Search Publications
Major Galaxy Mergers and the Growth of Supermassive Black Holes in Quasars
Schawinski, Kevin; Natarajan, Priyamvada; Urry, C. Megan +3 more
Despite observed strong correlations between central supermassive black holes (SMBHs) and star formation in galactic nuclei, uncertainties exist in our understanding of their coupling. We present observations of the ratio of heavily obscured to unobscured quasars as a function of cosmic epoch up to z ≅ 3 and show that a simple physical model descr…
E-Type Asteroid (2867) Steins as Imaged by OSIRIS on Board Rosetta
Jorda, L.; Bertaux, J. -L.; Lamy, P. +44 more
The European Space Agency’s Rosetta mission encountered the main-belt asteroid (2867) Steins while on its way to rendezvous with comet 67P/Churyumov-Gerasimenko. Images taken with the OSIRIS (optical, spectroscopic, and infrared remote imaging system) cameras on board Rosetta show that Steins is an oblate body with an effective spherica…
Direct Imaging of Bridged Twin Protoplanetary Disks in a Young Multiple Star
Pyo, Tae-Soo; Tamura, Motohide; Hayashi, Masahiko +10 more
Studies of the structure and evolution of protoplanetary disks are important for understanding star and planet formation. Here we present the direct image of an interacting binary protoplanetary system. Both circumprimary and circumsecondary disks are resolved in the near-infrared. There is a bridge of infrared emission connecting the two disks an…
Iapetus: Unique Surface Properties and a Global Color Dichotomy from Cassini Imaging
West, Robert A.; Porco, Carolyn C.; Burns, Joseph A. +8 more
Since 2004, Saturn’s moon Iapetus has been observed repeatedly with the Imaging Science Subsystem of the Cassini spacecraft. The images show numerous impact craters down to the resolution limit of ~10 meters per pixel. Small, bright craters within the dark hemisphere indicate a dark blanket thickness on the order of meters or less. Dark, equator-f…
Observing Supernova 1987A with the Refurbished Hubble Space Telescope
Smith, Nathan; Pun, Chun S. J.; France, Kevin +18 more
Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 with the use of the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph fa…
Saturn: Atmosphere, Ionosphere, and Magnetosphere
Ingersoll, Andrew P.; Gombosi, Tamas I.
The Cassini spacecraft has been in orbit around Saturn since 30 June 2004, yielding a wealth of data about the Saturn system. This review focuses on the atmosphere and magnetosphere and briefly outlines the state of our knowledge after the Cassini prime mission. The mission has addressed a host of fundamental questions: What processes control the …
Character and Spatial Distribution of OH/H2O on the Surface of the Moon Seen by M3 on Chandrayaan-1
Clark, R. N.; Head, J. W.; Kumar, S. +26 more
The search for water on the surface of the anhydrous Moon had remained an unfulfilled quest for 40 years. However, the Moon Mineralogy Mapper (M3) on Chandrayaan-1 has recently detected absorption features near 2.8 to 3.0 micrometers on the surface of the Moon. For silicate bodies, such features are typically attributed to hydroxyl- and…
Imaging the Interaction of the Heliosphere with the Interstellar Medium from Saturn with Cassini
Hsieh, K. C.; Krimigis, S. M.; Mitchell, D. G. +2 more
We report an all-sky image of energetic neutral atoms (ENAs) >6 kilo-electron volts produced by energetic protons occupying the region (heliosheath) between the boundary of the extended solar atmosphere and the local interstellar medium (LISM). The map obtained by the Ion and Neutral Camera (INCA) onboard Cassini reveals a broad belt of energet…
The Disappearance of the Progenitors of Supernovae 1993J and 2003gd
Smartt, Stephen J.; Maund, Justyn R.
Using images from the Hubble Space Telescope and the Gemini Telescope, we confirmed the disappearance of the progenitors of two type II supernovae (SNe) and evaluated the presence of other stars associated with them. We found that the progenitor of SN 2003gd, an M-supergiant star, is no longer observed at the SN location and determined its intrins…
An Ultramassive, Fast-Spinning White Dwarf in a Peculiar Binary System
Tiengo, A.; Mereghetti, S.; Stella, L. +3 more
White dwarfs typically have masses in a narrow range centered at about 0.6 solar mass (M⊙). Only a few ultramassive white dwarfs (mass > 1.2 M⊙) are known. Those in binary systems are of particular interest, because a small amount of accreted mass could drive them above the Chandrasekhar limit, beyond which they become gra…