Astronomy 112 - Solar Physics and Space Weather
... (i.e. curve) for each of four objects in the solar system: Mercury, Mars, the Moon and the Earth. You will use computer digitized images and a special tool designed to facilitate the taking of these measurements. You will also have access to an Excel file which contains a worksheet, and a separate g ...
... (i.e. curve) for each of four objects in the solar system: Mercury, Mars, the Moon and the Earth. You will use computer digitized images and a special tool designed to facilitate the taking of these measurements. You will also have access to an Excel file which contains a worksheet, and a separate g ...
Where stars form: inside-out growth and coherent star formation from
... spatially resolved spectroscopy. Because this spectrograph is slitless, it provides a spectrum for every object in its field of view. This means that for every object its field of view and wavelength coverage, the grism can be used to create a high spatial resolution emission line map. The 3D-HST le ...
... spatially resolved spectroscopy. Because this spectrograph is slitless, it provides a spectrum for every object in its field of view. This means that for every object its field of view and wavelength coverage, the grism can be used to create a high spatial resolution emission line map. The 3D-HST le ...
Statistical properties of a sample of periodically variable B-type supergiants ⋆
... Waelkens et al. (1998) positioned the new periodic B supergiants in the HR diagram on the basis of multicolour photometric calibrations (accurate parallaxes are not available) and found them to be situated between the SPBs and previously known α Cyg-type variables (see their Fig. 2). Oscillations we ...
... Waelkens et al. (1998) positioned the new periodic B supergiants in the HR diagram on the basis of multicolour photometric calibrations (accurate parallaxes are not available) and found them to be situated between the SPBs and previously known α Cyg-type variables (see their Fig. 2). Oscillations we ...
A physical interpretation of the `red Sirius` anomaly
... since leaving the main sequence. The lack of any detectable nebular matter in the vicinity of the Sirius system (Bruhweiler, Kondo & Sion 1986; Bonnet-Bidaud & Gry 1991) is inconsistent with core±envelope separation as recently as , 2 103 yr ago. The time-scale for dissipation of an ejected envelo ...
... since leaving the main sequence. The lack of any detectable nebular matter in the vicinity of the Sirius system (Bruhweiler, Kondo & Sion 1986; Bonnet-Bidaud & Gry 1991) is inconsistent with core±envelope separation as recently as , 2 103 yr ago. The time-scale for dissipation of an ejected envelo ...
Astronomical Circumstances
... may have much different fates. For example, small stars Once its hydrogen fuel is mostly consumed, a medium do not go through the giant stage but simply collapse sized star like our own will expand outward to become a into white dwarves after the main sequence. The death red giant. During this stag ...
... may have much different fates. For example, small stars Once its hydrogen fuel is mostly consumed, a medium do not go through the giant stage but simply collapse sized star like our own will expand outward to become a into white dwarves after the main sequence. The death red giant. During this stag ...
Radiative winds, accretion disks and massive stars physics using
... opacity source in O stars is electron scattering. Does this drive the wind? If the force from electron scattering were to exceed gravity (known as the Eddington limit) the surface of a star could not remain bound and the star would blow itself apart. • Instead, stellar winds are rather stable, using ...
... opacity source in O stars is electron scattering. Does this drive the wind? If the force from electron scattering were to exceed gravity (known as the Eddington limit) the surface of a star could not remain bound and the star would blow itself apart. • Instead, stellar winds are rather stable, using ...
The Evolution of Molecular Clouds
... than the Galactic average, yields a formation timescale for molecular clouds of about 50 Myr (Larson 1991a, 1992b). Note that this estimated formation time is not much longer than the cloud lifetime of ∼ 20 Myr (Section 2); thus the formation of molecular clouds must itself be a rather rapid process ...
... than the Galactic average, yields a formation timescale for molecular clouds of about 50 Myr (Larson 1991a, 1992b). Note that this estimated formation time is not much longer than the cloud lifetime of ∼ 20 Myr (Section 2); thus the formation of molecular clouds must itself be a rather rapid process ...
Simulations of the galaxy population constrained by observations
... computer time, allowing the different modelling assumptions to be tested by detailed comparison with the relevant observational data. At present, semi-analytic methods are the only technique able to simulate the evolution of the galaxy population on a scale and with a precision which allows detailed ...
... computer time, allowing the different modelling assumptions to be tested by detailed comparison with the relevant observational data. At present, semi-analytic methods are the only technique able to simulate the evolution of the galaxy population on a scale and with a precision which allows detailed ...
SAGE_prop
... galactic evolution. Crucial elements of the picture concern the levels of activity in main sequence stars and the resulting stellar winds which can directly affect planetary environments on a range of timescales. In addition, stellar winds control the flow of material and flux of cosmic rays from th ...
... galactic evolution. Crucial elements of the picture concern the levels of activity in main sequence stars and the resulting stellar winds which can directly affect planetary environments on a range of timescales. In addition, stellar winds control the flow of material and flux of cosmic rays from th ...
PP Chapter 28 Text
... Life cycle of stars: • Begins as a nebula • Advances to a protostar • Becomes a star when fusion in its core occurs Depending on its mass, the star may become a red giant and then burn out to become a white dwarf. ...
