A re-appraisal of the habitability of planets around M dwarf
... which are designated as lowercase m, and absolute magnitudes, which are designated as uppercase M and defined as the apparent magnitude that a star would have if it were at a distance of 10 pc (!33 light years) from the observer. Observations were historically made with the naked eye, then eyes with ...
... which are designated as lowercase m, and absolute magnitudes, which are designated as uppercase M and defined as the apparent magnitude that a star would have if it were at a distance of 10 pc (!33 light years) from the observer. Observations were historically made with the naked eye, then eyes with ...
A Reappraisal of The Habitability of Planets around M Dwarf Stars
... which are designated as lowercase m, and absolute magnitudes, which are designated as uppercase M and defined as the apparent magnitude that a star would have if it were at a distance of 10 pc (33 light years) from the observer. Observations were historically made with the naked eye, then eyes with ...
... which are designated as lowercase m, and absolute magnitudes, which are designated as uppercase M and defined as the apparent magnitude that a star would have if it were at a distance of 10 pc (33 light years) from the observer. Observations were historically made with the naked eye, then eyes with ...
Discovery of extremely lead-rich subdwarfs: does heavy metal signal
... since they behave as helium main-sequence or extended horizontalbranch stars of approximately half a solar mass (Heber 2009). The puzzle is that the majority are believed to be red giant cores, stripped of their hydrogen envelopes, so at best their outer layers should be enriched in helium. Whilst t ...
... since they behave as helium main-sequence or extended horizontalbranch stars of approximately half a solar mass (Heber 2009). The puzzle is that the majority are believed to be red giant cores, stripped of their hydrogen envelopes, so at best their outer layers should be enriched in helium. Whilst t ...
Test 3 Review Clicker Questions
... a) cannot explain how the Sun is stable. b) detect only one-third the number of neutrinos expected by theory. c) cannot detect neutrinos easily. d) are unable to explain how neutrinos oscillate between other types. e) cannot create controlled fusion ...
... a) cannot explain how the Sun is stable. b) detect only one-third the number of neutrinos expected by theory. c) cannot detect neutrinos easily. d) are unable to explain how neutrinos oscillate between other types. e) cannot create controlled fusion ...
Homework #3, AST 1002
... Which of the following is (are) correct? (a) Energy is transported from the Sun's core to its surface primarily by a process called convection. (b) It takes about five minutes for energy from the Sun's core to reach its surface. (c) The proton cycle describes the process of energy production in the ...
... Which of the following is (are) correct? (a) Energy is transported from the Sun's core to its surface primarily by a process called convection. (b) It takes about five minutes for energy from the Sun's core to reach its surface. (c) The proton cycle describes the process of energy production in the ...
Neon abundances - UCL Astrophysics Group
... from marginal deficits of 0.1±0.3 dex to underabundances of an order of magnitude or more. In many cases, the lines are so weak that only upper limits can be established. The most extreme example found is y Her with an underabundance of at least 1.5 dex. These underabundances are qualitatively expec ...
... from marginal deficits of 0.1±0.3 dex to underabundances of an order of magnitude or more. In many cases, the lines are so weak that only upper limits can be established. The most extreme example found is y Her with an underabundance of at least 1.5 dex. These underabundances are qualitatively expec ...
Astronomy 250 - University of Victoria
... Of course, the stars have motions of their own, and do not remain fixed in the sky. That these stars do move perceptibly was first noticed in 1718 by Edmund Halley. He found the positions of Aldebaran, Sirius, and Arcturus to be half a degree different from those cataloged by Ptolemy, Hipparchus and ...
... Of course, the stars have motions of their own, and do not remain fixed in the sky. That these stars do move perceptibly was first noticed in 1718 by Edmund Halley. He found the positions of Aldebaran, Sirius, and Arcturus to be half a degree different from those cataloged by Ptolemy, Hipparchus and ...
