Search Publications
Detection of nanoflare-heated plasma in the solar corona by the FOXSI-2 sounding rocket
Krucker, Säm; Narukage, Noriyuki; Glesener, Lindsay +4 more
The processes that heat the solar and stellar coronae to several million kelvins, compared with the much cooler photosphere (5,800 K for the Sun), are still not well known1. One proposed mechanism is heating via a large number of small, unresolved, impulsive heating events called nanoflares2. Each event would heat and cool qu…
The independent pulsations of Jupiter's northern and southern X-ray auroras
Coates, A. J.; Jackman, C. M.; Jones, G. H. +14 more
Auroral hot spots are observed across the Universe at different scales1 and mark the coupling between a surrounding plasma environment and an atmosphere. Within our own Solar System, Jupiter possesses the only resolvable example of this large-scale energy transfer. Jupiter's northern X-ray aurora is concentrated into a hot spot, which i…
The large-scale nebular pattern of a superwind binary in an eccentric orbit
Morris, Mark R.; Liu, Sheng-Yuan; Taam, Ronald E. +5 more
Preplanetary nebulae and planetary nebulae are evolved, mass-losing stellar objects that show a wide variety of morphologies. Many of these nebulae consist of outer structures that are nearly spherical (spiral/shell/arc/halo) and inner structures that are highly asymmetric (bipolar/multipolar) 1,2 . The coexistence of such geometrically…
Cluster richness-mass calibration with cosmic microwave background lensing
Geach, James E.; Peacock, John A.
Identifying galaxy clusters through overdensities of galaxies in photometric surveys is the oldest1,2 and arguably the most economical and mass-sensitive detection method3,4, compared with X-ray5-7 and Sunyaev-Zel'dovich effect8 surveys that detect the hot intracluster medium. However, a perennial proble…
Disruption of Saturn's quasi-periodic equatorial oscillation by the great northern storm
Fletcher, Leigh N.; Irwin, Patrick G. J.; Flasar, F. Michael +7 more
The equatorial middle atmospheres of the Earth1, Jupiter2 and Saturn3,4 all exhibit a remarkably similar phenomenon—a vertical, cyclic pattern of alternating temperatures and zonal (east-west) wind regimes that propagate slowly downwards with a well-defined multi-year period. Earth's quasi-biennial oscillation (QBO…
Polarization due to rotational distortion in the bright star Regulus
Bailey, Jeremy; Cotton, Daniel V.; Howarth, Ian D. +4 more
Polarization in stars was first predicted by Chandrasekhar1, who calculated a substantial linear polarization at the stellar limb for a pure electron-scattering atmosphere. This polarization will average to zero when integrated over a spherical star but could be detected if the symmetry was broken, for example, by the eclipse of a binar…
Thermally anomalous features in the subsurface of Enceladus's south polar terrain
Sotin, C.; Lorenz, R. D.; West, R. D. +15 more
Saturn's moon Enceladus is an active world. In 2005, the Cassini spacecraft witnessed for the first time water-rich jets venting from four anomalously warm fractures (called sulci) near its south pole1,2. Since then, several observations have provided evidence that the source of the material ejected from Enceladus is a large underground…
Ten billion years of brightest cluster galaxy alignments
West, Michael J.; Phillipps, Steven; Bremer, Malcolm N. +1 more
A galaxy's orientation is one of its most basic observable properties. Astronomers once assumed that galaxies are randomly oriented in space; however, it is now clear that some have preferred orientations with respect to their surroundings. Chief among these are giant elliptical galaxies found in the centres of rich galaxy clusters. Numerous studi…
Spectroscopic confirmation of an ultra-faint galaxy at the epoch of reionization
Pentericci, Laura; Schmidt, Kasper B.; Treu, Tommaso +11 more
Within one billion years of the Big Bang, intergalactic hydrogen was ionized by sources emitting ultraviolet and higher energy photons. This was the final phenomenon to globally affect all the baryons (visible matter) in the Universe. It is referred to as cosmic reionization and is an integral component of cosmology. It is broadly expected that in…
Stationary waves and slowly moving features in the night upper clouds of Venus
Hueso, R.; Sánchez-Lavega, A.; Kouyama, T. +9 more
At the cloud top level of Venus (65-70 km altitude) the atmosphere rotates 60 times faster than the underlying surface—a phenomenon known as superrotation1,2. Whereas on Venus's dayside the cloud top motions are well determined3,4,5,6 and Venus general circulation models predict the mean zonal flow at the upper clouds to be s…