News & Comment

With a growing coverage of the night sky, the quantity and quality of transient event detections is booming. In this issue, our Focus looks particularly at observations of different types of supernovae and the need for a classification scheme that can systematically accommodate the diversity of stellar explosions and progenitors.

Machine learning and related methods will be crucial for automatically classifying transients as they happen in order to best allocate follow-up resources. Such techniques cannot be used off the shelf, but must be developed by the community as a whole.

Besides supernovae, few astrophysical processes can release close to 10⁵¹ erg of energy. A growing number of stellar outbursts are now recognized to have energy releases matching those of faint supernovae. These transients can be triggered by various mechanisms, and their discrimination is sometimes a tricky issue.

The Faint Intergalactic medium Redshifted Emission Balloon (FIREBall-2) is an ultraviolet multi-object spectrograph mission designed to observe the faint gas surrounding z ≈ 0.7 galaxies from the very top of the Earth’s stratosphere, explains Project Scientist Erika Hamden.

We all benefit when astronomy, and other sciences, are deconstructed and re-imagined in a different light to create activities accessible to all, independent of age, nationality, socioeconomic status, location, educational level, or mental or physical ability.

We publish in this issue our first Matters Arising, a new way for Nature Research journals to host a sound and peer-reviewed debate driven by the community on a stimulating (and maybe polarizing) topic presented in a published paper.

Renewed investment in lunar exploration (and beyond) will benefit basic research and applied science, but we need to tread carefully in order to prevent the exploitation of extraterrestrial resources.

The 4-metre Multi-Object Spectroscopic Telescope (4MOST) is a versatile optical survey instrument that will be installed on the VISTA telescope in 2022, offering medium- and high-resolution spectra and an innovative operations mode, explains Principal Investigator Roelof de Jong on behalf of the 4MOST Consortium.

Astrobiologists hope to detect signs of life on ocean worlds such as Europa. But the major challenge will actually come if such detections are successful — how to prove they are real and not artefacts of contamination or exotic chemistry?

Although a major objective in Mars exploration is the search for life, there are many scenarios that could lead to the recovery of lifeless samples. What could lifeless samples tell us about Mars and its habitability?