Stars

Artist's concept of ultra-short-period exoplanet and its star (Image NASA’s Goddard Space Flight Center / TESS / MIT / Lincoln Laboratory)

An article accepted for publication in “The Astronomica Journal” describes the discovery of a planet that orbits EPIC 228732031, a star just a little smaller than the Sun. A team of researchers used NASA’s Kepler space telescope to detect traces of the transits of the exoplanet that was called EPIC 228732031b. This type of discovery has become common but in this case it’s a super-Earth whose orbit is very close to its star, so much that its year only lasts 8.9 hours.

The galaxy NGC 4993 seen from several different ESO telescopes (Image VLT/VIMOS. VLT/MUSE, MPG/ESO 2.2-metre telescope/GROND, VISTA/VIRCAM, VST/OmegaCAM)

Yesterday ESO and LIGO/VIRGO collaboration held a press conference to present the results of a complex research that led to the discovery of the merger of two neutron stars observed in the emission of both electromagnetic and gravitational waves. These findings were collected in a series of articles that were published or will be published in the magazines “Nature”, “Nature Astronomy”, “Astrophysical Journal Letters” and “Physical Review Letters”.

The supernova MUSSES1604D (Image courtesy Institute of Astronomy, the University of Tokyo)

An article published in the journal “Nature” describes a research that provides evidence that the explosion of a supernova was triggered by the detonation of a helium layer on the surface of a white dwarf. A team of researchers led by Ji-an Jiang of the University of Tokyo used the Subaru telescope with follow-up observations using the Gemini-North telescope to study MUSSES1604D, a type Ia supernova. Their conclusion is that a white dwarf stole helium from a companion star and it formed a layer that at one point exploded, triggering the supernova.

Illustration of the possible dust cloud around Tabby's star (Image NASA/JPL-Caltech)

An article published in “The Astrophysical Journal” describes a research that offers an explanation of the many sudden brightness changes observed in Tabby’s star in recent years. A team of researchers co-ordinated by the University of Arizona used data collected by NASA’s Spitzer and Swift space telescopes and the Belgian AstroLAB IRIS observatory concluding that this phenomenon is caused by a dense cloud of dust orbiting the star.

V766 Cent and its companion (Image ESO/M. Wittkowski (ESO))

An article accepted for publication in the journal “Astronomy & Astrophisics” describes a study on the star V766 Cent, also known as the HR 5171 A, the largest yellow hypergiant discovered so far. A team of researchers used ESO’s Very Large Telescope Interferometer (VLTI) to conduct new observations and compare them to the previous ones. The observation of the evolution of V766 Cent is made more complicated by the fact that a companion passes in front of it.