How to Build an Astrolabe
... Greece, were extensively developed in the medieval Islamic world and became the key astronomical instrument of the western middle ages. When mapping the heavens astronomers assume that the stars seen in the night sky are all at an equal distance from the earth, fixed on the inside of an enormous sph ...
... Greece, were extensively developed in the medieval Islamic world and became the key astronomical instrument of the western middle ages. When mapping the heavens astronomers assume that the stars seen in the night sky are all at an equal distance from the earth, fixed on the inside of an enormous sph ...
Sky Watcher - Boise Astronomical Society
... Jupiter is approaching the sun and will disappear from view by the end of June. As it approaches the horizon, it makes a close approach to Mercury on the evening of the 24 th. That evening, look for bright Jupiter low in the west and fainter Mercury lower in the northwest. Mercury and Jupiter will b ...
... Jupiter is approaching the sun and will disappear from view by the end of June. As it approaches the horizon, it makes a close approach to Mercury on the evening of the 24 th. That evening, look for bright Jupiter low in the west and fainter Mercury lower in the northwest. Mercury and Jupiter will b ...
1 Astrobiologically Interesting Stars within 10
... may have outlasted their usefulness as abodes of life, if the luminosity increase sustained from zero age to their present evolutionary status surpasses the capability of the planetary thermo-regulating carbonate-silicate cycle. This situation is dependent upon planetary location inside the CHZ, yet ...
... may have outlasted their usefulness as abodes of life, if the luminosity increase sustained from zero age to their present evolutionary status surpasses the capability of the planetary thermo-regulating carbonate-silicate cycle. This situation is dependent upon planetary location inside the CHZ, yet ...
Rotation Periods of Wide Binaries in the Kepler Field
... field of the Kepler spacecraft I identified 93 likely binary systems. A comparison of their rotation periods is a test of the gyrochronology concept. To find their periods I calculated the autocorrelation function of the Kepler mission photometry for each star. In most systems for which good periods ...
... field of the Kepler spacecraft I identified 93 likely binary systems. A comparison of their rotation periods is a test of the gyrochronology concept. To find their periods I calculated the autocorrelation function of the Kepler mission photometry for each star. In most systems for which good periods ...
Discovery of extremely lead-rich subdwarfs: does heavy metal signal
... Hot subdwarfs represent a group of low-mass helium-burning stars formed through binarystar interactions and include some of the most chemically peculiar stars in the Galaxy. Stellar evolution theory suggests that they should have helium-rich atmospheres but, because radiation causes hydrogen to diff ...
... Hot subdwarfs represent a group of low-mass helium-burning stars formed through binarystar interactions and include some of the most chemically peculiar stars in the Galaxy. Stellar evolution theory suggests that they should have helium-rich atmospheres but, because radiation causes hydrogen to diff ...
Galaxies - Stockton University
... They are flashes of gamma rays emanating from seemingly random places in deep space at random times. The duration of a gamma-ray burst is typically a few seconds, but can range from a few milliseconds to several minutes, and the initial burst is usually followed by a longer-lived "afterglow" emittin ...
... They are flashes of gamma rays emanating from seemingly random places in deep space at random times. The duration of a gamma-ray burst is typically a few seconds, but can range from a few milliseconds to several minutes, and the initial burst is usually followed by a longer-lived "afterglow" emittin ...
Stellar populations
... • Typically they contain a few hundred stars • The stars are coeval (of same age), at essentially same distance and of same metallicity • There is a spread in star masses (given by IMF) ...
... • Typically they contain a few hundred stars • The stars are coeval (of same age), at essentially same distance and of same metallicity • There is a spread in star masses (given by IMF) ...
WORD - Astrophysics
... overcome crowding, and a 100m class telescope is required to study the brighter galaxies at their half-light radius - without it work is limited to the less representative outer regions where crowding is less of an issue. The more luminous elliptical ...
... overcome crowding, and a 100m class telescope is required to study the brighter galaxies at their half-light radius - without it work is limited to the less representative outer regions where crowding is less of an issue. The more luminous elliptical ...
The Stars - Springer
... Y stars are sub-brown dwarfs. As of the time of writing, no Y objects have yet been discovered! The star types R, N and S actually overlap class M, and so R and N have been reclassified as C-type stars, the C standing for carbon stars. Complicated, isn’t it! ...
... Y stars are sub-brown dwarfs. As of the time of writing, no Y objects have yet been discovered! The star types R, N and S actually overlap class M, and so R and N have been reclassified as C-type stars, the C standing for carbon stars. Complicated, isn’t it! ...
Neon abundances - UCL Astrophysics Group
... In many cases, the lines are so weak that only upper limits can be established. The most extreme example found is y Her with an underabundance of at least 1.5 dex. These underabundances are qualitatively expected from radiative acceleration calculations, which show that Ne has a very small radiative ...
... In many cases, the lines are so weak that only upper limits can be established. The most extreme example found is y Her with an underabundance of at least 1.5 dex. These underabundances are qualitatively expected from radiative acceleration calculations, which show that Ne has a very small radiative ...
As far as - Sangeeta Malhotra
... the two effects will be valuable. Because their spectra give us accurate distances, we can see that these galaxies are distributed in clusters all the way out to the highest redshift visible. For example, one cluster, or “wall,” of galaxies lies at a distance of 6 billion light-years (redshift 0.67) ...
... the two effects will be valuable. Because their spectra give us accurate distances, we can see that these galaxies are distributed in clusters all the way out to the highest redshift visible. For example, one cluster, or “wall,” of galaxies lies at a distance of 6 billion light-years (redshift 0.67) ...
Cassiopeia (constellation)
Cassiopeia is a constellation in the northern sky, named after the vain queen Cassiopeia in Greek mythology, who boasted about her unrivalled beauty. Cassiopeia was one of the 48 constellations listed by the 2nd-century Greek astronomer Ptolemy, and it remains one of the 88 modern constellations today. It is easily recognizable due to its distinctive 'M' shape when in upper culmination but in higher northern locations when near lower culminations in spring and summer it has a 'W' shape, formed by five bright stars. It is bordered by Andromeda to the south, Perseus to the southeast, and Cepheus to the north. It is opposite the Big Dipper.In northern locations above 34ºN latitude it is visible year-round and in the (sub)tropics it can be seen at its clearest from September to early November in its characteristic 'M' shape. Even in low southern latitudes below 25ºS is can be seen low in the North.