August 2019

Representation of the jet of a gamma-ray burst such as GRB 190114C (Image courtesy Kitty Yeung)

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An article published in “The Astrophysical Journal Letters” reports a study on a gamma-ray burst cataloged as GRB 190114C and detected by NASA’s Swift satellite and the MAGIC telescopes at the Canaries. Professor Evgeny Derishev and Professor Tsvi Piran put together the data from these detecions, which are about photons at very different energies, concluding that the radiations detected must have originated in a jet that moved at a speed of about 99.99% of the speed of light. These are so-called ultra-high energy emissions in the Teraelettronvolt (TeV) range and they think that the mechanism of origin is the inverse Compton scattering while emissions of less energetic photons originate from synchrotron radiation.

The Gl 357 system (Image NASA's Goddard Space Flight Center/Chris Smith)

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An article published in the journal “Astronomy & Astrophysics” reports the discovery of three exoplanets in the system of the red dwarf GJ 357. A team of researchers led by Rafael Luque of the Canary Islands Astrophysics Institute identified the innermost exoplanet, named GJ 357 b, thanks to the observations conducted by NASA’s TESS space telescope while the other two, named GJ 357 c and GJ 357 d, were discovered using the radial velocity method thanks to data collected over twenty years of observations of various ground-based telescopes. The three exoplanets could all be rocky and the outermost is within ​​its star system’s habitable zone.