Volume 4 Issue 5, May 2020

Exoplanetary and Solar System science lost a major figure with the sudden passing of Professor Adam Showman on 16 March 2020 at the age of 51. He was recognized as the world’s leading authority in the field of atmospheric dynamics of exoplanets.

The support of the international astronomical community to the 2030 Agenda for Sustainable Development is fundamental to advance the rights and needs of the most vulnerable groups of our global society. Among these groups are the refugees.

The Spitzer Space Telescope returned infrared images and spectra with unprecedented sensitivity and resolution, enabling the characterization of the dust-enshrouded star formation of and within galaxies. This has yielded indicators of total star formation, used as unbiased tracers of the stellar production across cosmic times.

The Curiosity rover is unveiling the persistence of habitable environments more than three-billion years ago at Gale crater, Mars. New analyses of Gale’s ancient sediments show that chemical processing of organic material occurred on a liquid-water rich and freezing early Mars.

One way for a relativistic jet to decelerate is by instabilities developing on its boundary, which are likely to be caused by continuous bombardment by stars from the host galaxy of the radio jet.

Measurements with a CubeSat gas pixel detector reveal a change in the Crab pulsar polarization after a glitch in the spin period, suggesting that starquakes alter the magnetosphere.

The Spitzer Space Telescope launched when the study of exoplanets was in its infancy, and yet it was remarkably successful in characterizing both exoplanet and brown dwarf systems through their mid-infrared emissions. This Review collates the highlights of Spitzer-based research in these fields.

Spitzer revealed the properties of luminous and ultraluminous infrared galaxies, the role of starbursts and actively accreting supermassive black holes in powering these sources and found evidence for energetic feedback on their interstellar gas and dust.

The Spitzer Space Telescope accurately measured stellar masses, ages and star formation rates for a large sample of typical galaxies at high redshifts, allowing an initial exploration of some of the key science drivers of the James Webb Space Telescope.

Sporadic E layers are unpredictable terrestrial ionospheric phenomena that can perturb telecommunication. Plasma features akin to sporadic E layers and their opposite (sporadic E rifts), never observed on Earth, were detected in the ionosphere of Mars from MAVEN data. In contrast to those observed on Earth, they are long lived and form at predictable locations.

The early Solar System might have been similar to the ringed protoplanetary disks observed by ALMA. One of the gaps, at Jupiter’s position, could be the cause of the observed dichotomy between carbonaceous and non-carbonaceous material.

A refined analysis of infrared observations of comet 67P/Churyumov–Gerasimenko from the VIRTIS instrument on board the Rosetta spacecraft has revealed the presence of aliphatic organic molecules on the comet nucleus.

A ring of maser emission seemingly expanding at 0.05 c is actually tracing the propagation of heat through the circumstellar medium around a high-mass protostar rather than subluminal motion. The heatwave is a manifestation of an accretion burst.

A soft X-ray polarimetry capability has been missing from astronomy since the late 1970s. Here a CubeSat polarimeter named PolarLight has detected the Crab nebula and pulsar in the soft X-ray band, measuring their polarized emission. PolarLight observed a pulsar glitch, with an associated polarization change.

A joint analysis of spectroastrometry and reverberation mapping observations independently measures the distance to the active galaxy nucleus 3C 273 and the value of H₀. Future observations of about 30 such sources will measure H₀ to less than 3% precision.

The pyrolysis experiments of the SAM instrument on board the Curiosity rover reconstruct the origin of organics at Gale crater. Some of them come from meteorites, but others have been formed in situ, with widespread past formation of carbonates via cryogenesis. More than 0.5 bar of CO₂ might have precipitated from the atmosphere.

A dust impact event detected by the ROSINA mass spectrometer towards the end of the Rosetta mission brings evidence of the presence of ammonium salts in comets. Ammonium salts can store enough nitrogen to explain the observed nitrogen depletion in comets and may have a role in amino acid formation.

Fragile et al. study the physics of accretion onto a neutron star from a thin accretion disk when interacting with an X-ray burst. A number of processes occur in the inner disk, including a reflexive retreat of the inner edge of the disk from the star, on the timescale of the burst.

PolarLight is the first dedicated soft X-ray polarimeter in space since the 1970s and is attempting to reopen this long-awaited window in astronomy, explain Principal Investigator Hua Feng and Ronaldo Bellazzini.