Search Publications
Reconstructing galaxy histories from globular clusters
Jordán, Andrés; Marzke, Ronald O.; Côté, Patrick +1 more
Nearly a century after the true nature of galaxies as distant `island universes' was established, their origin and evolution remain great unsolved problems of modern astrophysics. One of the most promising ways to investigate galaxy formation is to study the ubiquitous globular star clusters that surround most galaxies. Globular clusters are compa…
An interplanetary shock traced by planetary auroral storms from the Sun to Saturn
Vourlidas, Angelos; Hansen, Kenneth C.; Prangé, Renée +4 more
A relationship between solar activity and aurorae on Earth was postulated long before space probes directly detected plasma propagating outwards from the Sun. Violent solar eruption events trigger interplanetary shocks that compress Earth's magnetosphere, leading to increased energetic particle precipitation into the ionosphere and subsequent auro…
The interstellar N2 abundance towards HD 124314 from far-ultraviolet observations
Andersson, B. -G.; McCandliss, Stephan R.; Knauth, David C. +1 more
The abundance of interstellar molecular nitrogen (N2) is of considerable importance: models of steady-state gas-phase interstellar chemistry, together with millimetre-wavelength observations of interstellar N2H+ in dense molecular clouds predict that N2 should be the most abundant nitrogen-bearing molecu…
A distance of 133-137 parsecs to the Pleiades star cluster
Kulkarni, S. R.; Shao, M.; Pan, Xiaopei
Nearby `open' clusters of stars (those that are not gravitationally bound) have played a crucial role in the development of stellar astronomy because, as a consequence of the stars having a common age, they provide excellent natural laboratories to test theoretical stellar models. Clusters also play a fundamental part in determining distance scale…
Compact sources as the origin of the soft γ-ray emission of the Milky Way
Strong, A. W.; Walter, R.; Ubertini, P. +16 more
The Milky Way is known to be an abundant source of γ-ray photons, now determined to be mainly diffuse in nature and resulting from interstellar processes. In the soft γ-ray domain, point sources are expected to dominate, but the lack of sensitive high-resolution observations did not allow for a clear estimate of the contribution from such sources.…