Doppler imaging of stellar surfaces
... the standard calibration of photometry against standard stars is huge. Thus, in practice, the logarithm of continuum flux at band centre is calibrated against the standard magnitudes for stars of the same effective temperatures as the atmospheres provided to the code for the computation of the tabul ...
... the standard calibration of photometry against standard stars is huge. Thus, in practice, the logarithm of continuum flux at band centre is calibrated against the standard magnitudes for stars of the same effective temperatures as the atmospheres provided to the code for the computation of the tabul ...
Determining the inclination of the rotation axis of a sun-like Star
... rotation axis of a pulsating Sun-like star and the line of sight. A knowledge of i is important not just for obtaining improved stellar parameters, but also in order to determine the true masses of extrasolar planets detected from the radial velocity shifts of their central stars. By means of Monte ...
... rotation axis of a pulsating Sun-like star and the line of sight. A knowledge of i is important not just for obtaining improved stellar parameters, but also in order to determine the true masses of extrasolar planets detected from the radial velocity shifts of their central stars. By means of Monte ...
Milky Way
... •When a low mass object orbits a high mass object, there is a simple relationship between the distance and the velocity: ...
... •When a low mass object orbits a high mass object, there is a simple relationship between the distance and the velocity: ...
The star formation histories of two northern LMC fields
... formation history is also correct for two other outer LMC fields. It has also been hinted that the star formation rates may have begun to decrease during the past Gyr. Olsen (1999) studied the HST field surrounding NGC 1754, which also lies in the northern part of the disc, as well as the fields sur ...
... formation history is also correct for two other outer LMC fields. It has also been hinted that the star formation rates may have begun to decrease during the past Gyr. Olsen (1999) studied the HST field surrounding NGC 1754, which also lies in the northern part of the disc, as well as the fields sur ...
No Slide Title
... The structure and behavior of the atmosphere around the tropopause are now known to be more complex than previously thought. Exchange of material between the troposphere and the stratosphere takes place not only through ascent through the tropical tropopause, but also through transports along isentr ...
... The structure and behavior of the atmosphere around the tropopause are now known to be more complex than previously thought. Exchange of material between the troposphere and the stratosphere takes place not only through ascent through the tropical tropopause, but also through transports along isentr ...
norfolk skies - Norfolk Astronomical Society
... just south of Sirius, in the constellation pf Canis Major. It's a very impressive little group, with about 3040 little 10th magnitude stars, all bunched up around this bright 4th magnitude star. A very attractive cluster, even in a small telescope, and it's magnificent in a larger one. It's known as ...
... just south of Sirius, in the constellation pf Canis Major. It's a very impressive little group, with about 3040 little 10th magnitude stars, all bunched up around this bright 4th magnitude star. A very attractive cluster, even in a small telescope, and it's magnificent in a larger one. It's known as ...
Stars
... Effects of its low metallicity: GN93: convective core, sensitivity to core overshoot; need for intermediate to large core overshoot ...
... Effects of its low metallicity: GN93: convective core, sensitivity to core overshoot; need for intermediate to large core overshoot ...
The photometric system of the One
... are shown as red dots in the left panel of Figure 2 (the standard deviation is represented by error bars). The seeing condition has been stable in the past six years. The small variation is probably due to a sampling bias, because the criteria for using the telescope for observations has changed fro ...
... are shown as red dots in the left panel of Figure 2 (the standard deviation is represented by error bars). The seeing condition has been stable in the past six years. The small variation is probably due to a sampling bias, because the criteria for using the telescope for observations has changed fro ...
ON STARS, THEIR EVOLUTION AND THEIR STABILITY
... is the essence of Eddington’s paradox as formulated by Fowler. And Fowler resolved this paradox in 1926 in a paper’ entitled ‘Dense Matter’ - one of the great landmark papers in the realm ofstellar structure: in it the notions of Fermi statistics and of electron degeneracy are introduced for the fir ...
