Vera Rubin (1928–2016)
Nature 542, 7639 (2017). doi:10.1038/542032a
Author: Neta A. Bahcall
Observational astronomer who confirmed the existence of dark matter.
How to reach a planet 40 trillion kilometres away
Nature 542, 7639 (2017). http://www.nature.com/doifinder/10.1038/542020a
Author: Gabriel Popkin
A wild plan is taking shape to visit the nearest planet outside our Solar System. Here’s how we could get to Proxima b.
Astronomers explore uses for AI-generated images
Nature 542, 7639 (2017). http://www.nature.com/doifinder/10.1038/542016a
Author: Davide Castelvecchi
Neural networks produce pictures to train image-recognition programs and scientific software.
Planetary science: Pluto's dark equator explained
Nature 542, 7639 (2017). doi:10.1038/542008a
The cosmic impact that formed Pluto's moon Charon several billion years ago may also have created the dark regions seen at Pluto's equator (pictured).Scientists led by Yasuhito Sekine at the University of Tokyo ran laboratory experiments to see what might happen if a comet
Ruthenium isotopic evidence for an inner Solar System origin of the late veneer
Nature 541, 7638 (2017). doi:10.1038/nature21045
Authors: Mario Fischer-Gödde & Thorsten Kleine
The excess of highly siderophile elements in the Earth’s mantle is thought to reflect the addition of primitive meteoritic material after core formation ceased. This ‘late veneer’ either comprises material remaining in the terrestrial planet region after the main stages of the Earth’s accretion, or derives from more distant asteroidal or cometary sources. Distinguishing between these disparate origins is important because a late veneer consisting of carbonaceous chondrite-like asteroids or comets could be the principal source of the Earth’s volatiles and water. Until now, however, a ‘genetic’ link between the late veneer and such volatile-rich materials has not been established or ruled out. Such genetic links can be determined using ruthenium (Ru) isotopes, because the Ru in the Earth’s mantle predominantly derives from the late veneer, and because meteorites exhibit Ru isotope variations arising from the heterogeneous distribution of stellar-derived dust. Although Ru isotopic data and the correlation of Ru and molybdenum (Mo) isotope anomalies in meteorites were previously used to argue that the late veneer derives from the same type of inner Solar System material as do Earth’s main building blocks, the Ru isotopic composition of carbonaceous chondrites has not been determined sufficiently well to rule them out as a source of the late veneer. Here we show that all chondrites, including carbonaceous chondrites, have Ru isotopic compositions distinct from that of the Earth’s mantle. The Ru isotope anomalies increase from enstatite to ordinary to carbonaceous chondrites, demonstrating that material formed at greater heliocentric distance contains larger Ru isotope anomalies. Therefore, these data refute an outer Solar System origin for the late veneer and imply that the late veneer was not the primary source of volatiles and water on the Earth.
Astrophysics: Odd dwarf star is a pulsar
Nature 541, 7638 (2017). doi:10.1038/541439e
Strongly magnetized stars that shoot beams of radiation from their poles, called pulsars, have previously always been identified as dense neutron stars. But researchers now report the discovery of a pulsar that is a white dwarf — the spent remnant of a star like the
Axions: Detecting particles of dark matter
Nature 541, 7638 (2017). doi:10.1038/541464d
Authors: Jihn E. Kim, Pierre Sikivie & Steven Weinberg
Your article on the Axion Dark Matter eXperiment (ADMX) suggests that the lattice quantum chromodynamics (QCD) calculation by S. Borsanyi et al. (Nature539, 69–71;10.1038\nature201152016) might be bad news for the ADMX because it could place