Multi-Wavelength Observations of Known, and Searches
... - Continue to perform periodicity searches on all cataloged sources, hoping to fnd more binaries. - Use 2nd Fermi catalog (2FGL) which contains 1,873 sources, and better source characterization than 1FGL catalog. – Accurate source parameters are required to calculate photon probabilities for source ...
... - Continue to perform periodicity searches on all cataloged sources, hoping to fnd more binaries. - Use 2nd Fermi catalog (2FGL) which contains 1,873 sources, and better source characterization than 1FGL catalog. – Accurate source parameters are required to calculate photon probabilities for source ...
CHAPTER 1 The Formation and Structure of Stars
... • How do astronomers know there is an interstellar medium, and how do they know its properties? – In some cases, the interstellar medium is easily visible as clouds of gas and dust—as in the case of the Great Nebula in Orion. – Astronomers call such a cloud a nebula—from the Latin word for cloud. – ...
... • How do astronomers know there is an interstellar medium, and how do they know its properties? – In some cases, the interstellar medium is easily visible as clouds of gas and dust—as in the case of the Great Nebula in Orion. – Astronomers call such a cloud a nebula—from the Latin word for cloud. – ...
PDF
... BUT: requires 3000 times normal halo DM density in GCs and very optimistic capture rate. If true, then only one small window left below MACHO/EROS microlensing limits ...
... BUT: requires 3000 times normal halo DM density in GCs and very optimistic capture rate. If true, then only one small window left below MACHO/EROS microlensing limits ...
don_lamb - New Views of the Universe
... accretion disk) Explains long GRBs Dominant timescale is set by jet propagation through collapsing core (~10-20 s) ...
... accretion disk) Explains long GRBs Dominant timescale is set by jet propagation through collapsing core (~10-20 s) ...
The first carbon-enhanced metal-poor star found in the Sculptor
... patterns that suggest mass transfer from a companion in the AGB phase (Lucatello et al. 2005). Thus the C, N, O, and heavy elements for these stars do not reflect the ISM from which they were formed. The available data for CEMP-s stars is consistent with ∼100% binary fraction and a maximum period of ...
... patterns that suggest mass transfer from a companion in the AGB phase (Lucatello et al. 2005). Thus the C, N, O, and heavy elements for these stars do not reflect the ISM from which they were formed. The available data for CEMP-s stars is consistent with ∼100% binary fraction and a maximum period of ...
Here
... Conclusion: It is not possible to reproduce the observed distribution if all galaxies are either prolate or oblate axisymmetrical ellipsoids. ...
... Conclusion: It is not possible to reproduce the observed distribution if all galaxies are either prolate or oblate axisymmetrical ellipsoids. ...
PDF Full-text
... lines and continua all increase in brightness with increasing magnetic heating in solar active regions. In the semiempirical non-LTE (local thermodynamic equilibrium) models of the solar chromosphere, transition region, and corona computed by Fontenla et al. [29,30], this increase in brightness resu ...
... lines and continua all increase in brightness with increasing magnetic heating in solar active regions. In the semiempirical non-LTE (local thermodynamic equilibrium) models of the solar chromosphere, transition region, and corona computed by Fontenla et al. [29,30], this increase in brightness resu ...
Interacting Galaxies
... While galaxies collide, with very rare exceptions, the stars within them do not. This is because so much of a galaxy is simply empty space, with distances between stars about 100 million times larger than their stellar diameters. What collides is the gas and dust between the stars, which produces a ...
... While galaxies collide, with very rare exceptions, the stars within them do not. This is because so much of a galaxy is simply empty space, with distances between stars about 100 million times larger than their stellar diameters. What collides is the gas and dust between the stars, which produces a ...
The extreme ultraviolet and X-ray Sun in Time: High
... on the MS, giving observational constraints on the percentiles at these ages (with 230, 134, and 36 stars, respectively at the considered ages). We use additional constraints for pre-mainsequence (PMS) rotation from the ≈2 Myr cluster NGC 6530 (28 stars; Henderson & Stassun 2012) and the ≈12 Myr clu ...
