Blog about planets.

Supernovae and water in rocky planets

An article published in the journal “Nature Astronomy” reports the results of a series of computer simulations conducted to better understand the mechanisms of rocky planets formation. A team of researchers concluded that there are probably two types of planetary systems: those similar to the solar system, with planets containing relatively little water, and those in which there are above all the so-called ocean planets or waterworlds. The difference may have been caused by the presence of a massive star nearby that ejected radioactive materials that have at least partially dried out the planets. This might have led to the emergence of a temperate climate on Earth.

The Mars Exploration Rover Opportunity's shadow (Image NASA/JPL-Caltech)

NASA announced the end of the existing possibilities to re-establish contacts with its Mars Rover Opportunity and consequently declared the end of its mission. Oppy, as it’s affectionately called, interrupted communications after June 10, 2018 following the global storm that covered the planet Mars with a blanket of dust that prevented it from obtaining energy from its solar panels. This extraordinary mission ends in this sad way because caused by an extrnal cause after over 15 Earth’s years in which it collected a wealth of information on Mars.

Artist's concept of protoplanet impact (Image Nasa/JPL-Caltech modified)

An article published in the journal “Nature Astronomy” describes a study about two super-Earths in the Kepler-107 star system that have similar size but very different densities that indicate a very different chemical composition. A team of researchers led by Aldo Bonomo of the Italian National Institute of Astrophysics (INAF) in Turin used the HARPS-N spectrograph installed on the Galileo National Telescope in the Canary Islands to examine the planets Kepler-107b and Kepler-107c and conclude that probably the remarkable differences between them are due to a primordial impact.

Mars Rover Curiosity and the Apollo 17's Moon Rover (Image NASA/JPL-Caltech)

An article published in the journal “Science” reports a clever use of the Mars Rover Curiosity’s accelerometers and gyroscopes to estimate the density of rocks under Gale Crater. A team of scientists examined the data collected over the years by those instruments to evaluate the gravity force where Curiosity passed, obtaining lower than expected measurements. This suggests that in that area the rocks are very porous and less compact than scientists thought.

Close-up of Saturn's rings (Image NASA/JPL-Caltech/Space Science Institute)

An article published in “The Astrophysical Journal” reports a precise measurement of the duration of the day on the planet Saturn. The lack of a solid surface with reference points and a magnetic field with unusual characteristics prevented precise measurements, but now a team of researchers led by Christopher Mankovich of the University of California, Santa Cruz, (UCSC) accomplished that feat by exploiting data collected by the Cassini space probe on the effects that the vibrations inside Saturn cause on the oscillation of its gravitational field and consequently also on the rings. The result is that the day on the planet was measured in 10 hours, 33 minutes and 38 seconds.