April 2018

The supernova SN 2001ig

An article published in “The Astrophysical Journal” describes the detection of a companion of the type IIb supernova known as SN 2001ig. A team of astronomers used the Hubble Space Telescope to discover the first case of a binary system in which one of the stars survived when its partner exploded into a supernova. The two stars were not just close but there was an interaction that had an influence on the supernova.

The SPT2349-56 proto-cluster (Image ESO/ALMA (ESO/NAOJ/NRAO)/Miller et al.)

Two articles, one published in the journal “Nature” and one in the journal “Astrophysical Journal”, describe the observations of the merger among various starburst galaxies, characterized by a remarkable production of stars. Two teams, led by Tim Miller of Dalhousie University in Canada and Yale University in the USA, and Iván Oteo of the Scottish University of Edinburgh used the ALMA and APEX radio telescopes to study these events which are very ancient as they happened about 1.5 billion years after the Big Bang.

The Sentinel-3B satellite blasting off atop a Rockot rocket (Photo ESA - S. Corvaja)

A few hours ago the Sentinel-3B satellite, part of the GMES / Copernicus program, was launched from the Russian Plesetsk Cosmodrome on a Rockot launch vehicle. After about an hour and a half it separated from the rocket’s last stage, called Breeze KM, it started communicating with the control center and to deploy its solar panels. Its final orbit is Sun-synchronous, which means it will pass over a certain area of ​​the Earth at the same local time, with an altitude of about 815 kilometers (about 506 miles).

Gaia's sky DR2 map (Image ESA/Gaia/DPAC)

ESA has published the second 3D map of the Milky Way and neighbouring galaxies obtained from the Gaia space probe, the most detailed of this type ever produced. This catalog, built thanks to what was called Data Release 2 (DR2), greatly expands the first map released by ESA in September 2016.

The Gaia space probe was launched on December 19, 2013 with the aim of creating a highly accurate 3D map of the Milky Way’s stars but also to catalog billions of other celestial objects, not only stars but also galaxies. Gaia began its scientific activity in July 2014, the first map included data collected until September 2015, the DR2 includes the following 8 months of observations.

The Lagoon Nebula at visible light (Image NASA, ESA, and STScI)

On April 24, 1990, the Hubble Space Telescope was launched on the Space Shuttle Discovery and put into orbit the next day. To celebrate the 28th anniversary of that event, which represents a milestone in the history of astronomy, new breathtaking photos of the Lagoon Nebula have been published.

About 4,000 light years away from the Earth, the Lagoon Nebula was first cataloged by the astronomer Giovanni Battista Hodierna and later included in other catalogs, so much so that it’s known by various designations including Messier 8 or M8, NGC 6523, Sharpless 25, RCW 146, and Gum 72. In optimal conditions it’s visible even to the naked eye, so it’s the object of observations by amateur astronomers as well.