![HR Diagram Lab](http://s1.studyres.com/store/data/002537435_1-6608c545d2fa4b91a02fd9a3499343a1-300x300.png)
HR Diagram Lab
... 13. As you can see from the Group 1 stars, the cooler or hotter a star is, the brighter it will be. The Group 2 and Group 3 stars do not follow this pattern. Hence, there must be something besides temperature that can affect how bright a star is. Describe your own theory about these stars (Group 2 a ...
... 13. As you can see from the Group 1 stars, the cooler or hotter a star is, the brighter it will be. The Group 2 and Group 3 stars do not follow this pattern. Hence, there must be something besides temperature that can affect how bright a star is. Describe your own theory about these stars (Group 2 a ...
Time traveller – Activity
... communicating over the large distances involved in astronomy. It takes time for light to reach us from a distant star so when we look at the night sky, we are looking into the past. For example, we see the star Sirius as it was 9 years ago. Since radio signals also travel at the speed of light, this ...
... communicating over the large distances involved in astronomy. It takes time for light to reach us from a distant star so when we look at the night sky, we are looking into the past. For example, we see the star Sirius as it was 9 years ago. Since radio signals also travel at the speed of light, this ...
Measuring colour in astronomy
... The spectrum of the Sun shows many absorption lines due to elements in its outer atmosphere. If we ignore these, the Sun’s spectrum is remarkably close to that of a perfect ‘black body’ at the same temperature. See the illustration above. By the term 'black body', scientists mean an object which wou ...
... The spectrum of the Sun shows many absorption lines due to elements in its outer atmosphere. If we ignore these, the Sun’s spectrum is remarkably close to that of a perfect ‘black body’ at the same temperature. See the illustration above. By the term 'black body', scientists mean an object which wou ...
Earth and Stars
... Measuring distances to objects within our Galaxy is not always a straightforward task - we cannot simply stretch out a measuring tape between two objects and read off the distance. Instead, a number of techniques have been developed that enable us to measure distances to stars without needing to lea ...
... Measuring distances to objects within our Galaxy is not always a straightforward task - we cannot simply stretch out a measuring tape between two objects and read off the distance. Instead, a number of techniques have been developed that enable us to measure distances to stars without needing to lea ...
Chapter 8 powerpoint presentation
... How many of the H atoms are in each of the excitation levels, n=1, n=2, etc, described by the Boltzmann equation and secondly, how many of the H atoms are completely ionized, for if the H atoms are ionized they can not produce any absorption lines. This is described by the Saha equation. ...
... How many of the H atoms are in each of the excitation levels, n=1, n=2, etc, described by the Boltzmann equation and secondly, how many of the H atoms are completely ionized, for if the H atoms are ionized they can not produce any absorption lines. This is described by the Saha equation. ...
Volume 2 (Issue 7), July 2013
... the universe. They show largest red-shift of any other objects in the cosmos. Astronomers are able to measure speed and distance of far away objects by measuring the spectrum of their light. If the colors of this spectrum are shifted toward the red, this means that the object is moving away from us. ...
... the universe. They show largest red-shift of any other objects in the cosmos. Astronomers are able to measure speed and distance of far away objects by measuring the spectrum of their light. If the colors of this spectrum are shifted toward the red, this means that the object is moving away from us. ...
Reading the Stars
... 1. Examine color-magnitude diagrams of clusters of stars. Since a cluster of stars is a group of stars that were formed at the same time from the same cloud of gas and dust, we can learn a lot about the stars within that cluster. A color-magnitude diagram is a kind of H-R Diagram. The horizontal axi ...
... 1. Examine color-magnitude diagrams of clusters of stars. Since a cluster of stars is a group of stars that were formed at the same time from the same cloud of gas and dust, we can learn a lot about the stars within that cluster. A color-magnitude diagram is a kind of H-R Diagram. The horizontal axi ...
The Family of Stars
... The flux received from both stars is the same, but star B is 5 times more luminous than star A, so star B must be further away. The flux received from both stars is the same, but star B is 100 times more luminous than star A, so star B must be further away. Both stars are equally luminous, but the f ...
... The flux received from both stars is the same, but star B is 5 times more luminous than star A, so star B must be further away. The flux received from both stars is the same, but star B is 100 times more luminous than star A, so star B must be further away. Both stars are equally luminous, but the f ...
