A young massive planet in a star-disk system
... The orbital period is ‘close’ to the ones found in TW Hya Accretion events. TW Hya: Up to know variable periodicities (due to accretion) within years, not months… And the target is one of the oldest CTTS (accretion rate ~2 orders of magnitude smaller than younger CTTS) ...
... The orbital period is ‘close’ to the ones found in TW Hya Accretion events. TW Hya: Up to know variable periodicities (due to accretion) within years, not months… And the target is one of the oldest CTTS (accretion rate ~2 orders of magnitude smaller than younger CTTS) ...
Introduction: The History and Technique of Stellar Classification
... Introduction: The History and Technique of Stellar Classification Patterns of absorption lines were first observed in the spectrum of the sun by the German physicist Joseph von Fraunhofer early in the 1800’s, but it was not until late in that century that astronomers were able to routinely examine t ...
... Introduction: The History and Technique of Stellar Classification Patterns of absorption lines were first observed in the spectrum of the sun by the German physicist Joseph von Fraunhofer early in the 1800’s, but it was not until late in that century that astronomers were able to routinely examine t ...
12 Introduction to Cepheid Variable Stars Exercise
... Cepheid variable stars are members of the pulsating variable class of variable stars. Cepheids are similar to RR Lyrae variable stars, but are relatively rare when compared to the population density of other types of variable stars. Recalling the discussion of apparent and absolute brightness of sta ...
... Cepheid variable stars are members of the pulsating variable class of variable stars. Cepheids are similar to RR Lyrae variable stars, but are relatively rare when compared to the population density of other types of variable stars. Recalling the discussion of apparent and absolute brightness of sta ...
December - Rose City Astronomers
... stroke of cosmic serendipity in an area nearly devoid of other major deep-sky objects. The refractor at 44x shows the 12' diameter star cluster as six stars (9th to 11thmagnitude) embedded in a background haze of a half dozen more fainter suns. The Triangulum or Pinwheel Galaxy, also known as M33 (N ...
... stroke of cosmic serendipity in an area nearly devoid of other major deep-sky objects. The refractor at 44x shows the 12' diameter star cluster as six stars (9th to 11thmagnitude) embedded in a background haze of a half dozen more fainter suns. The Triangulum or Pinwheel Galaxy, also known as M33 (N ...
Option D – Astrophysics
... Planets are objects of sufficient mass that gravitational forces have formed them into spherical shapes, but their mass is not large enough for nuclear fusion to occur. In other words, they are not massive enough to be stars. To distinguish planets from some smaller orbiting masses, it has been nece ...
... Planets are objects of sufficient mass that gravitational forces have formed them into spherical shapes, but their mass is not large enough for nuclear fusion to occur. In other words, they are not massive enough to be stars. To distinguish planets from some smaller orbiting masses, it has been nece ...
Kepler Mission
... partly caused by its closeness to Kepler 2 which has a photospheric temperature of 6350 Kelvin, a temperature greater than our own Sun. Kepler 2 is larger than the Sun (1.991 solar radii) and more massive (1.52 solar masses) too.3 After these first two observations of stellar systems within our Milk ...
... partly caused by its closeness to Kepler 2 which has a photospheric temperature of 6350 Kelvin, a temperature greater than our own Sun. Kepler 2 is larger than the Sun (1.991 solar radii) and more massive (1.52 solar masses) too.3 After these first two observations of stellar systems within our Milk ...
Small Wonders: Cygnus
... Three degrees almost directly east of Deneb, we come across one of the most photographed nebulae in the night sky. The North American Nebula is spectacular in long exposure photographs, and unlike many objects in the sky clearly resembles its namesake. Until recently tho, its been considered a chall ...
... Three degrees almost directly east of Deneb, we come across one of the most photographed nebulae in the night sky. The North American Nebula is spectacular in long exposure photographs, and unlike many objects in the sky clearly resembles its namesake. Until recently tho, its been considered a chall ...
Chemical composition of 90 F and G disk dwarfs
... evolution (GCE) in detail, some old conclusions have, however, been challenged and new questions have arisen. Particularly important is the detailed abundance analysis of 189 F and G dwarfs with −1.1 < [Fe/H] < 0.25 by Edvardsson et al. (1993a, hereafter EAGLNT). The main results from this work may ...
... evolution (GCE) in detail, some old conclusions have, however, been challenged and new questions have arisen. Particularly important is the detailed abundance analysis of 189 F and G dwarfs with −1.1 < [Fe/H] < 0.25 by Edvardsson et al. (1993a, hereafter EAGLNT). The main results from this work may ...
Ptolemy: on trial for fraud
... above all, that the Almagest is not like a modern research paper. It is a well-honed textbook, modelled as much as applicable on Euclid’s Elements. It was no doubt Ptolemy’s intention to present the procedures with sample data so that future astronomers could see how it was done and could introduce ...
... above all, that the Almagest is not like a modern research paper. It is a well-honed textbook, modelled as much as applicable on Euclid’s Elements. It was no doubt Ptolemy’s intention to present the procedures with sample data so that future astronomers could see how it was done and could introduce ...
Folie 1
... have to be detected before a measurable signal can be produced. A single X-ray photon can produce 100-1000 electrons (1 electron per 3.6 eV of energy). With low amplifier noise this can be measured. Thus X-ray CCDs are photon counting devices • Requires one photon incident per pixel which means inte ...
... have to be detected before a measurable signal can be produced. A single X-ray photon can produce 100-1000 electrons (1 electron per 3.6 eV of energy). With low amplifier noise this can be measured. Thus X-ray CCDs are photon counting devices • Requires one photon incident per pixel which means inte ...
