journal “Science”, describe two studies about the comet 67P/Churyumov-Gerasimenko. The first is about a cliff Aswan in the Seth region of the comet’s nucleus that crumbled. The second article is about the changes that occurred on the comet’s surface detected thanks to ESA’s Rosetta space probe between the summer of 2014 and September 2016.