Prospecting for Planets – Radial Velocity Searches
... The first planet orbiting a star other than our Sun (or 'exoplanet') was discovered in 1992, orbiting an odd type of star known as a pulsar. It wasn't until three years later that the next exoplanet was discovered, this time around a star similar to our Sun. Since then the number of exoplanets we ha ...
... The first planet orbiting a star other than our Sun (or 'exoplanet') was discovered in 1992, orbiting an odd type of star known as a pulsar. It wasn't until three years later that the next exoplanet was discovered, this time around a star similar to our Sun. Since then the number of exoplanets we ha ...
Analysis of Two Pulsating X-ray Sources
... Calculations and Interpretations: The acceleration due to gravity (g) on the surface of a star (according to Newton’s Universal Law of Gravitation) is given by g = (GM)/R2 where G = 6.67 X 10-11 Nm2/kg2, M=star’s mass and R = star’s radius Centripetal acceleration (ac) of an object on the surface o ...
... Calculations and Interpretations: The acceleration due to gravity (g) on the surface of a star (according to Newton’s Universal Law of Gravitation) is given by g = (GM)/R2 where G = 6.67 X 10-11 Nm2/kg2, M=star’s mass and R = star’s radius Centripetal acceleration (ac) of an object on the surface o ...
Exoplanets - Mid-Pacific Institute
... systems may be due to limitations of current methods and technologies Planets smaller than gas giants cannot be reliably detected ...
... systems may be due to limitations of current methods and technologies Planets smaller than gas giants cannot be reliably detected ...
File - Mr. Catt`s Class
... The Chandrasekhar Limit 1. Even though electron degeneracy supports the white dwarf against collapsing completely, there is a limit to the amount of pressure degenerate electrons can withstand. 2. This limit to the mass of a white dwarf above which it cannot be supported by electron degeneracy and ...
... The Chandrasekhar Limit 1. Even though electron degeneracy supports the white dwarf against collapsing completely, there is a limit to the amount of pressure degenerate electrons can withstand. 2. This limit to the mass of a white dwarf above which it cannot be supported by electron degeneracy and ...
THE CHANGING SKY
... throughout a day (or night). The most familiar example of this motion is day and night. The Sun rises in the east when the Earth rotates us around so that the Sun is shining down on us. It sets in the west every day because we have rotated with the Earth so that we are in the shadow of the Earth on ...
... throughout a day (or night). The most familiar example of this motion is day and night. The Sun rises in the east when the Earth rotates us around so that the Sun is shining down on us. It sets in the west every day because we have rotated with the Earth so that we are in the shadow of the Earth on ...
OSP2016Level 3 Map - Oregon Star Party
... What is it? V404 Cyg is a black hole (12+/- 3 solar masses) with late K or early G type stellar companion that’s slightly smaller than the Sun, orbiting each other in less than 6.5 days. They are approximately 7800 light years away. Why you want to see it: The stellar companion is distorted into a ...
... What is it? V404 Cyg is a black hole (12+/- 3 solar masses) with late K or early G type stellar companion that’s slightly smaller than the Sun, orbiting each other in less than 6.5 days. They are approximately 7800 light years away. Why you want to see it: The stellar companion is distorted into a ...
Spectra of Star Clusters
... • What is luminosity and how do we determine it? • A star’s luminosity is the total power (energy per unit time) that it radiates into space. It can be calculated from a star’s measured apparent brightness and distance, using the luminosity‐distance formula: apparent brightness = luminosity / (4 ...
... • What is luminosity and how do we determine it? • A star’s luminosity is the total power (energy per unit time) that it radiates into space. It can be calculated from a star’s measured apparent brightness and distance, using the luminosity‐distance formula: apparent brightness = luminosity / (4 ...
THE HR DIAGRAM
... Late in the nineteenth century, astronomers had tools that revealed a great deal about stars. By that time, advances in telescope design and photographic emulsions were becoming mature. They were able to take spectral images of stars which revealed their composition and th ...
... Late in the nineteenth century, astronomers had tools that revealed a great deal about stars. By that time, advances in telescope design and photographic emulsions were becoming mature. They were able to take spectral images of stars which revealed their composition and th ...
The Application of Forbidden Line X-Ray Diagnostics to the Hot Star
... indicates the strength of the UV field.* In a strong UV field, electrons are often excited out of the long-lived upper level of the forbidden line before they spontaneously de-excite, weakening the forbidden line. * If electron densities are high enough, collisional excitation will destroy the forbi ...
... indicates the strength of the UV field.* In a strong UV field, electrons are often excited out of the long-lived upper level of the forbidden line before they spontaneously de-excite, weakening the forbidden line. * If electron densities are high enough, collisional excitation will destroy the forbi ...
What units are used in astronomical photometry?
... Astrometry: Technological advances (including the Hubble Space Telescope) have improved parallax accuracy to 0.001” within a few years. Before 1990, fewer than 10,000 stellar parallaxes had been measured (and only 500 known well), but there are about 10 12 stars in our Galaxy. Space observations mad ...