The ages of pre-main-sequence stars
... the initial conditions can be determined and the underlying accretion rate has been constant in the past. Because of the balance established between the Kelvin±Helmholtz, contraction time-scale and the accretion time-scale, a pre-main-sequence star remembers its accretion history. Knowledge of the c ...
... the initial conditions can be determined and the underlying accretion rate has been constant in the past. Because of the balance established between the Kelvin±Helmholtz, contraction time-scale and the accretion time-scale, a pre-main-sequence star remembers its accretion history. Knowledge of the c ...
A History of Astronomy, Astrophysics and Cosmology
... The Earth was composed of the four elements of earth, air, fire and water, but there was a fifth pure element, the aether, which was the substance out of which the celestial bodies were made. This was the background against which the Ptolemaic geocentric system of the world was constructed. Accordin ...
... The Earth was composed of the four elements of earth, air, fire and water, but there was a fifth pure element, the aether, which was the substance out of which the celestial bodies were made. This was the background against which the Ptolemaic geocentric system of the world was constructed. Accordin ...
Planet Hunters Education Guide
... them particularly adept at identifying faces, objects, words and sounds. Computers are now sometimes being used to identify faces, but this extremely expensive technology still only works in ideal conditions and generally fails where lighting is poor or where faces are turned to the side. Images use ...
... them particularly adept at identifying faces, objects, words and sounds. Computers are now sometimes being used to identify faces, but this extremely expensive technology still only works in ideal conditions and generally fails where lighting is poor or where faces are turned to the side. Images use ...
11 The Interstellar Medium
... This H–R diagram shows the evolution of stars somewhat more and somewhat less massive than the Sun. The shape of the paths is similar, but they wind up in different places on the main sequence. ...
... This H–R diagram shows the evolution of stars somewhat more and somewhat less massive than the Sun. The shape of the paths is similar, but they wind up in different places on the main sequence. ...
Drawing Constellations
... immensely vain. She was also proud of her daughter's beauty. In fact she continually boasted that the two of them were more beautiful than any of the fifty sea nymphs who attended Poseidon's court. – These nymphs (the Nereids) complained to Poseidon, who felt he had to defend his own reputation. So ...
... immensely vain. She was also proud of her daughter's beauty. In fact she continually boasted that the two of them were more beautiful than any of the fifty sea nymphs who attended Poseidon's court. – These nymphs (the Nereids) complained to Poseidon, who felt he had to defend his own reputation. So ...
Can Extra Mixing in RGB and AGB Stars Be Attributed to Magnetic
... are determined by the transport rates needed by CBP for the model stellar structure of a star of initially 1.5 M⊙ , in both the AGB and RGB phases. The field required for the AGB star in the processing zone is B0 ∼ 5 × 106 G; at the base of the convective envelope this yields an intensity BE . 104 G ...
... are determined by the transport rates needed by CBP for the model stellar structure of a star of initially 1.5 M⊙ , in both the AGB and RGB phases. The field required for the AGB star in the processing zone is B0 ∼ 5 × 106 G; at the base of the convective envelope this yields an intensity BE . 104 G ...
PDF only - at www.arxiv.org.
... In 2015 the Associated Universities for Research in Astronomy (AURA) published a new vision for the 2030s entitled “From Cosmic Birth to Living Earths: The Future of UVOIR Space Astronomy”. The report caps a two-year AURA-chartered study of how the ambitious goals of exoplanet and cosmic origins sci ...
... In 2015 the Associated Universities for Research in Astronomy (AURA) published a new vision for the 2030s entitled “From Cosmic Birth to Living Earths: The Future of UVOIR Space Astronomy”. The report caps a two-year AURA-chartered study of how the ambitious goals of exoplanet and cosmic origins sci ...
1 Distance: A History of Parallax and Brief Introduction to Standard
... universe. The only person from antiquity to be truly impressed with his theory was Seleucus of Seleucia, either a Chaldean or Babylonian astronomer [Ferguson 28]. The changes in brightness of the planets could easily be accounted for in a heliocentric model. The distances between planets continuousl ...
... universe. The only person from antiquity to be truly impressed with his theory was Seleucus of Seleucia, either a Chaldean or Babylonian astronomer [Ferguson 28]. The changes in brightness of the planets could easily be accounted for in a heliocentric model. The distances between planets continuousl ...
Determination of accurate stellar radial
... observations were made 1997 in two separate runs on February 18–23 and October 15–23. The campaign targeted mainly stars in the Hyades and Ursa Major open clusters, but also included a set of IAU radial-velocity standards, some low-metallicity stars, Procyon and 51 Peg. Lunar spectra were also obtai ...
... observations were made 1997 in two separate runs on February 18–23 and October 15–23. The campaign targeted mainly stars in the Hyades and Ursa Major open clusters, but also included a set of IAU radial-velocity standards, some low-metallicity stars, Procyon and 51 Peg. Lunar spectra were also obtai ...
A Stargazers Guide to Astronomy
... All sciences are making an advance, but Astronomy is moving at high speed. Since the principles of this science were settled by Copernicus, four hundred years ago, it has never had to beat a retreat. It is rewritten not to correct material errors, but to incorporate new discoveries. At one time, Ast ...
... All sciences are making an advance, but Astronomy is moving at high speed. Since the principles of this science were settled by Copernicus, four hundred years ago, it has never had to beat a retreat. It is rewritten not to correct material errors, but to incorporate new discoveries. At one time, Ast ...
Institute for Astrophysical Research Seminar Series
... Mimir -- Our Near-Infared Imager, Spectrometer, and Polarimeter on the Perkins Telescope ...
... Mimir -- Our Near-Infared Imager, Spectrometer, and Polarimeter on the Perkins Telescope ...