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Rosetta begins its Comet Tale

Fulle, M.; Alexander, C.; Fulchignoni, M. +4 more

Philae's First Days on the Comet

Bibring, J. -P.; Mottola, S.; Alexander, C. +10 more

67P/Churyumov-Gerasimenko surface properties as derived from CIVA panoramic images

Le Mouélic, S.; Bibring, J. -P.; Gondet, B. +8 more

The structure and composition of cometary constituents, down to their microscopic scale, are critical witnesses of the processes and ingredients that drove the formation and evolution of planetary bodies toward their present diversity. On board Rosetta’s lander Philae, the Comet Infrared and Visible Analyser (CIVA) experiment took a series of imag…

The return of Philae

Clery, Daniel; Hand, Eric

Transient Water Vapor at Europa's South Pole

Nimmo, Francis; Saur, Joachim; Roth, Lorenz +4 more

In November and December 2012, the Hubble Space Telescope (HST) imaged Europa's ultraviolet emissions in the search for vapor plume activity. We report statistically significant coincident surpluses of hydrogen Lyman-α and oxygen OI 130.4-nanometer emissions above the southern hemisphere in December 2012. These emissions were persistently found in…

Thermal structure of an exoplanet atmosphere from phase-resolved emission spectroscopy

Madhusudhan, Nikku; Burrows, Adam; Fortney, Jonathan J. +13 more

Exoplanets that orbit close to their host stars are much more highly irradiated than their solar system counterparts. Understanding the thermal structures and appearances of these planets requires investigating how their atmospheres respond to such extreme stellar forcing. We present spectroscopic thermal emission measurements as a function of orb…

Prevalence of small-scale jets from the networks of the solar transition region and chromosphere

Weber, M.; Peter, H.; Golub, L. +24 more

As the interface between the Sun’s photosphere and corona, the chromosphere and transition region play a key role in the formation and acceleration of the solar wind. Observations from the Interface Region Imaging Spectrograph reveal the prevalence of intermittent small-scale jets with speeds of 80 to 250 kilometers per second from the narrow brig…

A fast and long-lived outflow from the supermassive black hole in NGC 5548

Kaastra, J. S.; Harrison, F. A.; Nandra, K. +31 more

Supermassive black holes in the nuclei of active galaxies expel large amounts of matter through powerful winds of ionized gas. The archetypal active galaxy NGC 5548 has been studied for decades, and high-resolution x-ray and ultraviolet (UV) observations have previously shown a persistent ionized outflow. An observing campaign in 2013 with six spa…

A local clue to the reionization of the universe

Heckman, Timothy M.; Leitherer, Claus; Borthakur, Sanchayeeta +1 more

Identifying the population of galaxies that was responsible for the reionization of the universe is a long-standing quest in astronomy. We present a possible local analog that has an escape fraction of ionizing flux of 21%. Our detection confirms the existence of gaps in the neutral gas enveloping the starburst region. The candidate contains a mas…

Hot explosions in the cool atmosphere of the Sun

Peter, H.; Golub, L.; Curdt, W. +20 more

The solar atmosphere was traditionally represented with a simple one-dimensional model. Over the past few decades, this paradigm shifted for the chromosphere and corona that constitute the outer atmosphere, which is now considered a dynamic structured envelope. Recent observations by the Interface Region Imaging Spectrograph (IRIS) reveal that it …