Search Publications
The Large, Oxygen-Rich Halos of Star-Forming Galaxies Are a Major Reservoir of Galactic Metals
Sembach, K. R.; Davé, R.; Prochaska, J. X. +11 more
The circumgalactic medium (CGM) is fed by galaxy outflows and accretion of intergalactic gas, but its mass, heavy element enrichment, and relation to galaxy properties are poorly constrained by observations. In a survey of the outskirts of 42 galaxies with the Cosmic Origins Spectrograph onboard the Hubble Space Telescope, we detected ubiquitous, …
The Origins of Hot Plasma in the Solar Corona
Schrijver, C. J.; De Pontieu, B.; Tarbell, T. D. +6 more
The Sun's outer atmosphere, or corona, is heated to millions of degrees, considerably hotter than its surface or photosphere. Explanations for this enigma typically invoke the deposition in the corona of nonthermal energy generated by magnetoconvection. However, the coronal heating mechanism remains unknown. We used observations from the Solar Dyn…
Herschel Detects a Massive Dust Reservoir in Supernova 1987A
van Loon, J. Th.; Lundqvist, P.; Okumura, K. +20 more
We report far-infrared and submillimeter observations of supernova 1987A, the star whose explosion was observed on 23 February 1987 in the Large Magellanic Cloud, a galaxy located 160,000 light years away. The observations reveal the presence of a population of cold dust grains radiating with a temperature of about 17 to 23 kelvin at a rate of abo…
An Extremely Luminous Panchromatic Outburst from the Nucleus of a Distant Galaxy
Cenko, S. B.; Sánchez-Ramírez, R.; Cooper, M. C. +60 more
Variable x-ray and γ-ray emission is characteristic of the most extreme physical processes in the universe. We present multiwavelength observations of a unique γ-ray-selected transient detected by the Swift satellite, accompanied by bright emission across the electromagnetic spectrum, and whose properties are unlike any previously observed source.…
Discovery of Powerful Gamma-Ray Flares from the Crab Nebula
Bignami, G. F.; Costa, E.; Mereghetti, S. +65 more
The well-known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here, we report the detection of strong gamma-ray (…
Baryons at the Edge of the X-ray-Brightest Galaxy Cluster
Fabian, Andrew C.; Sanders, Jeremy S.; Allen, Steven W. +8 more
Studies of the diffuse x-ray-emitting gas in galaxy clusters have provided powerful constraints on cosmological parameters and insights into plasma astrophysics. However, measurements of the faint cluster outskirts have become possible only recently. Using data from the Suzaku x-ray telescope, we determined an accurate, spatially resolved census o…
Detection of the Water Reservoir in a Forming Planetary System
Cleeves, L. Ilsedore; Bergin, Edwin A.; van Dishoeck, Ewine F. +12 more
Icy bodies may have delivered the oceans to the early Earth, yet little is known about water in the ice-dominated regions of extrasolar planet-forming disks. The Heterodyne Instrument for the Far-Infrared on board the Herschel Space Observatory has detected emission lines from both spin isomers of cold water vapor from the disk around the young st…
Polarized Gamma-Ray Emission from the Galactic Black Hole Cygnus X-1
Rodriguez, J.; Wilms, J.; Laurent, P. +3 more
Because of their inherently high flux allowing the detection of clear signals, black hole x-ray binaries are interesting candidates for polarization studies, even if no polarization signals have been observed from them before. Such measurements would provide further detailed insight into these sources’ emission mechanisms. We measured the polariza…
Rapid and Extensive Surface Changes Near Titan’s Equator: Evidence of April Showers
Barnes, J. W.; Lorenz, R. D.; West, R. A. +11 more
Although there is evidence that liquids have flowed on the surface at Titan’s equator in the past, to date, liquids have only been confirmed on the surface at polar latitudes, and the vast expanses of dunes that dominate Titan’s equatorial regions require a predominantly arid climate. We report the detection by Cassini’s Imaging Science Subsystem …
The Hidden Mass and Large Spatial Extent of a Post-Starburst Galaxy Outflow
Bowen, David V.; Tripp, Todd M.; Jenkins, Edward B. +9 more
Outflowing winds of multiphase plasma have been proposed to regulate the buildup of galaxies, but key aspects of these outflows have not been probed with observations. By using ultraviolet absorption spectroscopy, we show that “warm-hot” plasma at 105.5 kelvin contains 10 to 150 times more mass than the cold gas in a post-starburst gala…