2023

A comparison between the systems of Wolf 1069, Proxima Centauri, and TRAPPIST-1

An article published in the journal “Astronomy & Astrophysics” reports the identification of the exoplanet Wolf 1069 b, which has a mass close to the Earth’s and orbits within its star system’s habitable zone. A team of researchers led by Diana Kossakowski of the Max Planck Institute for Astronomy used the CARMENES spectrographs mounted on the 3.5-metre telescope of the Calar Alto Observatory, Spain, to identify traces of Wolf 1069 b using the radial velocity method. This exoplanet is tidally locked with its star, which poses a problem for habitability, but its star doesn’t have powerful flares. These characteristics make Wolf 1069 b an interesting object of study.

The galaxy LEDA 2046648 together with many stars and especially galaxies seen by the James Webb Space Telescope

An image captured by the James Webb Space Telescope portrays the galaxy LEDA 2046648 immersed in a vast group of other more or less distant galaxies. Many spiral galaxies are recognizable and this is to be expected as they’re the most common type. The NIRCam instrument captured many details of LEDA 2046648 despite being over a billion light-years away from Earth, but Webb’s performance is no longer astonishing. The observation that generated this image is among those used to calibrate the NIRISS instrument, which was out of service for a couple of weeks in the second half of January 2023 but has now resumed transmitting the collected data normally.

Artist's impression of a magnetar eruption. (Image NASA's Goddard Space Flight Center)

An article published in the journal “Nature Astronomy” reports an explanation for the abrupt slowdown in the rotation of the magnetar cataloged as SGR 1935+2154 and its attribution to a sort of volcano that ejected a kind of wind into space. A team of researchers used X-ray data from ESA’s XMM-Newton space telescope and NASA’s NICER instrument to analyze changes in the magnetar. Their conclusion is that the activity of the pseudo-volcano altered the magnetar’s magnetic field, slowing down its rotation, what in jargon is called anti-glitch. That led to the beginning of radio wave emissions subsequently detected by the Chinese FAST radio telescope.

Artist's impression of a binary system containing a spider pulsar (Image NASA/Sonoma State University, Aurore Simonnet)

An article published in the journal “Nature Astronomy” reports the detection of gamma-ray eclipses in binary systems formed by a normal star or a brown dwarf that have a pulsar as a companion that is defined as a spider pulsar because they steal gas from the companion behaving like a black widow. A team of researchers used data collected over a decade by NASA’s Fermi Space Telescope to find cases in which the star passes in front of the pulsar. Seven binaries have been identified with a spider pulsar being eclipsed by its companion. This identification made it possible to measure the pulsar’s mass, a result useful to conduct tests on the theory of relativity and understand the behavior of matter in extreme conditions.

The occultation light curve of the background star caused by the passage of asteroid Chariklo captured by the James Webb Space Telescope's Near-infrared Camera (NIRCam) instrument

A stellar occultation that took place on October 18, 2022, made it possible to study asteroid Chariklo observing its rings as well, a truly peculiar feature for such a small object. A team of researchers used the James Webb Space Telescope to capture Chariklo’s passage in front of a star from Webb’s point of view. The NIRCam and NIRSpec instruments enabled images and spectrographic features of Chariklo to be obtained. In recent days, the NIRISS instrument had a software problem that blocked the transmission of the collected data but no hardware failures were found, therefore it’s possible that the data will be recovered later to complete an in-depth study of this asteroid.