Pinpointing the Milky Way
... the focal plane assembly comprises a total of nearly 1000 million pixels (a ‘gigapixel’), compared to the few million of a typical digital camera. As Gaia slowly rotates, the image of a celestial object crosses the focal plane. The path it takes is recorded as astrometric data. Red and blue photomet ...
... the focal plane assembly comprises a total of nearly 1000 million pixels (a ‘gigapixel’), compared to the few million of a typical digital camera. As Gaia slowly rotates, the image of a celestial object crosses the focal plane. The path it takes is recorded as astrometric data. Red and blue photomet ...
Altas Farnese
... the globe shows the head only as being near the Arctic Circle and the raven and cup as only tangent to the equator. Hipparchus was perhaps the greatest astronomer of Antiquity, his outstanding discovery being the precession of the equinoxes. He is said to have compiled a large star catalogue with at ...
... the globe shows the head only as being near the Arctic Circle and the raven and cup as only tangent to the equator. Hipparchus was perhaps the greatest astronomer of Antiquity, his outstanding discovery being the precession of the equinoxes. He is said to have compiled a large star catalogue with at ...
Behaviour of elements from lithium to europium in stars with and
... that the iron abundance log A(Fe) obtained from Fe I lines was not correlated with the equivalent width, EW. The adopted metallicity value [Fe/H] was the iron abundance obtained from the Fe I lines under the local thermodynamic equilibrium (LTE) approximation. We note that the non-LTE corrections fo ...
... that the iron abundance log A(Fe) obtained from Fe I lines was not correlated with the equivalent width, EW. The adopted metallicity value [Fe/H] was the iron abundance obtained from the Fe I lines under the local thermodynamic equilibrium (LTE) approximation. We note that the non-LTE corrections fo ...
Abstracts - Physics of Evolved Stars 2015
... During the past decade, an increasing number of observations have shown that, at least at some points, the mass-loss rate of red supergiants (RSG) could be significantly higher than the standard one, usually used in stellar evolution code. In this talk, I will show how an increased mass-loss rate du ...
... During the past decade, an increasing number of observations have shown that, at least at some points, the mass-loss rate of red supergiants (RSG) could be significantly higher than the standard one, usually used in stellar evolution code. In this talk, I will show how an increased mass-loss rate du ...
1998 - Universitäts-Sternwarte München
... like the bright F5 star Procyon and the Moon, were repeatedly monitored for an intercomparison of different observing runs as well as different spectrograph settings. The results are encouraging in that redundant observations provide stellar atmospheric parameters with fairly small intrinsic scatter ...
... like the bright F5 star Procyon and the Moon, were repeatedly monitored for an intercomparison of different observing runs as well as different spectrograph settings. The results are encouraging in that redundant observations provide stellar atmospheric parameters with fairly small intrinsic scatter ...
Conference Abstract Booklet here.
... and extragalactic fields visited multiple times by the Hubble Space Telescope with the same instrument/filter combination. While some of these fields were searched for specific types of variables before (most notably, the extragalactic Cepheids), we attempt a systematic study of the population of va ...
... and extragalactic fields visited multiple times by the Hubble Space Telescope with the same instrument/filter combination. While some of these fields were searched for specific types of variables before (most notably, the extragalactic Cepheids), we attempt a systematic study of the population of va ...
the chandra deep field–north survey. xvii. evolution of
... unresolved X-ray sources over the entire CDF-N field, about 370 of which were previously reported in the 1 Ms CDF-N sample by Brandt et al. (2001). The field was accurately aligned to the FK5 reference frame via radio source counterparts. The median uncertainty of individual source positions is ’0B3 ...
... unresolved X-ray sources over the entire CDF-N field, about 370 of which were previously reported in the 1 Ms CDF-N sample by Brandt et al. (2001). The field was accurately aligned to the FK5 reference frame via radio source counterparts. The median uncertainty of individual source positions is ’0B3 ...
Magnetic cycles of Sun-like stars with different levels of coronal and
... (1995), observed in the Mount Wilson HK-project (filled circles). The solid line represents the Zero Age Main Sequence (ZAMS) on the Hertzsprung-Russell diagram. Stars, which are close to the ZAMS in Figure 1, have the lowest age among all other stars: log(Age/yr) is about 8 - 8.5. The older the sta ...
... (1995), observed in the Mount Wilson HK-project (filled circles). The solid line represents the Zero Age Main Sequence (ZAMS) on the Hertzsprung-Russell diagram. Stars, which are close to the ZAMS in Figure 1, have the lowest age among all other stars: log(Age/yr) is about 8 - 8.5. The older the sta ...
