The Official Magazine of the University Of St Andrews Astronomical Society 1
... Solar Flares and Planetary Migration The vast majority of exoplanets found have been large gas giants, close to their parent star, with orbital periods of only a few days. Our gas giants, however, are orders of magnitude more distant from the sun than typical exoplanets are from their stars. Why is ...
... Solar Flares and Planetary Migration The vast majority of exoplanets found have been large gas giants, close to their parent star, with orbital periods of only a few days. Our gas giants, however, are orders of magnitude more distant from the sun than typical exoplanets are from their stars. Why is ...
Pulsar slow glitches in a solid quark star model
... pulsar is the change in its period known as slow glitches. Different from the typical feature of glitch phenomenon of other pulsars, this pulsar shows glitches that have rather slow increase in spin frequency, with a time scale of 200-300 days (while the normal glitches experience this process much ...
... pulsar is the change in its period known as slow glitches. Different from the typical feature of glitch phenomenon of other pulsars, this pulsar shows glitches that have rather slow increase in spin frequency, with a time scale of 200-300 days (while the normal glitches experience this process much ...
ONE- AND MULTI- ZONE MODELS: Chemical properties
... Lynden-Bell, 1975 Tinsley, 1980a Chiosi, 1981), i.e. models in which the total mass of the disk is let increase with time at a suitable rate starting from a much lower value. With the current law of star formation (proportional to the gas mass) the competition between gas accretion by infall and g ...
... Lynden-Bell, 1975 Tinsley, 1980a Chiosi, 1981), i.e. models in which the total mass of the disk is let increase with time at a suitable rate starting from a much lower value. With the current law of star formation (proportional to the gas mass) the competition between gas accretion by infall and g ...
Part IV: Stars
... by comparing their predictions for the radius, surface temperature, and luminosity, as well as other observable parameters generated by studying helioseismology. Helioseismology allows us to probe the conditions in the solar interior. The models make testable predictions that allow us to explain the ...
... by comparing their predictions for the radius, surface temperature, and luminosity, as well as other observable parameters generated by studying helioseismology. Helioseismology allows us to probe the conditions in the solar interior. The models make testable predictions that allow us to explain the ...
Chapter 15 Observational Evidence for Black Holes
... 1. In the early 1970s an X-ray source was discovered in Cygnus and designated Cygnus X-1. 2. In 1972, a radio source was found in the same general area and identified optically with a blue supergiant star called HDE226868. Correlations in radio activity of HDE226868 and X-ray activity of Cygnus X-1 ...
... 1. In the early 1970s an X-ray source was discovered in Cygnus and designated Cygnus X-1. 2. In 1972, a radio source was found in the same general area and identified optically with a blue supergiant star called HDE226868. Correlations in radio activity of HDE226868 and X-ray activity of Cygnus X-1 ...
UNIFIED PICTURE OF LARGE AND SMALL SCALE: MICRO
... • Using the Kepler satellite data we searched for superflares on solar type stars (G type main sequence stars) and discovered 420 events. • More than 50 superflares are found to occur on slowly rotating stars like our Sun (its period is 25 days). • We conclude that superflares can occur on our Sun a ...
... • Using the Kepler satellite data we searched for superflares on solar type stars (G type main sequence stars) and discovered 420 events. • More than 50 superflares are found to occur on slowly rotating stars like our Sun (its period is 25 days). • We conclude that superflares can occur on our Sun a ...
JHK standard stars for large telescopes: the UKIRT Fundamental
... In 1990 a programme was initiated at UKIRT to construct a set of standard stars faint enough to be observable with the IRCAM imager in standard observing mode. A list of stars was selected from Landolt’s (1983) equatorial UBVRI standards and the compilation of potential Hubble Space Telescope (HST ) ...
... In 1990 a programme was initiated at UKIRT to construct a set of standard stars faint enough to be observable with the IRCAM imager in standard observing mode. A list of stars was selected from Landolt’s (1983) equatorial UBVRI standards and the compilation of potential Hubble Space Telescope (HST ) ...
the UKIRT Fundamental and Extended lists
... In 1990 a programme was initiated at UKIRT to construct a set of standard stars faint enough to be observable with the IRCAM imager in standard observing mode. A list of stars was selected from Landolt’s (1983) equatorial UBVRI standards and the compilation of potential Hubble Space Telescope (HST ) ...
