The Milky Way - Midlandstech
... Comparing absolute and apparent magnitudes of Cepheids, we can measure their distances (using the 1/d2 law)! The Cepheid distance measurements were the first distance determinations that worked out to distances beyond our Milky Way! Cepheids are up to ~ 40,000 times more luminous than our sun => can ...
... Comparing absolute and apparent magnitudes of Cepheids, we can measure their distances (using the 1/d2 law)! The Cepheid distance measurements were the first distance determinations that worked out to distances beyond our Milky Way! Cepheids are up to ~ 40,000 times more luminous than our sun => can ...
The Milky Way - 清華大學物理系歡迎頁 Welcome to
... Comparing absolute and apparent magnitudes of Cepheids, we can measure their distances (using the 1/d2 law)! The Cepheid distance measurements were the first distance determinations that worked out to distances beyond our Milky Way! Cepheids are up to ~ 40,000 times more luminous than our sun => can ...
... Comparing absolute and apparent magnitudes of Cepheids, we can measure their distances (using the 1/d2 law)! The Cepheid distance measurements were the first distance determinations that worked out to distances beyond our Milky Way! Cepheids are up to ~ 40,000 times more luminous than our sun => can ...
galaxy_physics
... – About 10% of star mass – Collisional lose energy by radiation – Can settle to bottom of potential and make stars • Disk plane : gas creates disk stars (“cold” with small scale height) ...
... – About 10% of star mass – Collisional lose energy by radiation – Can settle to bottom of potential and make stars • Disk plane : gas creates disk stars (“cold” with small scale height) ...
Why is there a main sequence?
... Mmax ~ 100 solar masses a) More massive clouds fragment into smaller pieces during star formation ...
... Mmax ~ 100 solar masses a) More massive clouds fragment into smaller pieces during star formation ...
March
... adjoining galaxy M82 had a close encounter about 600 million years ago, resulting in a prolonged period of intense new star formation that continues today. This is a prime candidate for the east scope. M82 is an irregular galaxy of 8th magnitude in the constellation Ursa Major (URR-suh-MAY-jer). Als ...
... adjoining galaxy M82 had a close encounter about 600 million years ago, resulting in a prolonged period of intense new star formation that continues today. This is a prime candidate for the east scope. M82 is an irregular galaxy of 8th magnitude in the constellation Ursa Major (URR-suh-MAY-jer). Als ...
Astrophysics - Florence
... Our Sun is just one out of over 200 billion stars in our galaxy, the Milky Way. The Sun is located in the Orion arm of our galaxy about 25,000 light years from the center of the Galaxy. Kepler will be examining over 100,000 stars in our neighborhood of our galaxy in the Cygnus and Lyra constellation ...
... Our Sun is just one out of over 200 billion stars in our galaxy, the Milky Way. The Sun is located in the Orion arm of our galaxy about 25,000 light years from the center of the Galaxy. Kepler will be examining over 100,000 stars in our neighborhood of our galaxy in the Cygnus and Lyra constellation ...
RR animation
... and consequently, they were once stars with similar or slightly less mass than the Sun, around 0.8 solar masses. RR Lyrae stars pulse in a manner similar to Cepheid variables, so the mechanism for the pulsation is thought to be similar, but the nature and histories of these stars is thought to be ra ...
... and consequently, they were once stars with similar or slightly less mass than the Sun, around 0.8 solar masses. RR Lyrae stars pulse in a manner similar to Cepheid variables, so the mechanism for the pulsation is thought to be similar, but the nature and histories of these stars is thought to be ra ...
Small Wonders: Taurus
... and high contrast. When embarked on your own investigation into the Pleiades nebulosity use low powers. Pay careful attention to the area around Merope - where the brightest swatch of nebula resides (the Merope Nebula). On a good night you may see nebulosity throughout the cluster. Be aware that a s ...
... and high contrast. When embarked on your own investigation into the Pleiades nebulosity use low powers. Pay careful attention to the area around Merope - where the brightest swatch of nebula resides (the Merope Nebula). On a good night you may see nebulosity throughout the cluster. Be aware that a s ...
