Announcements
... Visible (Balmer) lines of H due to Electron transitions to 2nd energy level Medium Temperature Stars (~104K) -> hot enough for collisions to knock electron up to 2nd level, not hot enough to knock electron free of atom. ...
... Visible (Balmer) lines of H due to Electron transitions to 2nd energy level Medium Temperature Stars (~104K) -> hot enough for collisions to knock electron up to 2nd level, not hot enough to knock electron free of atom. ...
Galaxies - schoolphysics
... gravity of the Earth. However if you jump up very fast - 40000 km/hour (25000 miles/hour) then you will never come down. You have reached the ESCAPE VELOCITY of the Earth Now the pull of gravity of a Black Hole is so huge that its escape velocity is as big as the speed of light. That’s why it’s blac ...
... gravity of the Earth. However if you jump up very fast - 40000 km/hour (25000 miles/hour) then you will never come down. You have reached the ESCAPE VELOCITY of the Earth Now the pull of gravity of a Black Hole is so huge that its escape velocity is as big as the speed of light. That’s why it’s blac ...
The Application of Forbidden Line X-Ray Diagnostics to the Hot Star
... X-Ray Diagnostics to the Hot Star Tau Sco ...
... X-Ray Diagnostics to the Hot Star Tau Sco ...
Stellar Evolution: Evolution: Birth, Life, and Death of Stars
... (brightness) as a function of temperature (spectral class); the ordinate "absolute magnitude" is a logarithmic measure of power. Most of the stars lie on the “main sequence”: massive stars are hot and have high power (top left), while the small stars have lower masses, are cold and have low power ...
... (brightness) as a function of temperature (spectral class); the ordinate "absolute magnitude" is a logarithmic measure of power. Most of the stars lie on the “main sequence”: massive stars are hot and have high power (top left), while the small stars have lower masses, are cold and have low power ...
Stars - Red, Blue, Old, New pt.4
... patterns of stars have depended strongly on mass, and the same goes for the final stages of evolution. • Stars do lose mass as they go from the main sequence through other stages. • Recall that the low mass stars are by far the ...
... patterns of stars have depended strongly on mass, and the same goes for the final stages of evolution. • Stars do lose mass as they go from the main sequence through other stages. • Recall that the low mass stars are by far the ...
Star Quiz - Sue Ryder
... What age are they, where are they based? • Next think about timing, what day of the week, and time of day will suit them? Is a week night or weekend better? • Think about your venue too. Will your guests bring children? If so an earlier time, and family friendly venue will be best. You could use a p ...
... What age are they, where are they based? • Next think about timing, what day of the week, and time of day will suit them? Is a week night or weekend better? • Think about your venue too. Will your guests bring children? If so an earlier time, and family friendly venue will be best. You could use a p ...
Stars III The Hertzsprung
... • The battle against gravity • Interstellar medium • Interstellar dust • Molecular clouds ...
... • The battle against gravity • Interstellar medium • Interstellar dust • Molecular clouds ...
Stellar Evolution
... and diameter. In fact, astronomers have discovered that the mass and the composition (makeup) of a star determine nearly all its other properties. ...
... and diameter. In fact, astronomers have discovered that the mass and the composition (makeup) of a star determine nearly all its other properties. ...
Lab 8: Stellar Classification and the H
... As early as the beginning of the 19th century, scientists have studied absorption spectra in an effort to classify stars. At first, spectra were divided into groups by general appearance; however, in the 1930’s and 1940’s, astronomers realized that spectral type was mainly determined by temperature ...
... As early as the beginning of the 19th century, scientists have studied absorption spectra in an effort to classify stars. At first, spectra were divided into groups by general appearance; however, in the 1930’s and 1940’s, astronomers realized that spectral type was mainly determined by temperature ...
Lecture 15: The Main Sequence
... More massive main-sequence stars need higher pressures to support themselves against gravitational collapse. Higher pressure=higher temperatures. The higher temperatures lead to greater rates of nuclear fusion which means higher luminosity. ...
