Search Publications
The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
Brown, Anthony G. A.; Helmi, Amina; Babusiaux, Carine +3 more
The assembly of our Galaxy can be reconstructed using the motions and chemistry of individual stars1,2. Chemo-dynamical studies of the stellar halo near the Sun have indicated the presence of multiple components3, such as streams4 and clumps5, as well as correlations between the stars' chemical abundance…
A dynamically young and perturbed Milky Way disk
Figueras, F.; Evans, D. W.; Helmi, A. +10 more
The evolution of the Milky Way disk, which contains most of the stars in the Galaxy, is affected by several phenomena. For example, the bar and the spiral arms of the Milky Way induce radial migration of stars1 and can trap or scatter stars close to orbital resonances2. External perturbations from satellite galaxies can also …
Non-gravitational acceleration in the trajectory of 1I/2017 U1 ('Oumuamua)
Chambers, Kenneth C.; Wainscoat, Richard J.; Weaver, Harold A. +14 more
'Oumuamua (1I/2017 U1) is the first known object of interstellar origin to have entered the Solar System on an unbound and hyperbolic trajectory with respect to the Sun. Various physical observations collected during its visit to the Solar System showed that it has an unusually elongated shape and a tumbling rotation state and that the physical pr…
A candidate super-Earth planet orbiting near the snow line of Barnard's star
Rebolo, R.; Amado, P. J.; Caballero, J. A. +60 more
Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3…
An evolving jet from a strongly magnetized accreting X-ray pulsar
Degenaar, N.; Wijnands, R.; Miller-Jones, J. C. A. +4 more
Relativistic jets are observed throughout the Universe and strongly affect their surrounding environments on a range of physical scales, from Galactic binary systems1 to galaxies and clusters of galaxies2. All types of accreting black hole and neutron star have been observed to launch jets3, with the exception of n…
Evidence of ancient Milky Way merger
Venn, Kim
An analysis of data from the Gaia space observatory suggests that stars in the inner halo of the Milky Way originated in another galaxy. This galaxy is thought to have collided with the Milky Way about ten billion years ago.
A key piece in the exoplanet puzzle
Díaz, Rodrigo F.
The detection of a low-mass exoplanet on a relatively wide orbit has implications for models of planetary formation and evolution, and could open the door to a new era of exoplanet characterization.
Billion-star map of Milky Way set to transform astronomy
Castelvecchi, Davide
European Gaia spacecraft's first major data dump — the most detailed 3D chart yet of our Galaxy — will keep researchers busy for decades.
A fresh approach to stellar benchmarking
Beaton, Rachael
An avalanche of data is about to revolutionize astronomy, but the options for validating those data have been limited. High-precision measurements from the Hubble Space Telescope enable a much-needed alternative option.