ROSAT Ian R. Stevens* and David K. Strickland*
... We note that the detection of a broad He II l4686 feature can be difficult even with high signal-to-noise ratio (S/N) data. This does mean that our sample of WR galaxies will tend to be rather heterogenous. Future studies will have to focus on broader samples of starburst galaxies and starburst regi ...
... We note that the detection of a broad He II l4686 feature can be difficult even with high signal-to-noise ratio (S/N) data. This does mean that our sample of WR galaxies will tend to be rather heterogenous. Future studies will have to focus on broader samples of starburst galaxies and starburst regi ...
Hubble 2006: Science Year in Review
... The servicing mission in 1999 enhanced many of Hubble’s subsystems, including the central computer, a new solid-state data-recording system to replace the aging magnetic tape drives, and the gyroscopes needed for pointing control. A month prior to launch, a gyroscope failure had forced Hubble into ...
... The servicing mission in 1999 enhanced many of Hubble’s subsystems, including the central computer, a new solid-state data-recording system to replace the aging magnetic tape drives, and the gyroscopes needed for pointing control. A month prior to launch, a gyroscope failure had forced Hubble into ...
IOTA Observer`s Manual
... discoverer of Uranus, William Herschel, as he noticed faint stars dim as the planet passed close by. Occultation observations are fun to observe. There is perhaps nothing more exciting than watching a star vanish and return from behind a lunar mountain, or to see the star disappear for several secon ...
... discoverer of Uranus, William Herschel, as he noticed faint stars dim as the planet passed close by. Occultation observations are fun to observe. There is perhaps nothing more exciting than watching a star vanish and return from behind a lunar mountain, or to see the star disappear for several secon ...
La Sapienza – 2015
... • HARPS-South and HARPS-North (High Accuracy Radial velocity Planet Searcher) are the most accurate spectrographs ever built. ...
... • HARPS-South and HARPS-North (High Accuracy Radial velocity Planet Searcher) are the most accurate spectrographs ever built. ...
On the characterisation of the Galactic warp in the Gaia era
... from them. You both are the best teachers any student can ask for. Thank you Francesca for all of your support and patience, aspiring guidance and immense knowledge. You always made time to help and advise me. I have been a pleasure for me to work with you. Also, I really appreciate you being so sen ...
... from them. You both are the best teachers any student can ask for. Thank you Francesca for all of your support and patience, aspiring guidance and immense knowledge. You always made time to help and advise me. I have been a pleasure for me to work with you. Also, I really appreciate you being so sen ...
THE 2MASS WIDE-FIELD T DWARF SEARCH. II. DISCOVERY OF
... and Ks photometric bands sampled by 2MASS. The optical/near-infrared colors of T dwarfs are also extremely red (RJ e 9; Golimowski et al. 1998); hence, photographic plate surveys, which also cover the whole sky, cannot detect T dwarfs much farther than a few parsecs from the Sun (Scholz et al. 2003 ...
... and Ks photometric bands sampled by 2MASS. The optical/near-infrared colors of T dwarfs are also extremely red (RJ e 9; Golimowski et al. 1998); hence, photographic plate surveys, which also cover the whole sky, cannot detect T dwarfs much farther than a few parsecs from the Sun (Scholz et al. 2003 ...
Document
... class of variables because it was: – Among one of the brightest members of the new class – The best studied of the sample – Showed a good range of the absorption/emission features used to characterize the set of stars ...
... class of variables because it was: – Among one of the brightest members of the new class – The best studied of the sample – Showed a good range of the absorption/emission features used to characterize the set of stars ...
W.M. Keck Observatory Annual Report 2009
... the planets with the lowest possible mass. The Keck I telescope has been the most prolific scientific instrument in the world for finding exoplanets, the majority of them being gas giants, like Jupiter. Even with that great success, we are still left with a glaring holy grail—detecting the first ext ...
... the planets with the lowest possible mass. The Keck I telescope has been the most prolific scientific instrument in the world for finding exoplanets, the majority of them being gas giants, like Jupiter. Even with that great success, we are still left with a glaring holy grail—detecting the first ext ...
environmental effects on galaxy evolution in nearby clusters
... The observational evidences presented in this work suggest that: (I) Giant ellipticals are an old, homogeneous population showing no or little evolution at least in the past 8 Gyr; unlike dwarf ellipticals which still contain young stellar populations. (II) The importance of different environmental ...
... The observational evidences presented in this work suggest that: (I) Giant ellipticals are an old, homogeneous population showing no or little evolution at least in the past 8 Gyr; unlike dwarf ellipticals which still contain young stellar populations. (II) The importance of different environmental ...
Elliptical Galaxies
... true distribution. He estimated that on average ellipticals have a short axis about 65% of the length of the long axis with a dispersion of about 15%. This picture remained current until the late 1970s but has been dramatically revised since then. In recent years attempts to produce a physical class ...
... true distribution. He estimated that on average ellipticals have a short axis about 65% of the length of the long axis with a dispersion of about 15%. This picture remained current until the late 1970s but has been dramatically revised since then. In recent years attempts to produce a physical class ...
