Blogs about stars

The first Earth-sized exoplanet identified thanks to the TESS space telescope

An article published in “The Astrophysical Journal Letters” reports the discovery of two exoplanets in the orange star HD 21749’s system, one of which is the first Earth-sized identified thanks to NASA’s TESS space telescope and the other a Mini-Neptune. A team of researchers led by Diana Dragomir already submitted a first version of the article on the exoplanet HD 21749b, the Mini-Neptune also referred to as TOI 186.01, mentioning as candidate TOI 186.02 the rocky exoplanet now referred to as HD 21749c in the new version of the article in which it’s considered confirmed.

Artist's concept of a planetesimal orbiting the white dwarf SDSS J122859.93+104032.9 (Image courtesy University of Warwick/Mark Garlick)

An article published in the journal “Science” reports the discovery of what’s probably a fragment of a planet that orbits a white dwarf. A team of researchers led by the British University of Warwick used the Gran Telescopio Canarias of La Palma to study the debris disk that surrounds the white dwarf cataloged as SDSS J122859.93+104032.9 detecting anomalies in the emission lines that have been interpreted as the result of the presence of what has been called a planetesimal orbiting the star in about two hours.

A solution to the mystery of the origin of long gamma-ray bursts

An article published in the journal “Nature Communications” offers a solution to the problem of the origin of photons that make up a long duration gamma-ray burst. A team of researchers coordinated by the Riken Cluster for Pioneering Research in Japan created a series of simulations based on the Yonetoku relation, an equation devised by Daisuke Yonetoku, one of the authors of the research, which links the peaks of energy and brightness in gamma-ray bursts concluding that their photons originate in the photosphere, the area of ​​a star in which normal light is emitted.

A giant molecular cloud in which massive stars are forming studied with the SOFIA flying telescope

The SOFIA flying telescope was used to study a giant molecular cloud that is a star-forming area cataloged as W51 in order to analyze the newly formed or still forming stars within it. The researchers combined the observations made with SOFIA with those made over time with NASA’s Spitzer and Herschel space telescopes to obtain more complete information on those stars. There was a particular interest in the massive stars and one of them seems really huge, with a mass estimated at about 100 times the Sun’s. If that estimate is confirmed by follow-up observations it’s one of the most massive stars in formation in the Milky Way.

The galaxy MACS0416_Y1 seen by ALMA and Hubble (Image ALMA (ESO/NAOJ/NRAO), NASA/ESA Hubble Space Telescope, Tamura, et al.)

An article published in “The Astrophysical Journal” describes a study on the galaxy MACS0416_Y1. A team of researchers led by Professor Yoichi Tamura of the Japanese University of Nagoya used the ALMA radio telescope to observe a galaxy we see as it was about 13.2 billion years ago. The surprising discovery is the considerable amount of interstellar dust present within it, explained by two intense periods of star formation that took place around 300 million and 600 million years after the Big Bang with a quiet phase between them.