May 2021

Comet C/2016 R2 (PANSTARRS) and its spectrum (Image ESO/L. Calçada, SPECULOOS Team/E. Jehin, Manfroid et al.)

0

Two articles published in the journal “Nature” report different studies on the materials present in the atmospheres of comets, which appear to contain iron and nickel even in the ones far from the Sun. Jean Manfroid, Damien Hutsemekers, and Emmanuel Jehin used data collected by the UVES spectrograph of ESO’s VLT in Chile to analyze the atmospheres of various comets detecting the presence of both iron and nickel. Piotr Guzik and Michał Drahus used the X-shooter spectrograph, also of the VLT, to examine in particular the interstellar comet 2I/Borisov detecting the presence of nickel. They were surprising results because the sublimation of heavy metals was thought possible only near the Sun.

An infographic that illustrates the statistics of exoplanets with the radius gap and the possible mechanisms that make mini-Neptunes shrink until they turn into super-Earths

0

An article published in “The Astronomical Journal” reports a study on the scarcity of exoplanets with a radius between 1.5 and 2 times the Earth’s. A team of researchers led by Trevor David of the Flatiron Institute in New York studied what is commonly referred to as a radius gap using data collected by NASA’s Kepler Space Telescope. By dividing the exoplanets studied between those older than 2 billion years and those younger, the exam offers new information confirming the theory that sub-Neptunes can lose most of their atmosphere and transform into super-Earths even after billions of years.

Schematical representation of the expansion of the Universe over the course of its history (Image courtesy NAOJ)

0

An article published in “The Astrophysical Journal” reports a calculation of the expansion velocity of the universe based on type Ia supernovae. A team of researchers led by Professor Maria Giovanna Dainotti used a sample of 1048 supernovae that have very different distances from Earth, dividing them into groups based on their distance. The values ​​obtained are decreasing starting from the nearest supernovae, and those obtained using the most distant supernovae approach the value based on the cosmic microwave background radiation.

TOI-269 seen by TESS

0

An article accepted for publication in the journal “Astronomy & Astrophysics” reports the confirmation by a team of researchers led by Marion Cointepas of the exoplanet TOI-269 b, a sub-Neptune orbiting a red dwarf discovered thanks to NASA’s TESS space telescope. It’s a warm Sub-Neptune because its year only lasts 3.7 Earth days, as it’s very close to its star. It’s not the first case of that type, but this is interesting because estimates of its characteristics indicate that it’s close to the boundaries between sub-Neptunes and super-Earths. The loss of the atmosphere with the transformation from sub-Neptune to super-Earth is a case studied only in theory and TOI-269 b could provide useful information to understand this process.

Artist's concept of the Tianwen 1 mission's vehicles (Image courtesy CNSA / Chinese Academy of Sciences / Nature Astronomy)

0

A few hours ago the lander and rover of the Chinese Tianwen 1 mission landed successfully on the planet Mars, in the Utopia Planitia region. The event was confirmed by the Chinese space agency making China the third nation to land a vehicle on the red planet after the USA and the then USSR. The rover, which was named Zhurong, has a life expectancy of at least 90 days during which it will explore the area by making surveys with a series of instruments. The orbiter, which reached Mars together with the lander and rover on February 10, 2021, continues its work from above.