starry night companion
... privilege of such a view. Standing under a canopy of stars on a clear night, we’ve had to take on faith what astronomers have told us. Starry Night, whose many features are described in this book, changes all that. John Mosley’s clearly written and engaging text is filled with details about this rem ...
... privilege of such a view. Standing under a canopy of stars on a clear night, we’ve had to take on faith what astronomers have told us. Starry Night, whose many features are described in this book, changes all that. John Mosley’s clearly written and engaging text is filled with details about this rem ...
celestial navigation heaven`s guide for mere
... and dust around the stars may be residual material from their formation or simply interstellar clouds the cluster is passing through. All stars are different in terms of size, colour and brightness as mentioned in the earlier paragraphs. These characteristics differ due to the stars’ differing mass. ...
... and dust around the stars may be residual material from their formation or simply interstellar clouds the cluster is passing through. All stars are different in terms of size, colour and brightness as mentioned in the earlier paragraphs. These characteristics differ due to the stars’ differing mass. ...
Chemical composition of 90 F and G disk dwarfs
... Alonso et al. (1996) and the gravity from Hipparcos parallax lead to slight deviations from the selection criteria for some stars. Based on the above selection, 104 F and G stars were observed, but 3 high-rotation (V sin i ≥ 25 km s−1 ) stars and 9 double-line spectroscopic binaries were excluded fr ...
... Alonso et al. (1996) and the gravity from Hipparcos parallax lead to slight deviations from the selection criteria for some stars. Based on the above selection, 104 F and G stars were observed, but 3 high-rotation (V sin i ≥ 25 km s−1 ) stars and 9 double-line spectroscopic binaries were excluded fr ...
148 Jun - British Astronomical Association
... both Mount Wilson and Siding Spring Observatories, he will be best remembered for his support of the amateur fraternity and his lifetime total of 157,056 observations (all but 5 being visual!). Tom joined the AAVSO in 1945 at the age of 17 and took advantage of his location after moving to Australia ...
... both Mount Wilson and Siding Spring Observatories, he will be best remembered for his support of the amateur fraternity and his lifetime total of 157,056 observations (all but 5 being visual!). Tom joined the AAVSO in 1945 at the age of 17 and took advantage of his location after moving to Australia ...
... – Census of galaxies nearby: Most are dim dwarf E and dwarf Irr sparsely populated with stars – Census of distant galaxies: In clusters, 60% of members are spirals and S0, while in sparsely populated regions it is 80% – Early (very young) galaxies are much smaller than Milky Way – merging of these s ...
chapter 15 navigational astronomy
... superior planet is near conjunction, it rises and sets approximately with the Sun and is thus lost in the Sun’s glare. Gradually it becomes visible in the early morning sky before sunrise. From day to day, it rises and sets earlier, becoming increasingly visible through the late night hours until da ...
... superior planet is near conjunction, it rises and sets approximately with the Sun and is thus lost in the Sun’s glare. Gradually it becomes visible in the early morning sky before sunrise. From day to day, it rises and sets earlier, becoming increasingly visible through the late night hours until da ...
Navigating the Night Sky Checklist
... appears to move steadily eastward along the ecliptic, through the constellations of the zodiac. As Earth orbits the Sun, we see the Sun against the background of different zodiac constellations at different times of year. For example, on August 21 the Sun appears to be in Leo, because it is between ...
... appears to move steadily eastward along the ecliptic, through the constellations of the zodiac. As Earth orbits the Sun, we see the Sun against the background of different zodiac constellations at different times of year. For example, on August 21 the Sun appears to be in Leo, because it is between ...
Navigation: The Mariner`s Quadrant
... edges for sighting. The only scale needed was the degree marks on the curved edge. It was light and easy to handle. ...
... edges for sighting. The only scale needed was the degree marks on the curved edge. It was light and easy to handle. ...
Evidence for the Tidal Destruction of Hot Jupiters by Subgiant Stars
... Tidal transfer of angular momentum is expected to cause hot Jupiters to spiral into their host stars. Although the timescale for orbital decay is very uncertain, it should be faster for systems with larger and more evolved stars. Indeed, it is well established that hot Jupiters are found less freque ...
... Tidal transfer of angular momentum is expected to cause hot Jupiters to spiral into their host stars. Although the timescale for orbital decay is very uncertain, it should be faster for systems with larger and more evolved stars. Indeed, it is well established that hot Jupiters are found less freque ...
A Digital Spectral Classification Atlas
... The MK Spectral classification system was founded by W.W. Morgan and P.C. Keenan in the year 1943, with the publication of the first photographic spectral classification atlas, An Atlas of Stellar Spectra (Morgan, Keenan & Kelleman, 1943). Since that time, the MK system has been extensively revised ...
... The MK Spectral classification system was founded by W.W. Morgan and P.C. Keenan in the year 1943, with the publication of the first photographic spectral classification atlas, An Atlas of Stellar Spectra (Morgan, Keenan & Kelleman, 1943). Since that time, the MK system has been extensively revised ...
1998 - Universitäts-Sternwarte München
... or the very spectacular supernova events. Nowadays, it is therefore no surprise that the ancient stars of the Galactic halo are found to be metal-poor objects – as opposed to the understanding when they were first analyzed in the 1950s. Interestingly, these stars also reveal a very different kinemat ...
... or the very spectacular supernova events. Nowadays, it is therefore no surprise that the ancient stars of the Galactic halo are found to be metal-poor objects – as opposed to the understanding when they were first analyzed in the 1950s. Interestingly, these stars also reveal a very different kinemat ...
The ages of pre-main-sequence stars
... birthline. Unfortunately, this apparent birthline is not the place where stars are born, and so an age measured from a zero-age deuterium-burning sequence is too young by an unknown amount which is normally at least as much as the deuterium-burning lifetime. D'Antona & Mazzitelli (1994) take another ...
... birthline. Unfortunately, this apparent birthline is not the place where stars are born, and so an age measured from a zero-age deuterium-burning sequence is too young by an unknown amount which is normally at least as much as the deuterium-burning lifetime. D'Antona & Mazzitelli (1994) take another ...
On the nature of sn stars. I. A detailed abundance study
... sharp Balmer lines, sharp metallic lines (C II, Si II, Ca II, Ti II, Fe II), and broad coreless He I lines. Some of the sn stars seem to be related to CP stars. Initially Abt & Levato proposed a shell-like nature to explain the sn stars, although this scenario was subsequently questioned. There is n ...
... sharp Balmer lines, sharp metallic lines (C II, Si II, Ca II, Ti II, Fe II), and broad coreless He I lines. Some of the sn stars seem to be related to CP stars. Initially Abt & Levato proposed a shell-like nature to explain the sn stars, although this scenario was subsequently questioned. There is n ...
Discovery of White Dwarfs—1 Oct • Adams’ discovery
... • If the apparent mag changes by −2.5, the flux is brighter by a factor of 10. • Fluxes and magnitudes of two stars A and B ...
... • If the apparent mag changes by −2.5, the flux is brighter by a factor of 10. • Fluxes and magnitudes of two stars A and B ...
Observational studies of stellar rotation
... period Prot . This technique has the advantage over spectroscopy of yielding a measurement of the stellar rotation rate that is free of geometric effects and is straighforwardly converted to angular velocity, Ω = 2π/Prot . However, this is at the expense of requiring intense photometric monitoring o ...
... period Prot . This technique has the advantage over spectroscopy of yielding a measurement of the stellar rotation rate that is free of geometric effects and is straighforwardly converted to angular velocity, Ω = 2π/Prot . However, this is at the expense of requiring intense photometric monitoring o ...
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.