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Two super-earths orbiting the solar analog HD 41248 on the edge of a 7 : 5 mean motion resonance
(2013-07-01)
There are a growing number of multi-planet systems known to be orbiting their host stars with orbital periods that place them in mean motion resonances (MMRs). These systems are generally in first-order resonances and ...
Scratching the Surface : The Ethics of Mining Helium-3
(International Academy of Astronautics, 2013)
Terrestrial mining is ethically problematic by virtue of its directly destructive impact and by virtue of its contribution to both the depletion of fossil fuels and (through the use of the latter) to the raising of C02 ...
A planetary system with gas giants and super-Earths around the nearby M dwarf GJ676A : Optimizing data analysis techniques for the detection of multi-planetary systems
(2012-12-01)
Context. Several M dwarfs are targets of systematical monitoring in searches for Doppler signals caused by low-mass exoplanet companions. As a result, an emerging population of high-multiplicity planetary systems around ...
Astrometric and photometric initial mass functions from the UKIDSS Galactic Clusters Survey - II. The Alpha Persei open cluster
(2012-11-11)
We present the results of a deep (J = 19.1mag) infrared (ZYJHK) survey over the full α Per open cluster extracted from the Data Release 9 of the United Kingdom Infrared Telescope Infrared Deep Sky Survey Galactic Clusters ...
Astrometric and photometric initial mass functions from the UKIDSS Galactic Clusters Survey - III. Praesepe
(2012-11-11)
Over the past decades open clusters have been the subject of many studies. Such studies are crucial considering that the universality of the initial mass function is still a subject of current investigations. Praesepe is ...
Evidence for nine planets in the HD 10180 system
(2012-07-01)
Aims. We re-analyse the HARPS radial velocities of HD 10180 and calculate the probabilities of models with differing numbers of periodic signals in the data. We test the significance of the seven signals, corresponding to ...
Volcanic ash over Scandinavia originating from the Grímsvötn eruptions in May 2011
(2012-05-16)
A volcanic ash plume that originated from the eruptions of Iceland's Grímsvötn volcano in May 2011 was observed over the Nordic countries using a combination of satellite observations and ground-based measurements. The ...
Astrometric and photometric initial mass functions from the UKIDSS Galactic Clusters Survey - I. The Pleiades
(2012-05-01)
We present the results of a deep wide-field near-infrared survey of the entire Pleiades cluster recently released as part of the UKIRT Infrared Deep Sky Survey (UKIDSS) Galactic Clusters Survey (GCS) Data Release 9 (DR9). ...
Ice formation in ash-influenced clouds after the eruption of the Eyjafjallajkull volcano in April 2010
(2011-10-27)
The influence of volcanic ash on heterogeneous ice nucleation in tropospheric clouds is investigated on the basis of 90 observed cloud cases. The clouds were observed with polarization lidars at the two central-European ...
Ash and fine-mode particle mass profiles from EARLINET-AERONET observations over central Europe after the eruptions of the Eyjafjallajökull volcano in 2010
(2011-01-01)
A combined lidar-photometer method that permits the retrieval of vertical profiles of ash and non-ash (fine-mode) particle mass concentrations is presented. By using a polarization lidar, the contributions of non-ash and ...