... Life cycle of stars: • Begins as a nebula • Advances to a protostar • Becomes a star when fusion in its core occurs Depending on its mass, the star may become a red giant and then burn out to become a white dwarf. ...
IAC_L2_thindisk
... • the thick disk stars are all old (> 10 Gyr) and have abundances between about -0.3 to -1.2, with a metal-weak tail extending down to about -2.0. • the thick disk stars form an -enhanced sequence in the [ /Fe] vs [Fe/H]. Because of operational difficulties in assigning individual stars kinematica ...
... • the thick disk stars are all old (> 10 Gyr) and have abundances between about -0.3 to -1.2, with a metal-weak tail extending down to about -2.0. • the thick disk stars form an -enhanced sequence in the [ /Fe] vs [Fe/H]. Because of operational difficulties in assigning individual stars kinematica ...
PH607lec08
... they occur in; if so then bars are the most flattened triaxial systems known Bars in edge-on galaxies are hard to detect photometrically; however, kinematic signatures of barred potentials have been used to infer their presence in some edge-on systems. What is noteworthy is that such edgeon bars ap ...
... they occur in; if so then bars are the most flattened triaxial systems known Bars in edge-on galaxies are hard to detect photometrically; however, kinematic signatures of barred potentials have been used to infer their presence in some edge-on systems. What is noteworthy is that such edgeon bars ap ...
15_1655_Iaria_Presence_of_a_Third_body
... We folded the RXTE/ASM light curves in the 3-5 and 5-12.2 keV energy band. The ASM light curve covers from 1996 Sep 01 to 2011 Oct 31. If our ephemeris is correct we expect the hardness ratio should be larger at phase 0 because the larger photoelectric absorption during the dip. Left: Hu’s ephemeris ...
... We folded the RXTE/ASM light curves in the 3-5 and 5-12.2 keV energy band. The ASM light curve covers from 1996 Sep 01 to 2011 Oct 31. If our ephemeris is correct we expect the hardness ratio should be larger at phase 0 because the larger photoelectric absorption during the dip. Left: Hu’s ephemeris ...
Stars & Galaxies - newmanlib.ibri.org
... • 'Galaxies' are what we call the huge star clusters that inhabit our universe. • These clusters range in size from ten million stars to about a trillion. • The galaxy in which we live is popularly called the 'Milky Way,' because that is what it looked like to the ancients. ...
... • 'Galaxies' are what we call the huge star clusters that inhabit our universe. • These clusters range in size from ten million stars to about a trillion. • The galaxy in which we live is popularly called the 'Milky Way,' because that is what it looked like to the ancients. ...
FIELD ASTRONOMY
... The solar day, or the time corresponding to one rotation of the earth with respect to the direction of the sun, is the most natural unit of time for ordinary purposes. If time was regulated by stars, sidereal noon would occur at night during half the year. For obvious reasons, this would not be a sa ...
... The solar day, or the time corresponding to one rotation of the earth with respect to the direction of the sun, is the most natural unit of time for ordinary purposes. If time was regulated by stars, sidereal noon would occur at night during half the year. For obvious reasons, this would not be a sa ...
Astrometry of Asteroids
... In this exercise you will be using images of the sky to find asteroids and measure their positions. Asteroids are small rocky objects that orbit the sun just like planets. They are located predominately between the orbit of Mars and Jupiter, about 2.8 Astronomical Units from the sun. Asteroids do or ...
... In this exercise you will be using images of the sky to find asteroids and measure their positions. Asteroids are small rocky objects that orbit the sun just like planets. They are located predominately between the orbit of Mars and Jupiter, about 2.8 Astronomical Units from the sun. Asteroids do or ...
Astrometry of Asteroids
... In this exercise you will be using images of the sky to find asteroids and measure their positions. Asteroids are small rocky objects that orbit the sun just like planets. They are located predominately between the orbit of Mars and Jupiter, about 2.8 Astronomical Units from the sun. Asteroids do or ...
... In this exercise you will be using images of the sky to find asteroids and measure their positions. Asteroids are small rocky objects that orbit the sun just like planets. They are located predominately between the orbit of Mars and Jupiter, about 2.8 Astronomical Units from the sun. Asteroids do or ...
IK Pegasi
IK Pegasi (or HR 8210) is a binary star system in the constellation Pegasus. It is just luminous enough to be seen with the unaided eye, at a distance of about 150 light years from the Solar System.The primary (IK Pegasi A) is an A-type main-sequence star that displays minor pulsations in luminosity. It is categorized as a Delta Scuti variable star and it has a periodic cycle of luminosity variation that repeats itself about 22.9 times per day. Its companion (IK Pegasi B) is a massive white dwarf—a star that has evolved past the main sequence and is no longer generating energy through nuclear fusion. They orbit each other every 21.7 days with an average separation of about 31 million kilometres, or 19 million miles, or 0.21 astronomical units (AU). This is smaller than the orbit of Mercury around the Sun.IK Pegasi B is the nearest known supernova progenitor candidate. When the primary begins to evolve into a red giant, it is expected to grow to a radius where the white dwarf can accrete matter from the expanded gaseous envelope. When the white dwarf approaches the Chandrasekhar limit of 1.44 solar masses (M☉), it may explode as a Type Ia supernova.