Comparing stars - The Open University
... red giants plus the stars to their left that lie between the main sequence and the supergiants. This class is the giants and is broader than that of red giants alone. You can see from Figure 5 that white dwarfs are, as their name implies, hot and small, only about the size of the Earth (Question 2). ...
... red giants plus the stars to their left that lie between the main sequence and the supergiants. This class is the giants and is broader than that of red giants alone. You can see from Figure 5 that white dwarfs are, as their name implies, hot and small, only about the size of the Earth (Question 2). ...
Ardua et Astra: On the Calculation of the Dates of the Rising and
... From our earliest texts onwards, we find classical authors referring to the time of year by means of the rising and setting of various stars and constellations. Hesiod encourages us to begin the harvest at the rising of the Pleiades, and to plough at their setting; Alcaeus encourages us to drink at ...
... From our earliest texts onwards, we find classical authors referring to the time of year by means of the rising and setting of various stars and constellations. Hesiod encourages us to begin the harvest at the rising of the Pleiades, and to plough at their setting; Alcaeus encourages us to drink at ...
103-122
... elements, Mg and Ca are best represented, with useful data also provided for Si. Unfortunately, the odd-even pair—Na and Al—are represented by just one or two lines and in only a few of the 36 stars. The value of the sample is that all but two of the stars belong to the halo; i.e., [Fe/H] < –1.0 wit ...
... elements, Mg and Ca are best represented, with useful data also provided for Si. Unfortunately, the odd-even pair—Na and Al—are represented by just one or two lines and in only a few of the 36 stars. The value of the sample is that all but two of the stars belong to the halo; i.e., [Fe/H] < –1.0 wit ...
preprint, pdf version - LESIA
... to their body size, which is usually related to their apparent sizes on the sky. Given the astrometric uncertainties in the star positions and the error in the TNO ephemeris, larger apparent diameters correspond to a higher probability of a successful prediction. Another selection criteria was the s ...
... to their body size, which is usually related to their apparent sizes on the sky. Given the astrometric uncertainties in the star positions and the error in the TNO ephemeris, larger apparent diameters correspond to a higher probability of a successful prediction. Another selection criteria was the s ...
here - NASA/IPAC Extragalactic Database
... plays an important role (Rivero Gonzáez et al. 2011). Of course, a significant problem occurs when one looks at O stars in other galaxies that are more metal-poor than the Milky Way where the various spectral standards have been defined. Even a high-luminosity O star in the SMC may fail to show He ...
... plays an important role (Rivero Gonzáez et al. 2011). Of course, a significant problem occurs when one looks at O stars in other galaxies that are more metal-poor than the Milky Way where the various spectral standards have been defined. Even a high-luminosity O star in the SMC may fail to show He ...
POSTERS SESSION I: Atmospheres of Massive Stars
... boundary, and the orbital elements of the system. ...
... boundary, and the orbital elements of the system. ...
Hipparcos distance estimates of the Ophiuchus and the Lupus cloud
... Meridian Catalogs), and the “Tycho-2 Spectra Type Catalog” ...
... Meridian Catalogs), and the “Tycho-2 Spectra Type Catalog” ...
SherwoodWA_1973redux - Edinburgh Research Archive
... 1970; Gottesman and Davis, 1970) found that the HII regions and blue supergiants (in associations) lie within the ...
... 1970; Gottesman and Davis, 1970) found that the HII regions and blue supergiants (in associations) lie within the ...
Late Summer Messier Objects
... M16 happens to be just across the constellation boundary into Serpens, but I think of all three objects as part of the Sagittarius Milky Way The three objects all fit together with M24 in the field of most hand-held binoculars, and my 70mm F/6.9 scope at lowest power is just able to fit the three ob ...
... M16 happens to be just across the constellation boundary into Serpens, but I think of all three objects as part of the Sagittarius Milky Way The three objects all fit together with M24 in the field of most hand-held binoculars, and my 70mm F/6.9 scope at lowest power is just able to fit the three ob ...
Heavy Element Abundances in Late-B and Early
... peculiar stars of the upper main sequence by up to a million times the solar system levels. Such enhancements are believed to result from atmospheric dynamics (i.e., diffusion) rather than scenarios that dredge up nuclearprocessed material to the surface or transfer processed material between binary ...
... peculiar stars of the upper main sequence by up to a million times the solar system levels. Such enhancements are believed to result from atmospheric dynamics (i.e., diffusion) rather than scenarios that dredge up nuclearprocessed material to the surface or transfer processed material between binary ...