... Astrometry: Technological advances (including the Hubble Space Telescope) have improved parallax accuracy to 0.001” within a few years. Before 1990, fewer than 10,000 stellar parallaxes had been measured (and only 500 known well), but there are about 10 12 stars in our Galaxy. Space observations mad ...
Variable star information
... Classical Cepheid variables are highly luminous, yellow giant or supergiant stars that pulsate on a very regular basis. Some of them change in brightness very quickly, over a period of only one day, whereas others are characterised by slower changes and have periods of up to 70 days. Their masses ra ...
... Classical Cepheid variables are highly luminous, yellow giant or supergiant stars that pulsate on a very regular basis. Some of them change in brightness very quickly, over a period of only one day, whereas others are characterised by slower changes and have periods of up to 70 days. Their masses ra ...
File
... Such a star is called a red giant. Red giants appear at the upper right of temperature-luminosity (Hertzsprung-Russell) diagrams. The Sun will be in this stage, or on the way to it after the main sequence, for about a billion years, only 10 per cent of its lifetime on the main sequence. Red giants a ...
... Such a star is called a red giant. Red giants appear at the upper right of temperature-luminosity (Hertzsprung-Russell) diagrams. The Sun will be in this stage, or on the way to it after the main sequence, for about a billion years, only 10 per cent of its lifetime on the main sequence. Red giants a ...
Planetarium Key Points
... Using a motionless sphere we can define a great circle, the horizon, and its poles, zenit and nadir 2. The daily motion of the sphere From Est to West around an axis that seems fixed on the sphere (for short periods of time) The motion and the sphere define two poles and an equator, we can use ...
... Using a motionless sphere we can define a great circle, the horizon, and its poles, zenit and nadir 2. The daily motion of the sphere From Est to West around an axis that seems fixed on the sphere (for short periods of time) The motion and the sphere define two poles and an equator, we can use ...
MS Word version
... Question 1: Complete the following table involving the horizon coordinate system. You should predict the answers and then use the simulator to check them. Remember that you can measure coordinates by dragging the active star to that location. ...
... Question 1: Complete the following table involving the horizon coordinate system. You should predict the answers and then use the simulator to check them. Remember that you can measure coordinates by dragging the active star to that location. ...
Problems in Chapter 13
... strongly at about 500 nm. What is its temperature? How does this compare to the Sun. . Alpha Centauri has its peak radiation at 500 nm. Applying Wien’s Law, T = 3 × 106 K nm / 500 nm = 6000 K. The temperature of this star is approximately the same as our Sun’s, so Alpha Centauri has a similar spectr ...
... strongly at about 500 nm. What is its temperature? How does this compare to the Sun. . Alpha Centauri has its peak radiation at 500 nm. Applying Wien’s Law, T = 3 × 106 K nm / 500 nm = 6000 K. The temperature of this star is approximately the same as our Sun’s, so Alpha Centauri has a similar spectr ...
Structure of the Universe
... massive stars, but rather a white dwarf that accretes mass from a companion until it exceeds the Chandrasekhar limit (1.4 Msun) ...
... massive stars, but rather a white dwarf that accretes mass from a companion until it exceeds the Chandrasekhar limit (1.4 Msun) ...
Night Sky Course Stars and Star Clusters within the
... about 15 light years. The cluster is only about 500 light years away – farther than the Pleiades. The bright orange stars are the ones that have had time to evolve into red giants. (Given the estimates of mass for those stars still remaining on the main sequence, we can use our models of stellar evo ...
... about 15 light years. The cluster is only about 500 light years away – farther than the Pleiades. The bright orange stars are the ones that have had time to evolve into red giants. (Given the estimates of mass for those stars still remaining on the main sequence, we can use our models of stellar evo ...
Perseus (constellation)
Perseus, named after the Greek mythological hero Perseus, is a constellation in the northern sky. It was one of 48 listed by the 2nd-century astronomer Ptolemy and among the 88 modern constellations defined by the International Astronomical Union (IAU). It is located in the northern celestial hemisphere near several other constellations named after legends surrounding Perseus, including Andromeda to the west and Cassiopeia to the north. Perseus is also bordered by Aries and Taurus to the south, Auriga to the east, Camelopardalis to the north, and Triangulum to the west.The galactic plane of the Milky Way passes through Perseus but is mostly obscured by molecular clouds. The constellation's brightest star is the yellow-white supergiant Alpha Persei (also called Mirfak), which shines at magnitude 1.79. It and many of the surrounding stars are members of an open cluster known as the Alpha Persei Cluster. The best-known star, however, is Algol (Beta Persei), linked with ominous legends because of its variability, which is noticeable to the naked eye. Rather than being an intrinsically variable star, it is an eclipsing binary. Other notable star systems in Perseus include X Persei, a binary system containing a neutron star, and GK Persei, a nova that peaked at magnitude 0.2 in 1901. The Double Cluster, comprising two open clusters quite near each other in the sky, was known to the ancient Chinese. The constellation gives its name to the Perseus Cluster (Abell 426), a massive galaxy cluster located 250 million light-years from Earth. It hosts the radiant of the annual Perseids meteor shower—one of the most prominent meteor showers in the sky.