Volume 4 Issue 7, July 2020

eROSITA, a new X-ray telescope currently performing an all-sky survey of unprecedented depth, aims to provide insights into dark energy, dark matter, black holes and perhaps new phenomena that have so far been invisible.

The space and planetary science community lost a great leader, Professor Weixing Wan, on 20 May 2020, aged 62. He was a world-leading space scientist and a pioneer in China’s planetary science programme.

On 3 May 2020 the Greek and extended international astronomy community lost Professor Emeritus John Hugh Seiradakis, a highly impactful, wide-reaching researcher and educator, and mentor to generations of students.

A recent trial of distributed peer review for telescope time allocation at the European Southern Observatory echoes the findings of a similar scheme in place at Gemini Observatory since 2015, with both procedures reducing the time invested, financial costs and reviewer burden.

Lyman-α blobs are spatially extended nebulae of hydrogen line emission that may hold clues for understanding the formation and evolution of massive galaxies at high redshifts. Recent observations and simulations suggest that multiple mechanisms can explain the origin of these objects, notably including gravitational cooling radiation.

2M1510 is an approximately 45-million-year-old triple system of brown dwarfs, two of which form a close binary in a 20-day orbit and have almost the same mass (3.82% and 3.75% of the mass of the Sun, respectively). Their physical parameters are in good agreement with evolutionary models except for luminosity, suggesting that we might be underestimating the masses of brown dwarfs and massive exoplanets by about 30%.

Uniform analysis of both main-sequence and evolved, post-main-sequence stars shows that a common, turbulence-dependent, dynamo mechanism operates throughout these stages of stellar evolution.

A massive white dwarf (WD) with unusually low hydrogen and helium abundances, undetectable oxygen and high C/H poses a challenge to single-star evolution models. However, this object fits with expectations of a WD–WD merger product.

The gas kinematics within a Lyman-α blob show clear evidence of infall, consistent with the release of gravitational accretion energy as cold streams radiate Lyman-α photons. These cold streams are apparently responsible for feeding central galaxies.

A magnetohydrodynamic model of the interaction between the solar wind and the interstellar medium shows that our heliosphere has a round shape, not a tail-like shape as usually assumed. The model reproduces the observations from Cassini, New Horizons and the two Voyager probes.

HD 74423 is an unusual binary star system containing two λ Boötis pulsators. TESS photometry reveals that one of the pair is pulsating along its tidal axis—but only in one hemisphere. Such an odd arrangement provides an interesting laboratory in which to study stellar pulsations and tidal distortion.

Parsons et al. calculate masses and radii for both members of a double white dwarf system, where the less-massive member is exhibiting non-radial g-mode pulsations, making it a prime target for asteroseismic analyses.

Radio observations of black hole MAXI J1820+070’s 2018 outburst captured an isolated radio flare that the authors connect with the launch of bipolar relativistic ejecta. Following the oncoming ejecta for more than half a year reveals that black hole jet energetics have been systematically underestimated.

Observations of the Faraday rotation towards pulsars in the halo globular cluster 47 Tucanae have been used to constrain the magnetic field strength in the Galactic halo, finding that it is unexpectedly strong.

The European Southern Observatory trialled a distributed peer-review system—augmented by automated reviewer assignment—for its telescope time allocation process, finding that it worked as well as the standard process but resulted in a smaller burden on reviewers.

As the Tianwen-1 spacecraft is scheduled for launch in late July or early August, the mission chief scientist and his team provide an overview focusing on the scientific objectives and instrumentation of China’s first Mars mission.

The Emirates will shortly join the ranks of space-faring nations by sending an orbiter to Mars, aiming to make novel observations and inspire the country, write the mission leadership team.