... on the MS, giving observational constraints on the percentiles at these ages (with 230, 134, and 36 stars, respectively at the considered ages). We use additional constraints for pre-mainsequence (PMS) rotation from the ≈2 Myr cluster NGC 6530 (28 stars; Henderson & Stassun 2012) and the ≈12 Myr clu ...
offprint
... similar to β Cephei stars (Ledoux 1951), where the lpv would result from non-radial pulsation (nrp) in a single g-mode with harmonic degree = 2 and azimuthal order m = +2. Balona et al. (1999) did not succeed in reproducing the lpv of He 6678 assuming nrp, while an (ad-hoc) model based on variab ...
... similar to β Cephei stars (Ledoux 1951), where the lpv would result from non-radial pulsation (nrp) in a single g-mode with harmonic degree = 2 and azimuthal order m = +2. Balona et al. (1999) did not succeed in reproducing the lpv of He 6678 assuming nrp, while an (ad-hoc) model based on variab ...
19_Testbank - Lick Observatory
... 9) Almost all elements heavier than hydrogen and helium were made inside stars. Answer: TRUE 10) Most of the current star formation in the Milky Way occurs in spiral arms. Answer: TRUE 19.3 Short Answer Questions 1) Suppose you discovered a star made purely of hydrogen and helium. How old do you th ...
... 9) Almost all elements heavier than hydrogen and helium were made inside stars. Answer: TRUE 10) Most of the current star formation in the Milky Way occurs in spiral arms. Answer: TRUE 19.3 Short Answer Questions 1) Suppose you discovered a star made purely of hydrogen and helium. How old do you th ...
Automated Detection and Analysis of Meteor Events Using Nightly
... When the stars on my image have been matched to known stars, the magnitudes of the known stars are used to calibrate the event. If more than one known star is found near the image star the closest known star to the image star was used. After I know that stars have a match I run APER on the images st ...
... When the stars on my image have been matched to known stars, the magnitudes of the known stars are used to calibrate the event. If more than one known star is found near the image star the closest known star to the image star was used. After I know that stars have a match I run APER on the images st ...
Rotation Periods of Wide Binaries in the Kepler Field
... field of the Kepler spacecraft I identified 93 likely binary systems. A comparison of their rotation periods is a test of the gyrochronology concept. To find their periods I calculated the autocorrelation function of the Kepler mission photometry for each star. In most systems for which good periods ...
... field of the Kepler spacecraft I identified 93 likely binary systems. A comparison of their rotation periods is a test of the gyrochronology concept. To find their periods I calculated the autocorrelation function of the Kepler mission photometry for each star. In most systems for which good periods ...
Betelgeuse - TeacherWeb
... • In 1995 the Hubble’s telescope discovered Betelgeuse. It has been noticed before but never named. In 1836 Sir John Frederick William Hersche noticed that Betelgeuse had changed in brightness. ...
... • In 1995 the Hubble’s telescope discovered Betelgeuse. It has been noticed before but never named. In 1836 Sir John Frederick William Hersche noticed that Betelgeuse had changed in brightness. ...
Lyra
Lyra (/ˈlaɪərə/; Latin for lyre, from Greek λύρα) is a small constellation. It is one of 48 listed by the 2nd century astronomer Ptolemy, and is one of the 88 constellations recognized by the International Astronomical Union. Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, and hence sometimes referred to as Aquila Cadens or Vultur Cadens. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus. Lyra is visible from the northern hemisphere from spring through autumn, and nearly overhead, in temperate latitudes, during the summer months. From the southern hemisphere, it is visible low in the northern sky during the winter months.The lucida or brightest star—and one of the brightest stars in the sky—is the white main sequence star Vega, a corner of the Summer Triangle. Beta Lyrae is the prototype of a class of stars known as Beta Lyrae variables, binary stars so close to each other that they become egg-shaped and material flows from one to the other. Epsilon Lyrae, known informally as the Double Double, is a complex multiple star system. Lyra also hosts the Ring Nebula, the second-discovered and best-known planetary nebula.