Astronomy / Astrophysics

The center of the Milky Way seen in detail by the MWA radio telescope

Three articles published in the journal “Publications of the Astronomical Society of Australia (PASA)” report some results of the GaLactic and Extragalactic All-sky MWA (GLEAM) survey. A team of researchers created some images obtained thanks to the Murchison Widefield Array (MWA) radio telescope showing the center of the Milky Way. Thanks to the low-frequency radio emissions detected, it was possible to generate an image that reproduces both the larger structures and the details. This means that it was possible to obtain an overall image and images of individual objects such as 27 supernova remnants.

The afterglow of GRB 190114C observed by Hubble (Image NASA, ESA, and V. Acciari et al. 2019)

Three articles published in the journal “Nature” report different aspects of the study of a gamma-ray burst cataloged as GRB 190114C which was observed at many frequencies in what’s called multiband observation. Many scientists, particularly the ones from the MAGIC Collaboration, combined observations made using space and ground-based telescopes to study the gamma-ray burst with the greatest energy ever observed. In fact, photons were detected with an energy of the order of the teraelectronvolt, a level theorized for a long time but only now confirmed. A fourth article to be published in the journal “Astronomy and Astrophysics” reports an analysis of the galaxy in which GRB 190114C occurred.

An investigation on multiple star systems shows that many of them host planets

An article published in the journal “Monthly Notices of the Royal Astronomical Society” reports an analysis of data collected by ESA’s Gaia space probe in search for exoplanets in multiple systems. Dr. Markus Mugrauer of the University of Jena, Germany, examined over 1,300 stars hosting exoplanets in a radius of about 1,600 light years from Earth to determine which of them had one or even more companions. The result is that over 200 of them are multiple systems, in one case even a quadruple one, in which the companions are above all red dwarfs but in eight cases there’s a white dwarf as a companion. This is the confirmation that multiple systems with exoplanets are not an exception and that exoplanets can survive the death of one of the stars.

Asteroid Ryugu (Photo courtesy JAXA, Chiba Institute of Technology, University of Tokyo, Kochi University, Rikkyo University, Nagoya University, Meiji University, University of Aizu, AIST)

The Japanese space agency JAXA has confirmed that its Hayabusa 2 space probe has left asteroid Ryugu, reached on June 27, 2018. Until November 19 it will keep on taking pictures of Ryugu, a limit due to the fact that subsequently a maneuver needed to use its ion engine will lead it to turn into a position from which it will no longer have the asteroid in its camera’s view. Until that day, it will be possible to send a farewell message to Ryugu via Twitter or even letters and postcards to JAXA. Hayabusa 2 is scheduled to return near the Earth with its samples near the end of 2020.

The image of an ancient galaxy multiplied by a gravitational lens

An article published in the journal “Science” reports a study of a galaxy nicknamed Sunburst Arc observed through a gravitational lensing effect that leads to multiplying its image obtaining at least 12 distorted copies in four large arcs. The Hubble Space Telescope detected the light from that galaxy, about 11 billion light years from Earth, thanks to that effect, which also made it between 10 and 30 times brighter. Studying such an ancient galaxy allows to gather information on the early universe and on what’s called the epoch of reionization.