Small Wonders: Andromeda
... debate (are there many galaxies or just one?) , and determining interstellar distances by the use of Cepheid variables. At the turn of the century, astronomers questions if the spiral nebula like M31 were ...
... debate (are there many galaxies or just one?) , and determining interstellar distances by the use of Cepheid variables. At the turn of the century, astronomers questions if the spiral nebula like M31 were ...
PDF file - Memorie della SAIt
... a fossil record of the nucleosynthesis that occurred several Gyr ago in halo AGB stars. They are dwarfs or giants, whose surface composition was polluted by the wind of an AGB companion. Then, the C and s-element enhancements are ashes of the nucleosynthesis occurred in the He-rich inter-shell of a ...
... a fossil record of the nucleosynthesis that occurred several Gyr ago in halo AGB stars. They are dwarfs or giants, whose surface composition was polluted by the wind of an AGB companion. Then, the C and s-element enhancements are ashes of the nucleosynthesis occurred in the He-rich inter-shell of a ...
How common are habitable planets?
... that only a small fraction of planets are oriented so that they cross in front of their host star as seen Provided by University of California - Berkeley from Earth, allowed them to estimate that 22 percent of all sun-like stars in the galaxy have Earthsize planets in their habitable zones. "The pri ...
... that only a small fraction of planets are oriented so that they cross in front of their host star as seen Provided by University of California - Berkeley from Earth, allowed them to estimate that 22 percent of all sun-like stars in the galaxy have Earthsize planets in their habitable zones. "The pri ...
Question Paper - SAVE MY EXAMS!
... Two stars have the same surface temperature but different sizes. Star X has twice the diameter of star Y. Which of the following statements is correct? A Star X has twice the luminosity of star Y. B Star X has four times the luminosity of star Y. C Star X has eight times the luminosity of star Y. D ...
... Two stars have the same surface temperature but different sizes. Star X has twice the diameter of star Y. Which of the following statements is correct? A Star X has twice the luminosity of star Y. B Star X has four times the luminosity of star Y. C Star X has eight times the luminosity of star Y. D ...
color magnitude diagrams - AST 114, Astronomy Lab II for Spring
... As you can see in Figure 1 above, if you take a random part of the sky (this is a sample of stars from the region around the constellation Orion), the stars form very distinct regions. An H-R diagram is essentially a graph of stars with each star’s location determined by their brightness or luminosi ...
... As you can see in Figure 1 above, if you take a random part of the sky (this is a sample of stars from the region around the constellation Orion), the stars form very distinct regions. An H-R diagram is essentially a graph of stars with each star’s location determined by their brightness or luminosi ...
September 2011 - Newbury Astronomical Society
... really does have the wow! factor for almost everyone who has the chance to look at it through an astronomical telescope. With the sky being light until around 22:30 and around midsummer the night sky not getting completely dark at all, some astronomers took to daylight observing. By fitting a specia ...
... really does have the wow! factor for almost everyone who has the chance to look at it through an astronomical telescope. With the sky being light until around 22:30 and around midsummer the night sky not getting completely dark at all, some astronomers took to daylight observing. By fitting a specia ...
The Celestial Sphere
... It is tilted 23.5° from it. The Sun’s path is called the Ecliptic It crosses the Celestial Equator twice: On about September 22nd,the Autumnal or Fall ...
... It is tilted 23.5° from it. The Sun’s path is called the Ecliptic It crosses the Celestial Equator twice: On about September 22nd,the Autumnal or Fall ...
SEEING STARS! SEEING STARS!
... Stars would not twinkle if we looked at them from outer space! They twinkle because we look at them through the Earth’s atmosphere which contains lots of pockets of warm and cold air. This bends the light (refraction) and so the stars twinkle. There is no air in outer space to bend the light. A blac ...
... Stars would not twinkle if we looked at them from outer space! They twinkle because we look at them through the Earth’s atmosphere which contains lots of pockets of warm and cold air. This bends the light (refraction) and so the stars twinkle. There is no air in outer space to bend the light. A blac ...
1998 - Universitäts-Sternwarte München
... (1975) atmosphere program that makes use of the standard assumptions such as hydrostatic equilibrium, plane-parallel layers and local thermodynamic equilibrium, and is fed by the opacity distribution functions described in Kurucz (1992) for an inclusion of the effects of line blanketing. The underly ...
... (1975) atmosphere program that makes use of the standard assumptions such as hydrostatic equilibrium, plane-parallel layers and local thermodynamic equilibrium, and is fed by the opacity distribution functions described in Kurucz (1992) for an inclusion of the effects of line blanketing. The underly ...
The View From Earth
... 1. Earth: (1) rotates on an axis once every 24 hours; (2) revolves about the Sun with period 365.25 days; (3) accompanies the Sun (and other planets) as it moves relative to other stars in its immediate neighborhood; (4) orbits about the center of the Milky Way galaxy, with period 230 million years; ...