X-Ray Spectroscopy of Stars
... as X-ray sources, with only a few exceptions, most notably A-type stars and the coolest giants of spectral type M. But even for those two classes, important exceptions exist. X-rays have been identified from the most massive and hottest stars, i.e., O-type and Wolf-Rayet stars, for which shocks form ...
... as X-ray sources, with only a few exceptions, most notably A-type stars and the coolest giants of spectral type M. But even for those two classes, important exceptions exist. X-rays have been identified from the most massive and hottest stars, i.e., O-type and Wolf-Rayet stars, for which shocks form ...
General NG Celestial Questions
... A. rapid changes in GHA and declination introduce errors into the calculations B. lack of a well defined limb during certain phases and positions in the sky C. approximations used in the solution caused by the variable horizontal parallax D. augmentation effect caused by the relatively short distanc ...
... A. rapid changes in GHA and declination introduce errors into the calculations B. lack of a well defined limb during certain phases and positions in the sky C. approximations used in the solution caused by the variable horizontal parallax D. augmentation effect caused by the relatively short distanc ...
Communications in Asteroseismology
... Michel (as pronounced in German with a guttural “ch”) and still is Michel to his university administration and to the Austrian Academy of Sciences; he is Mike (from his South African and American nick-name) to his many students past and present, and to most of the international astronomical communit ...
... Michel (as pronounced in German with a guttural “ch”) and still is Michel to his university administration and to the Austrian Academy of Sciences; he is Mike (from his South African and American nick-name) to his many students past and present, and to most of the international astronomical communit ...
Here - NASA/IPAC Extragalactic Database
... at which one is working). The effective temperatures T? of the ionizing stars lie in the range 35 000 – 50 000 K. The nebular geometries result from the structure of the parent molecular cloud. Stellar winds, at evolved stages, may produce ring-like structures, but the morphology of H ii regions is ...
... at which one is working). The effective temperatures T? of the ionizing stars lie in the range 35 000 – 50 000 K. The nebular geometries result from the structure of the parent molecular cloud. Stellar winds, at evolved stages, may produce ring-like structures, but the morphology of H ii regions is ...
1 Globular Cluster Systems - McMaster Physics and Astronomy
... used by Shapley to estimate the centroid of the system and thus { again for the rst time { to determine the distance from the Sun to the Galactic center. The second graph shows us exactly the same plot with the most modern measurements. The data have improved dramatically over the intervening 80 ye ...
... used by Shapley to estimate the centroid of the system and thus { again for the rst time { to determine the distance from the Sun to the Galactic center. The second graph shows us exactly the same plot with the most modern measurements. The data have improved dramatically over the intervening 80 ye ...
The Lupus clouds - European Southern Observatory
... lies at a similar distance from the Sun and has a similar mass of molecular gas but more vigorous star forming activity (see review by Wilking et al. in this volume) occupies a position with respect to Lupus that is roughly symmetric with respect to the center of the Upper Scorpius OB group. The sce ...
... lies at a similar distance from the Sun and has a similar mass of molecular gas but more vigorous star forming activity (see review by Wilking et al. in this volume) occupies a position with respect to Lupus that is roughly symmetric with respect to the center of the Upper Scorpius OB group. The sce ...
The Astrology of Space - Matrix Astrology Software
... All rights reserved. No part of the publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of the publisher. Graphics designed by Michael Erlewine Some graph ...
... All rights reserved. No part of the publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of the publisher. Graphics designed by Michael Erlewine Some graph ...
WFC3 Science White Paper - Space Telescope Science Institute
... such as the astrophysical plasma diagnostic emission line [O II] 3727 Å. However, neither STIS nor ACS offer good sensitivity over wide fields in the 2000-4000 Å spectral region. For moderate and high-redshift objects (z 0.4), the restframe far-89 Å) is redshifted into the 2000-4000 ...
... such as the astrophysical plasma diagnostic emission line [O II] 3727 Å. However, neither STIS nor ACS offer good sensitivity over wide fields in the 2000-4000 Å spectral region. For moderate and high-redshift objects (z 0.4), the restframe far-89 Å) is redshifted into the 2000-4000 ...
Ursa Minor
Ursa Minor (Latin: ""Smaller She-Bear"", contrasting with Ursa Major), also known as the Little Bear, is a constellation in the northern sky. Like the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, hence the name Little Dipper. It was one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and remains one of the 88 modern constellations. Ursa Minor has traditionally been important for navigation, particularly by mariners, due to Polaris being the North Star.Polaris, the brightest star in the constellation, is a yellow-white supergiant and the brightest Cepheid variable star in the night sky, ranging from apparent magnitude 1.97 to 2.00. Beta Ursae Minoris, also known as Kochab, is an aging star that has swollen and cooled to become an orange giant with an apparent magnitude of 2.08, only slightly fainter than Polaris. Kochab and magnitude 3 Gamma Ursae Minoris have been called the ""guardians of the pole star"". Planets have been detected orbiting four of the stars, including Kochab. The constellation also contains an isolated neutron star—Calvera—and H1504+65, the hottest white dwarf yet discovered with a surface temperature of 200,000 K.