January 2019

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.

Evidence of methane rains on Saturn's great moon Titan's north pole

An article published in the journal “Geophysical Research Letters” reports evidence of rainfall on Titan, the largest of Saturn’s moons. A team of researchers led by Rajani Dhingra, a doctoral student in physics at the University of Idaho, examined images captured by the Cassini space probe, finding an anomaly at the north pole of Titan interpreted as a methane rain. This is an indication of the beginning of summer in this moon’s northern hemisphere.

New estimates of Saturn's characteristics include the age of its rings

An article published in the journal “Science” describes a research on the planet Saturn that includes an analysis of its internal structure but also on its evolution, which includes its rings’. A team of researchers led by Luciano Iess of the Sapienza University of Rome, Italy, used data collected by the Cassini space probe to determine that the winds on Saturn reach a depth of about 9,000 kilometers and that the rings were formed not more than 100 million years ago.

A rare hypernova shows the possible death of a very massive star

An article published in the journal “Nature” reports the observation of a gamma-ray burst (GRB) cataloged as GRB 171205A associated with a supernova cataloged as SN 2017iuk that was tens of times brighter than that type of event generally is, so as to fall into the category of hypernovae. A team of astronomers led by Luca Izzo of the Instituto de AstrofĂ­sica de AndalucĂ­a (IAA-CSIC) detected for the first time interaction between the jet that caused the GRB and the outer layers of the exploded star. This allowed to better understand the mechanisms that combine hypernovae and gamma-ray bursts, connected to a “hot cocoon”.

SN 2015 cp is a rare type Ia supernova

An article accepted for publication in “The Astrophysical Journal” reports the discovery of a type Ia supernova, cataloged as SN 2015 cp. A team of astronomers led by Melissa Graham of the University of Washington used observations made with the Hubble Space Telescope and others to study a binary system in which a star that could be a red giant ejected huge amounts of materials and a part reached its companion, a white dwarf, causing its explosion.