Search Publications
Powering prolonged hydrothermal activity inside Enceladus
Postberg, Frank; Sotin, Christophe; Čadek, Ondřej +4 more
Geophysical data from the Cassini spacecraft imply the presence of a global ocean underneath the ice shell of Enceladus1, only a few kilometres below the surface in the South Polar Terrain2-4. Chemical analyses indicate that the ocean is salty5 and is fed by ongoing hydrothermal activity6-8. In order to …
The pristine interior of comet 67P revealed by the combined Aswan outburst and cliff collapse
Jorda, L.; Lara, L. M.; Bertaux, J. -L. +61 more
Outbursts occur commonly on comets1 with different frequencies and scales2,3. Despite multiple observations suggesting various triggering processes4,5, the driving mechanism of such outbursts is still poorly understood. Landslides have been invoked6 to explain some outbursts on comet 103P/Hartley 2, alth…
Analogues of primeval galaxies two billion years after the Big Bang
Castellano, Marco; Fontana, Adriano; Giavalisco, Mauro +30 more
Deep observations are revealing a growing number of young galaxies in the first billion years of cosmic time1. Compared to typical galaxies at later times, they show more extreme emission-line properties2, higher star formation rates3, lower masses4, and smaller sizes5. However, their faintnes…
Protostellar and cometary detections of organohalogens
Bourke, Tyler L.; Rosina Team; Öberg, Karin I. +15 more
Organohalogens, a class of molecules that contain at least one halogen atom bonded to carbon, are abundant on the Earth where they are mainly produced through industrial and biological processes1. Consequently, they have been proposed as biomarkers in the search for life on exoplanets2. Simple halogen hydrides have been detec…
An elevation of 0.1 light-seconds for the optical jet base in an accreting Galactic black hole system
Harrison, F. A.; Stern, D.; Altamirano, D. +25 more
Relativistic plasma jets are observed in many systems that host accreting black holes. According to theory, coiled magnetic fields close to the black hole accelerate and collimate the plasma, leading to a jet being launched1-3. Isolating emission from this acceleration and collimation zone is key to measuring its size and understanding …
High-resolution observations of flare precursors in the low solar atmosphere
Xu, Yan; Cao, Wenda; Liu, Chang +9 more
Solar flares are generally believed to be powered by free magnetic energy stored in the corona1, but the build up of coronal energy alone may be insufficient to trigger the flare to occur2. The flare onset mechanism is a critical but poorly understood problem, insights into which could be gained from small-scale energy releas…
A likely decade-long sustained tidal disruption event
Ramirez-Ruiz, Enrico; Gwyn, Stephen D. J.; Komossa, S. +11 more
Multiwavelength flares from tidal disruption and accretion of stars can be used to find and study otherwise dormant massive black holes in galactic nuclei 1 . Previous well-monitored candidate flares were short-lived, with most emission confined to within ∼1 year 2-5 . Here we report the discovery of a well-observed super-lon…
A tidal disruption event in the nearby ultra-luminous infrared galaxy F01004-2237
Mullaney, J.; Rose, M.; Tadhunter, C. +2 more
Tidal disruption events (TDEs), in which stars are gravitationally disrupted as they pass close to the supermassive black holes in the centres of galaxies 1 , are potentially important probes of strong gravity and accretion physics. Most TDEs have been discovered in large-area monitoring surveys of many thousands of galaxies, and a rela…
Stars caught in the braking stage in young Magellanic Cloud clusters
D'Antona, Francesca; Milone, Antonino P.; Tailo, Marco +3 more
The colour-magnitude diagrams of many Magellanic Cloud clusters (with ages up to 2 billion years) display extended turnoff regions where the stars leave the main sequence, suggesting the presence of multiple stellar populations with ages that may differ even by hundreds of millions of years 1,2,3 . A strongly debated question is whether…
Millimetre-wave emission from an intermediate-mass black hole candidate in the Milky Way
Oka, Tomoharu; Tsujimoto, Shiho; Iwata, Yuhei +2 more
It is widely accepted that black holes with masses greater than a million solar masses (M⊙) lurk at the centres of massive galaxies. The origins of such `supermassive' black holes (SMBHs) remain unknown1, although those of stellar-mass black holes are well understood. One possible scenario is that intermediate-mass black hole…