SM_Taurus - Cloudy Nights
... and high contrast. When embarked on your own investigation into the Pleiades nebulosity use low powers. Pay careful attention to the area around Merope - where the brightest swatch of nebula resides (the Merope Nebula). On a good night you may see nebulosity throughout the cluster. Be aware that a s ...
... and high contrast. When embarked on your own investigation into the Pleiades nebulosity use low powers. Pay careful attention to the area around Merope - where the brightest swatch of nebula resides (the Merope Nebula). On a good night you may see nebulosity throughout the cluster. Be aware that a s ...
astrocoursespring2012lec1-1-5
... -minor errata They point to the cross-over point of the analemma as the the equinox. This is not the case. The equinox occurs halfway between the most northern, and south excursion of the Sun ...
... -minor errata They point to the cross-over point of the analemma as the the equinox. This is not the case. The equinox occurs halfway between the most northern, and south excursion of the Sun ...
Lecture 17: General Relativity and Black Holes
... 33. The approximate number of stars in our galaxy? _______ 24. The approximate diameter of our own galaxy? _______ 25. The galactic north pole is in what constellation? _______ 1. The Sun is located at the center of the Milky Way Galaxy. True or false 2. Shapley overestimated the dimensions of the M ...
... 33. The approximate number of stars in our galaxy? _______ 24. The approximate diameter of our own galaxy? _______ 25. The galactic north pole is in what constellation? _______ 1. The Sun is located at the center of the Milky Way Galaxy. True or false 2. Shapley overestimated the dimensions of the M ...
Project 5: Globular cluster
... by gravity. Globular clusters orbit around the Milky Way galaxy core like satellites. The number of stars in a globular cluster varies from a few thousand up to a million stars for the more massive ones. There are ~150 known globular clusters that orbit our own Milky Way galaxy cor ...
... by gravity. Globular clusters orbit around the Milky Way galaxy core like satellites. The number of stars in a globular cluster varies from a few thousand up to a million stars for the more massive ones. There are ~150 known globular clusters that orbit our own Milky Way galaxy cor ...
Star Clusters in Mergers
... In our 1999 paper, one of our primary difficulties was differentiating stars from clusters. This led us to conclude that the number of young star clusters in the Antennae was between 800 and 8000, a pretty big range ! Our new ACS data provides a better opportunity for making this determination, and ...
... In our 1999 paper, one of our primary difficulties was differentiating stars from clusters. This led us to conclude that the number of young star clusters in the Antennae was between 800 and 8000, a pretty big range ! Our new ACS data provides a better opportunity for making this determination, and ...
The Solar Neighborhood
... The globular star clusters are bright, and can be seen for a long distance. Their distances can be estimated accurately from their main sequence turnoffs, as well as by measuring the periods of variable stars that belong to each cluster. In the table below are listed several dozen Galactic globular ...
... The globular star clusters are bright, and can be seen for a long distance. Their distances can be estimated accurately from their main sequence turnoffs, as well as by measuring the periods of variable stars that belong to each cluster. In the table below are listed several dozen Galactic globular ...
HR Diagram of a Star Cluster
... A cluster of stars which is localized in space is usually localized in time also. Surprisingly, the brightness (magnitude) of the stars in two different color bands can be interpreted to tell the cluster's age and distance from Earth. This is done by plotting a magnitude vs. color diagram (as Hertzs ...
... A cluster of stars which is localized in space is usually localized in time also. Surprisingly, the brightness (magnitude) of the stars in two different color bands can be interpreted to tell the cluster's age and distance from Earth. This is done by plotting a magnitude vs. color diagram (as Hertzs ...
Document
... more rapidly than average will escape, or “evaporate,” from such a cluster • A stellar association is a group of newborn stars that are moving apart so rapidly that their gravitational attraction for one another cannot pull them into orbit about one another ...