... is the essence of Eddington’s paradox as formulated by Fowler. And Fowler resolved this paradox in 1926 in a paper’ entitled ‘Dense Matter’ - one of the great landmark papers in the realm ofstellar structure: in it the notions of Fermi statistics and of electron degeneracy are introduced for the fir ...
Introduction: The History and Technique of Stellar Classification
... of wavelength is 3900 Å to 4500 Å (x axis). The intensity of each spectrum (y axis) is normalized, i.e., it has been multiplied by a constant so that the trace spectrum fits into the picture with a value of 1.0 at maximum intensity, and 0 for no light at all. The spectral type of a star allows an as ...
... of wavelength is 3900 Å to 4500 Å (x axis). The intensity of each spectrum (y axis) is normalized, i.e., it has been multiplied by a constant so that the trace spectrum fits into the picture with a value of 1.0 at maximum intensity, and 0 for no light at all. The spectral type of a star allows an as ...
Local Horizon View
... latitude, the pole star is at altitude 45 degrees as shown to the right. We can see that when we look up. This diagram shows that the altitude of Polaris above the horizon is the same as the observer's latitude. Note that the lines drawn to Polaris are parallel because Polaris is very far away. The ...
... latitude, the pole star is at altitude 45 degrees as shown to the right. We can see that when we look up. This diagram shows that the altitude of Polaris above the horizon is the same as the observer's latitude. Note that the lines drawn to Polaris are parallel because Polaris is very far away. The ...
Exoplanet Discovery
... planets (astroseismology) and atmospheric composition – what will we find? ...
... planets (astroseismology) and atmospheric composition – what will we find? ...
Neutron Stars and Black Holes
... 17. What observational evidence do we have that stellar death black holes really exist? a. Hollowed-out green spheres are sucking up matter in star forming regions and emitting gamma rays. b. Some X-ray binaries have an unseen object with masses greater than 3 solar masses. c. Some X-ray binaries em ...
... 17. What observational evidence do we have that stellar death black holes really exist? a. Hollowed-out green spheres are sucking up matter in star forming regions and emitting gamma rays. b. Some X-ray binaries have an unseen object with masses greater than 3 solar masses. c. Some X-ray binaries em ...
Symposium on Telescope Science - Society for Astronomical Sciences
... This volume contains the proceedings of the 21st Conference of the IAPPP-Western Wing, Inc., which was held May 22 and 23, 2002 at the Northwoods Resort in the city of Big Bear Lake, California. The title chosen to set the theme of this year’s meeting was the Symposium on Telescope Science and much ...
... This volume contains the proceedings of the 21st Conference of the IAPPP-Western Wing, Inc., which was held May 22 and 23, 2002 at the Northwoods Resort in the city of Big Bear Lake, California. The title chosen to set the theme of this year’s meeting was the Symposium on Telescope Science and much ...
Astrophysics - Part 2
... Stefan’s law and Wien’s displacement law.General shape of black body curves, experimental verification is not required. Use of Wien’s displacement law to estimate black-body temperature of sources λmaxT = constant = 2.9 × 10-3 mK. Inverse square law, assumptions in its application. Use of Stefan’s l ...
... Stefan’s law and Wien’s displacement law.General shape of black body curves, experimental verification is not required. Use of Wien’s displacement law to estimate black-body temperature of sources λmaxT = constant = 2.9 × 10-3 mK. Inverse square law, assumptions in its application. Use of Stefan’s l ...
Document
... supernova was brighter than Venus for weeks before fading from view after nearly two years. •Even today, the nebula • is still expanding at • more than 3 million •miles per hour. ...
... supernova was brighter than Venus for weeks before fading from view after nearly two years. •Even today, the nebula • is still expanding at • more than 3 million •miles per hour. ...