Polaris
... nighttime sky, as is commonly believed. It’s only about 50th brightest. But you can find it easily, and, once you do, you’ll see it shining in the northern sky every night, from N. Hemisphere locations. ***In the Northern Hemisphere, the altitude of Polaris is equal to the observer’s latitude. In th ...
... nighttime sky, as is commonly believed. It’s only about 50th brightest. But you can find it easily, and, once you do, you’ll see it shining in the northern sky every night, from N. Hemisphere locations. ***In the Northern Hemisphere, the altitude of Polaris is equal to the observer’s latitude. In th ...
The Chemical Composition of Carbon-Rich, Very Metal
... Many observational and theoretical studies have been undertaken to clarify the formation and chemical evolution of the Galaxy, as well as the nature of stellar evolution at the earliest times. For this purpose, extensive surveys of metal-deficient stars have been carried out (e.g., the HK survey of ...
... Many observational and theoretical studies have been undertaken to clarify the formation and chemical evolution of the Galaxy, as well as the nature of stellar evolution at the earliest times. For this purpose, extensive surveys of metal-deficient stars have been carried out (e.g., the HK survey of ...
Protostellar/PMS Mass Infall Luminosity Problem
... Given the realistic comparison of the infall rates with the observed accretion rates of older PMS stars, we now estimate the accretion luminosity of protostars assuming the infall rate is equal to the accretion rate. ...
... Given the realistic comparison of the infall rates with the observed accretion rates of older PMS stars, we now estimate the accretion luminosity of protostars assuming the infall rate is equal to the accretion rate. ...
Fluorine abundances in dwarf stars of the solar neighbourhood⋆
... The aforementioned observational results combined with theoretical models currently indicate that all three suggested sources of fluorine contributed to the observed abundances of this element in different epochs of the evolution of the Galaxy (Renda et al. 2004; Kobayashi et al. 2011). However, the ...
... The aforementioned observational results combined with theoretical models currently indicate that all three suggested sources of fluorine contributed to the observed abundances of this element in different epochs of the evolution of the Galaxy (Renda et al. 2004; Kobayashi et al. 2011). However, the ...
My Constellation
... the same field. Both galaxies are elongated north-south; M65 has a tighter spiral and is perhaps the more noticeable. Õ NGC 3628, a galaxy seen edge-on. Actually, this is larger than either Messier object, but much dimmer because it is seen edge-on. Õ M95 (NGC 3351) and M96 (NGC 3368) form another n ...
... the same field. Both galaxies are elongated north-south; M65 has a tighter spiral and is perhaps the more noticeable. Õ NGC 3628, a galaxy seen edge-on. Actually, this is larger than either Messier object, but much dimmer because it is seen edge-on. Õ M95 (NGC 3351) and M96 (NGC 3368) form another n ...
silicon and oxygen abundances in planet-host stars
... however, given the known positive correlation between host star iron abundance and planet detection rate. Since planet hosts are found to have higher overall iron content (which serves as a proxy for overall metallicity) compared to non-hosts, they are indeed expected to have a higher content of oth ...
... however, given the known positive correlation between host star iron abundance and planet detection rate. Since planet hosts are found to have higher overall iron content (which serves as a proxy for overall metallicity) compared to non-hosts, they are indeed expected to have a higher content of oth ...
Mn, Cu, and Zn abundances in barium stars and their correlations
... of barium and normal giant stars, and present correlations between abundances contributed to different degrees by the weak-s, mains, and r-processes of neutron capture, between Fe-peak elements and heavy elements. Data from the literature are also considered in order to better study the abundance pat ...
... of barium and normal giant stars, and present correlations between abundances contributed to different degrees by the weak-s, mains, and r-processes of neutron capture, between Fe-peak elements and heavy elements. Data from the literature are also considered in order to better study the abundance pat ...
Star catalogue
A star catalogue, or star catalog, is an astronomical catalogue that lists stars. In astronomy, many stars are referred to simply by catalogue numbers. There are a great many different star catalogues which have been produced for different purposes over the years, and this article covers only some of the more frequently quoted ones. Star catalogues were compiled by many different ancient peoples, including the Babylonians, Greeks, Chinese, Persians, and Arabs. Most modern catalogues are available in electronic format and can be freely downloaded from NASA's Astronomical Data Center.Completeness and accuracy is described by the weakest apparent magnitude V (largest number) and the accuracy of the positions.