... 1. Earth: (1) rotates on an axis once every 24 hours; (2) revolves about the Sun with period 365.25 days; (3) accompanies the Sun (and other planets) as it moves relative to other stars in its immediate neighborhood; (4) orbits about the center of the Milky Way galaxy, with period 230 million years; ...
Slide 1
... Crab pulsar is slowing down at a rate that is consistent with an age of about 1000 years (plus light travel time), which is when the supernova was observed. The sharpness of the pulses indicates that they come from a region roughly 100 km across, since otherwise the finite travel time for light to m ...
... Crab pulsar is slowing down at a rate that is consistent with an age of about 1000 years (plus light travel time), which is when the supernova was observed. The sharpness of the pulses indicates that they come from a region roughly 100 km across, since otherwise the finite travel time for light to m ...
Events: - Temecula Valley Astronomers
... a few degrees. You will see two stars running up and down from each other. These are Delta on the bottom and Gamma on the top. If you look just to the right of these two stars, about half way between them, you will see a nice open cluster called M-44 or “Beehive Cluster”. M-44 is an easy find using ...
... a few degrees. You will see two stars running up and down from each other. These are Delta on the bottom and Gamma on the top. If you look just to the right of these two stars, about half way between them, you will see a nice open cluster called M-44 or “Beehive Cluster”. M-44 is an easy find using ...
July 2014 BRAS Newsletter - The Baton Rouge Astronomical Society
... However, extrapolation from Kepler data of star systems with shorter-period orbits strongly suggests that nearly 6 percent of Sun-like stars have an Earth-size planet in an Earth-like orbit of 200 to 400 days. “Naturally, such an extrapolation carries less weight than a direct measurement,” the auth ...
... However, extrapolation from Kepler data of star systems with shorter-period orbits strongly suggests that nearly 6 percent of Sun-like stars have an Earth-size planet in an Earth-like orbit of 200 to 400 days. “Naturally, such an extrapolation carries less weight than a direct measurement,” the auth ...
On the Permissible Numerical Value of the
... any light beam arrives back at its initial point after travelling across the whole space. So light beams emitted into such a space from the opposite (invisible to us) side of the Sun should travel across the space then also meet the Earth, then create an anti-image of the Sun from the opposite side ...
... any light beam arrives back at its initial point after travelling across the whole space. So light beams emitted into such a space from the opposite (invisible to us) side of the Sun should travel across the space then also meet the Earth, then create an anti-image of the Sun from the opposite side ...
Today: Magnitude Terminology Photometry Applications Reading
... a star calibrated relative to the known flux standard (e.g. Vega); typically obtained by calculating differential magnitude w.r.t. a known standard star. ...
... a star calibrated relative to the known flux standard (e.g. Vega); typically obtained by calculating differential magnitude w.r.t. a known standard star. ...
Lecture 6-1: Schematic Evolution of Stars as seen from the core
... increase to support the star against gravity. As thermal pressure scales with r while hydrostatic pressure scales with r4/3, a more massive star requires a higher central temperature (and/or lower density). For a non-relativistic degenerate gas, temperature doesn’t enter. Now, thermal pressure scale ...
... increase to support the star against gravity. As thermal pressure scales with r while hydrostatic pressure scales with r4/3, a more massive star requires a higher central temperature (and/or lower density). For a non-relativistic degenerate gas, temperature doesn’t enter. Now, thermal pressure scale ...
The Milky Way Galaxy
... Radar ranging - good for measuring distances in the solar system (up to about 0.0001 light years) Parallax - good for measuring distances to a few hundred light years ...
... Radar ranging - good for measuring distances in the solar system (up to about 0.0001 light years) Parallax - good for measuring distances to a few hundred light years ...
File
... • As temperature in the star increases with depth, the ash of each burning stage becomes fuel for the next stage. • The inner core of the star is made of iron, which is surrounded by shells of silicon, ...
... • As temperature in the star increases with depth, the ash of each burning stage becomes fuel for the next stage. • The inner core of the star is made of iron, which is surrounded by shells of silicon, ...
Origin of stars
... “Stars are formed by the gravitational collapse of cool dense gas and dust clouds…. There are problems, however, in initiating the collapse of a gas cloud. It resists collapse because of firstly its internal motions and the heating effects of nearby stars, secondly the centrifugal support due to rot ...
... “Stars are formed by the gravitational collapse of cool dense gas and dust clouds…. There are problems, however, in initiating the collapse of a gas cloud. It resists collapse because of firstly its internal motions and the heating effects of nearby stars, secondly the centrifugal support due to rot ...
Age-Dating of Young Stars and Stellar Systems
... between atmosphere and evolution models during the W-R phase. If non-thermal heating is not negligible, for instance when strong stellar winds and supernovae are present (cf. Section 3.4), the emission-line spectrum may become affected by shocked gas. Viegas et al. (1999) suggested that some line ra ...
... between atmosphere and evolution models during the W-R phase. If non-thermal heating is not negligible, for instance when strong stellar winds and supernovae are present (cf. Section 3.4), the emission-line spectrum may become affected by shocked gas. Viegas et al. (1999) suggested that some line ra ...
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.