An extrasolar planetary system with three
... algorithm yields orbital parameters that are indistinguishable from those we have found with the simple least-squares minimization, and confirms that the three-planet solution gives a superior fit compared to the two-planet model. Finally, we checked that the radial velocity variations are not partl ...
... algorithm yields orbital parameters that are indistinguishable from those we have found with the simple least-squares minimization, and confirms that the three-planet solution gives a superior fit compared to the two-planet model. Finally, we checked that the radial velocity variations are not partl ...
Observing Stellar Evolution
... star. Any element heavier (in the atomic sense) than helium is called a 'metal', even though this does not match our day-to-day use of the word. Kelvin (temperature) – This temperature scale is based on an absolute zero temperature – the temperature at which all molecular activity stops. Kelvin temp ...
... star. Any element heavier (in the atomic sense) than helium is called a 'metal', even though this does not match our day-to-day use of the word. Kelvin (temperature) – This temperature scale is based on an absolute zero temperature – the temperature at which all molecular activity stops. Kelvin temp ...
Direct Imaging and Spectroscopy of a Candidate Companion Below
... Sensitive optical to (sub)millimeter data reveal no clear evidence for circumstellar gas or dust (e.g. Cieza et al. 2007; Andrews and Williams 2007). We initially identified a candidate 3rd member of the ROXs 42B system located at a projected separation of ≈ 1.′′ 16 as a part of a general search for ...
... Sensitive optical to (sub)millimeter data reveal no clear evidence for circumstellar gas or dust (e.g. Cieza et al. 2007; Andrews and Williams 2007). We initially identified a candidate 3rd member of the ROXs 42B system located at a projected separation of ≈ 1.′′ 16 as a part of a general search for ...
Radial Velocity - Yale Exoplanet
... achieved the unprecedented precision of 15 m s−1 . Unfortunately, because of the small sample size, no planets were found. However, upper limits were set on M sin i for orbital periods out to 15 years for the 21 stars that they observed (Walker et al. 1995). Cross-correlation speedometers were also ...
... achieved the unprecedented precision of 15 m s−1 . Unfortunately, because of the small sample size, no planets were found. However, upper limits were set on M sin i for orbital periods out to 15 years for the 21 stars that they observed (Walker et al. 1995). Cross-correlation speedometers were also ...
ph600-12 - University of Kent
... of issues to be investigated. This project will focus on a specific phenomenom of high interest and motivation, in one of extragalactic astronomy, galactic astronomy, or solar system astronomy. The study will begin with a review of recent publications which address the issue and an evaluation of pos ...
... of issues to be investigated. This project will focus on a specific phenomenom of high interest and motivation, in one of extragalactic astronomy, galactic astronomy, or solar system astronomy. The study will begin with a review of recent publications which address the issue and an evaluation of pos ...
Astronomy Astrophysics NGC 7419 as a template for red supergiant clusters &
... 2007; Clark et al. 2009a). These clusters are so heavily obscured that their population of intrinsically blue stars have not been found yet, and only the RSGs have been observed as bright sources in the near-infrared. Population synthesis models indicate that, given the rarity of RSGs, the clusters ...
... 2007; Clark et al. 2009a). These clusters are so heavily obscured that their population of intrinsically blue stars have not been found yet, and only the RSGs have been observed as bright sources in the near-infrared. Population synthesis models indicate that, given the rarity of RSGs, the clusters ...
Hipparcos
Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky. This permitted the accurate determination of proper motions and parallaxes of stars, allowing a determination of their distance and tangential velocity. When combined with radial-velocity measurements from spectroscopy, this pinpointed all six quantities needed to determine the motion of stars. The resulting Hipparcos Catalogue, a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision Tycho Catalogue of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. Hipparcos ' follow-up mission, Gaia, was launched in 2013.The word ""Hipparcos"" is an acronym for High precision parallax collecting satellite and also a reference to the ancient Greek astronomer Hipparchus of Nicaea, who is noted for applications of trigonometry to astronomy and his discovery of the precession of the equinoxes.