Search Publications
Dust measurements in the coma of comet 67P/Churyumov-Gerasimenko inbound to the Sun
Accolla, Mario; Altobelli, Nicolas; Bertaux, Jean-Loup +78 more
Critical measurements for understanding accretion and the dust/gas ratio in the solar nebula, where planets were forming 4.5 billion years ago, are being obtained by the GIADA (Grain Impact Analyser and Dust Accumulator) experiment on the European Space Agency’s Rosetta spacecraft orbiting comet 67P/Churyumov-Gerasimenko. Between 3.6 and 3.4 astro…
67P/Churyumov-Gerasimenko, a Jupiter family comet with a high D/H ratio
Wurz, P.; Bochsler, P.; Altwegg, K. +29 more
The provenance of water and organic compounds on Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the deuterium-to-hydrogen (D/H) ratios in the reservoirs for comets and Earth’s oceans. Here, we report the direct i…
The organic-rich surface of comet 67P/Churyumov-Gerasimenko as seen by VIRTIS/Rosetta
Langevin, Y.; Bellucci, G.; Jaumann, R. +75 more
The VIRTIS (Visible, Infrared and Thermal Imaging Spectrometer) instrument on board the Rosetta spacecraft has provided evidence of carbon-bearing compounds on the nucleus of the comet 67P/Churyumov-Gerasimenko. The very low reflectance of the nucleus (normal albedo of 0.060 ± 0.003 at 0.55 micrometers), the spectral slopes in visible and infrared…
Organic compounds on comet 67P/Churyumov-Gerasimenko revealed by COSAC mass spectrometry
Krüger, Harald; McKenna-Lawlor, Susan; Gautier, Thomas +18 more
Comets harbor the most pristine material in our solar system in the form of ice, dust, silicates, and refractory organic material with some interstellar heritage. The evolved gas analyzer Cometary Sampling and Composition (COSAC) experiment aboard Rosetta’s Philae lander was designed for in situ analysis of organic molecules on comet 67P/Churyumov…
Black hole feedback in the luminous quasar PDS 456
Harrison, F. A.; Stern, D.; Behar, E. +17 more
The evolution of galaxies is connected to the growth of supermassive black holes in their centers. During the quasar phase, a huge luminosity is released as matter falls onto the black hole, and radiation-driven winds can transfer most of this energy back to the host galaxy. Over five different epochs, we detected the signatures of a nearly spheri…
Molecular nitrogen in comet 67P/Churyumov-Gerasimenko indicates a low formation temperature
Wurz, P.; Bochsler, P.; Altwegg, K. +29 more
Molecular nitrogen (N2) is thought to have been the most abundant form of nitrogen in the protosolar nebula. It is the main N-bearing molecule in the atmospheres of Pluto and Triton and probably the main nitrogen reservoir from which the giant planets formed. Yet in comets, often considered the most primitive bodies in the solar system,…
Particle acceleration by a solar flare termination shock
Krucker, Säm; Chen, Bin; Gary, Dale E. +3 more
Solar flares—the most powerful explosions in the solar system—are also efficient particle accelerators, capable of energizing a large number of charged particles to relativistic speeds. A termination shock is often invoked in the standard model of solar flares as a possible driver for particle acceleration, yet its existence and role have remained…
The landing(s) of Philae and inferences about comet surface mechanical properties
Auster, Hans-Ulrich; Heinisch, Philip; Güttler, Carsten +30 more
The Philae lander, part of the Rosetta mission to investigate comet 67P/Churyumov-Gerasimenko, was delivered to the cometary surface in November 2014. Here we report the precise circumstances of the multiple landings of Philae, including the bouncing trajectory and rebound parameters, based on engineering data in conjunction with operational instr…
The exceptionally powerful TeV γ-ray emitters in the Large Magellanic Cloud
Klochkov, D.; Santangelo, A.; Quirrenbach, A. +226 more
The Large Magellanic Cloud, a satellite galaxy of the Milky Way, has been observed with the High Energy Stereoscopic System (H.E.S.S.) above an energy of 100 billion electron volts for a deep exposure of 210 hours. Three sources of different types were detected: the pulsar wind nebula of the most energetic pulsar known, N 157B; the radio-loud supe…
Properties of the 67P/Churyumov-Gerasimenko interior revealed by CONSERT radar
Elachi, Charles; Sierks, Holger; Nielsen, Erling +23 more
The Philae lander provides a unique opportunity to investigate the internal structure of a comet nucleus, providing information about its formation and evolution in the early solar system. We present Comet Nucleus Sounding Experiment by Radiowave Transmission (CONSERT) measurements of the interior of Comet 67P/Churyumov-Gerasimenko. From the propa…