... In 1990 a programme was initiated at UKIRT to construct a set of standard stars faint enough to be observable with the IRCAM imager in standard observing mode. A list of stars was selected from Landolt’s (1983) equatorial UBVRI standards and the compilation of potential Hubble Space Telescope (HST ) ...
the origin of the hubble sequence - Yale Astronomy
... momentum and thus allowing the formation of a dense and slowly rotating spheroid (Lake and Carlberg 1988a). Simulations of the collapse of systems of stars have in fact shown that gravitational interactions in a clumpy or inhomogeneous system tend quite generally to produce a structure like that of ...
... momentum and thus allowing the formation of a dense and slowly rotating spheroid (Lake and Carlberg 1988a). Simulations of the collapse of systems of stars have in fact shown that gravitational interactions in a clumpy or inhomogeneous system tend quite generally to produce a structure like that of ...
Exploration géochimique du Système Solaire
... Seismic parameters determined from asteroseismology for sdB stars are both precise, accurate, and robust again model uncertainties The best-fit (optimal) model is the most representative model of the star ...
... Seismic parameters determined from asteroseismology for sdB stars are both precise, accurate, and robust again model uncertainties The best-fit (optimal) model is the most representative model of the star ...
Roche accretion of stars close to massive black holes
... The gas flowing through L1 will generally have enough angular momentum to form a torus orbiting the hole. A hotspot will be formed where the stream hits the disc. In addition, it is quite possible that one or two spiral arm shock waves will be created in the disc. The hotspot and shocks will orbit t ...
... The gas flowing through L1 will generally have enough angular momentum to form a torus orbiting the hole. A hotspot will be formed where the stream hits the disc. In addition, it is quite possible that one or two spiral arm shock waves will be created in the disc. The hotspot and shocks will orbit t ...
Chapter 9 powerpoint presentation
... where ’ is the vertical optical depth. The frequency dependence in is taken care of by the Rossland Mean opacity. Take two moments of the R.T.E. which means integrate over solid angle, d, to get the first moment. Then multiply by Cos and integrate again to get the second moment. After some al ...
... where ’ is the vertical optical depth. The frequency dependence in is taken care of by the Rossland Mean opacity. Take two moments of the R.T.E. which means integrate over solid angle, d, to get the first moment. Then multiply by Cos and integrate again to get the second moment. After some al ...
The Star Finder Book - Starpath School of Navigation
... the subject at hand, and improving dead reckoning procedure is easily accommodated underway without special training. The problem with cloudy skies we cover here is that of identifying unknown stars in isolated patches of clear sky. Such stars may be in view for a few minutes only, just long enough ...
... the subject at hand, and improving dead reckoning procedure is easily accommodated underway without special training. The problem with cloudy skies we cover here is that of identifying unknown stars in isolated patches of clear sky. Such stars may be in view for a few minutes only, just long enough ...
Chapter 13 Measuring the properties of stars
... Which of the following statements would explain the fact that larger molecules, such as amino acids, do not produce spectral lines in the OBAFGKM classification? A. Larger molecules require higher temperatures to show absorption lines. B. The spectra of hydrogen and helium are sufficient to classif ...
... Which of the following statements would explain the fact that larger molecules, such as amino acids, do not produce spectral lines in the OBAFGKM classification? A. Larger molecules require higher temperatures to show absorption lines. B. The spectra of hydrogen and helium are sufficient to classif ...
CAPSTONE-poster
... The famous astronomer William Herschel discovered the first planetary nebulae called Dumbbell nebula (M27) in the 1870’s. The name was given because he found an apparent similarity to the disk of Uranus. So far, there are 2,000 planetary nebulae in our Milky Way galaxy and their average lifespan is ...
... The famous astronomer William Herschel discovered the first planetary nebulae called Dumbbell nebula (M27) in the 1870’s. The name was given because he found an apparent similarity to the disk of Uranus. So far, there are 2,000 planetary nebulae in our Milky Way galaxy and their average lifespan is ...
Light n-Capture Element Abundances in Metal
... to the elemental abundances. The turn-on time of these events will eliminate certain objects, such as low mass stars, as potential early contributors to the r-process. The abundances of Y and Zr are plotted versus sprocess element Ba to observe any correlations. By comparison of these ratios, any in ...
... to the elemental abundances. The turn-on time of these events will eliminate certain objects, such as low mass stars, as potential early contributors to the r-process. The abundances of Y and Zr are plotted versus sprocess element Ba to observe any correlations. By comparison of these ratios, any in ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.