... More massive main-sequence stars need higher pressures to support themselves against gravitational collapse. Higher pressure=higher temperatures. The higher temperatures lead to greater rates of nuclear fusion which means higher luminosity. ...
Linking Asteroids and Meteorites through Reflectance
... • If Earth orbited the Sun, ancient astronomers believed that they would see differences in angular separation of stars as the Earth rotated around the Sun • Since they saw no changes in angular separation of the stars, they assumed the Earth was the center of the universe • They could not fathom th ...
... • If Earth orbited the Sun, ancient astronomers believed that they would see differences in angular separation of stars as the Earth rotated around the Sun • Since they saw no changes in angular separation of the stars, they assumed the Earth was the center of the universe • They could not fathom th ...
Chapter 15: The Milky Way Galaxy
... How many stars does the Milky Way Galaxy contain? The Milky Way has about 200 billion stars. Where is our solar system located in the Milky Way Galaxy? The solar system is between the Sagittarius and Perseus spiral arms about 26,000 ly from the center of the Galaxy. Is the Sun moving through the Mil ...
... How many stars does the Milky Way Galaxy contain? The Milky Way has about 200 billion stars. Where is our solar system located in the Milky Way Galaxy? The solar system is between the Sagittarius and Perseus spiral arms about 26,000 ly from the center of the Galaxy. Is the Sun moving through the Mil ...
Chapter 17
... B. they are all at the same distance. C. they are all in the field of view of the galaxy center. D. as a class, they have similar luminosities. 17. The "orbits" of the stars in our galaxy do not follow the laws of Kepler. We understand this to be due to: A. proportionally more mass distributed away ...
... B. they are all at the same distance. C. they are all in the field of view of the galaxy center. D. as a class, they have similar luminosities. 17. The "orbits" of the stars in our galaxy do not follow the laws of Kepler. We understand this to be due to: A. proportionally more mass distributed away ...
Stellar Populations of Galaxies- 2 Lectures H
... The origin of the form of the IMF is not well understood Use the stellar mass-luminosity relation and present day stellar luminosity function together with a model of how the star formation rate varies ...
... The origin of the form of the IMF is not well understood Use the stellar mass-luminosity relation and present day stellar luminosity function together with a model of how the star formation rate varies ...
Reach_for_the_stars_final_questions.doc
... 13. For the sake of convenience, astronomers have divided the sky into 88 constellations. In which of these does the current Polar star, Polaris, lie? (1pt) ...
... 13. For the sake of convenience, astronomers have divided the sky into 88 constellations. In which of these does the current Polar star, Polaris, lie? (1pt) ...
Slide 1
... the hydrogen lines are weak. Both HeI and HeII (singly ionized helium) are seen in the higher temperature examples. The radiation from O5 stars is so intense that it can ionize hydrogen over a volume of space 1000 light years across. One example is the luminous H II region surrounding star cluster M ...
... the hydrogen lines are weak. Both HeI and HeII (singly ionized helium) are seen in the higher temperature examples. The radiation from O5 stars is so intense that it can ionize hydrogen over a volume of space 1000 light years across. One example is the luminous H II region surrounding star cluster M ...
Stellar kinematics
Stellar kinematics is the study of the movement of stars without needing to understand how they acquired their motion. This differs from stellar dynamics, which takes into account gravitational effects. The motion of a star relative to the Sun can provide useful information about the origin and age of a star, as well as the structure and evolution of the surrounding part of the Milky Way.In astronomy, it is widely accepted that most stars are born within molecular clouds known as stellar nurseries. The stars formed within such a cloud compose open clusters containing dozens to thousands of members. These clusters dissociate over time. Stars that separate themselves from the cluster's core are designated as members of the cluster's stellar association. If the remnant later drifts through the Milky Way as a coherent assemblage, then it is termed a moving group.