... more rapidly than average will escape, or “evaporate,” from such a cluster • A stellar association is a group of newborn stars that are moving apart so rapidly that their gravitational attraction for one another cannot pull them into orbit about one another ...
Some Examples of Virtual Observatory Enabled Science What Are the Some Distinguishing
... • Only ~ 10 - 20% of galaxies live in clusters, but it is hard to draw the line between groups and clusters, and at least ~50% of all galaxies are in clusters or groups • Clusters have higher densities than groups, contain a majority of E’s and S0’s while groups are dominated by spirals • Interestin ...
... • Only ~ 10 - 20% of galaxies live in clusters, but it is hard to draw the line between groups and clusters, and at least ~50% of all galaxies are in clusters or groups • Clusters have higher densities than groups, contain a majority of E’s and S0’s while groups are dominated by spirals • Interestin ...
Study Guide 4 Part A Outline
... from the center. o This all culminated in the Curtis-Shapley debate (1920). The issues were: The position of the Sun within our Galaxy. The size of our galaxy. Are there other galaxies outside our own Galaxy? o Each side had it partly right. Our Milky Way Galaxy o Parts of the Milky Way Disk ...
... from the center. o This all culminated in the Curtis-Shapley debate (1920). The issues were: The position of the Sun within our Galaxy. The size of our galaxy. Are there other galaxies outside our own Galaxy? o Each side had it partly right. Our Milky Way Galaxy o Parts of the Milky Way Disk ...
giant molecular clouds
... Protostars Protostars = pre-birth state of stars: Hydrogen to Helium fusion not yet ignited ...
... Protostars Protostars = pre-birth state of stars: Hydrogen to Helium fusion not yet ignited ...
Globular Clusters - Lick Observatory
... We took pictures with three different filters because CCD are color blind so we make them see color by using as filter. We took a long exposure to see faint stars and short exposure so we wouldn’t over saturate the picture. ...
... We took pictures with three different filters because CCD are color blind so we make them see color by using as filter. We took a long exposure to see faint stars and short exposure so we wouldn’t over saturate the picture. ...
Problem Set 6 for Astro 320 Read sections 11.2
... e.g. the KH timescale is calculated for the star, assuming constant density, rather than its core), but they are within a factor of 20. Problem 4: C& O, problem 13.11. a) The main sequence lifetime of a 0.8 M star is, from Table 13.1, about 25 billion years (depending on whether point 2 or 3 is cho ...
... e.g. the KH timescale is calculated for the star, assuming constant density, rather than its core), but they are within a factor of 20. Problem 4: C& O, problem 13.11. a) The main sequence lifetime of a 0.8 M star is, from Table 13.1, about 25 billion years (depending on whether point 2 or 3 is cho ...
Open cluster
An open cluster, also known as galactic cluster, is a group of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way Galaxy, and many more are thought to exist. They are loosely bound by mutual gravitational attraction and become disrupted by close encounters with other clusters and clouds of gas as they orbit the galactic center, resulting in a migration to the main body of the galaxy as well as a loss of cluster members through internal close encounters. Open clusters generally survive for a few hundred million years, with the most massive ones surviving for a few billion years. In contrast, the more massive globular clusters of stars exert a stronger gravitational attraction on their members, and can survive for longer. Open clusters have been found only in spiral and irregular galaxies, in which active star formation is occurring.Young open clusters may still be contained within the molecular cloud from which they formed, illuminating it to create an H II region. Over time, radiation pressure from the cluster will disperse the molecular cloud. Typically, about 10% of the mass of a gas cloud will coalesce into stars before radiation pressure drives the rest of the gas away.Open clusters are key objects in the study of stellar evolution. Because the cluster members are of similar age and chemical composition, their properties (such as distance, age, metallicity and extinction) are more easily determined than they are for isolated stars. A number of open clusters, such as the Pleiades, Hyades or the Alpha Persei Cluster are visible with the naked eye. Some others, such as the Double Cluster, are barely perceptible without instruments, while many more can be seen using binoculars or telescopes. The Wild Duck Cluster, M11, is an example.