PHYS-633: Problem set #0 Solutions
... f. Finally, generalize your analysis to derive an expression for how the extinction magnitude A, defined as the change in apparent magnitude m due to absorption, depends on the absorption optical depth τ to any star. Again, applying the magnitude definition, A ≡ ∆m = 2.5 log(eτ ) = 2.5τ log(e) = 1.0 ...
... f. Finally, generalize your analysis to derive an expression for how the extinction magnitude A, defined as the change in apparent magnitude m due to absorption, depends on the absorption optical depth τ to any star. Again, applying the magnitude definition, A ≡ ∆m = 2.5 log(eτ ) = 2.5τ log(e) = 1.0 ...
Basic Properties of Stars
... Hertzsprung-Russell Diagram Beware of the selection effects in the HR Diagram HR diagram of the brightest stars in the night sky. HR diagram of the stars nearest to the Sun. ...
... Hertzsprung-Russell Diagram Beware of the selection effects in the HR Diagram HR diagram of the brightest stars in the night sky. HR diagram of the stars nearest to the Sun. ...
color-stellar mass diagram
... viceversa in many cases (e.g. Lyα) number of absorption lines decreases due to the higher ionization level (proximity effect or inverse effect) to remove the effect, absorption systems within an appropriate velocity interval from QSO are excluded in the QSO rest-frame, a cloud moving toward the obse ...
... viceversa in many cases (e.g. Lyα) number of absorption lines decreases due to the higher ionization level (proximity effect or inverse effect) to remove the effect, absorption systems within an appropriate velocity interval from QSO are excluded in the QSO rest-frame, a cloud moving toward the obse ...
• This chapter concentrates on five goals:
... Temperature Spectral Classification The figure shows color images of 13 stellar spectra—ranging from the hottest at the top to the coolest at the bottom. ...
... Temperature Spectral Classification The figure shows color images of 13 stellar spectra—ranging from the hottest at the top to the coolest at the bottom. ...
The most important questions to study for the exam
... • It is the total energy emitted by the star per second, measured in joules/second or watts. • It is the apparent magnitude a star would have if it were at an infinite distance. • It is the apparent magnitude a star would have if it were at a standard distance of 10 pc. 13. According to the inverse- ...
... • It is the total energy emitted by the star per second, measured in joules/second or watts. • It is the apparent magnitude a star would have if it were at an infinite distance. • It is the apparent magnitude a star would have if it were at a standard distance of 10 pc. 13. According to the inverse- ...
Chapter 8: Stars
... • After the main-sequence stage, a star can enter the third stage of their life cycle. ...
... • After the main-sequence stage, a star can enter the third stage of their life cycle. ...
mam.evolution
... period P and separation a that obeys Kepler’s 3rd Law must have a total mass of 1 solar mass. c) Since we also know MA/MB = rA/rB, we can solve for masses. ...
... period P and separation a that obeys Kepler’s 3rd Law must have a total mass of 1 solar mass. c) Since we also know MA/MB = rA/rB, we can solve for masses. ...
31 — Main-Sequence Stars [Revision : 1.1]
... ∗ Higher luminosity means that CNO cycle must be used to match star’s energy generation needs ∗ High temperature sensitivity (∼ T 19 ) means centrally-concentrated energy generation ∗ So, luminosity Lr grows raidly in core, and F = Lr /4πr2 is large ∗ To transport all energy by radiation, temperatur ...
... ∗ Higher luminosity means that CNO cycle must be used to match star’s energy generation needs ∗ High temperature sensitivity (∼ T 19 ) means centrally-concentrated energy generation ∗ So, luminosity Lr grows raidly in core, and F = Lr /4πr2 is large ∗ To transport all energy by radiation, temperatur ...
Diapositiva 1
... The spectra of two nebulous objects near NGC 1999 (ApJ 113, 697). On a series of direct photographs taken with the Crosslyer reflector in 1946 and 1947 and centered on the diffuse nebula NGC 1999, there appear several peculiar nebulous objects. The brightest of these (referred to hereafter as "No. 1 ...
... The spectra of two nebulous objects near NGC 1999 (ApJ 113, 697). On a series of direct photographs taken with the Crosslyer reflector in 1946 and 1947 and centered on the diffuse nebula NGC 1999, there appear several peculiar nebulous objects. The brightest of these (referred to hereafter as "No. 1 ...
The Observable Universe: Redshift, Distances and the Hubble-Law
... • Measuring Hubble expansion needs to measure distances beyond Virgo cluster measure expansion of Coma cluster against Virgo! • SN Ia obviously are very good standard candles (since 1998) are observable for z < 2. • Calibration error < 0.1 mag possible? ...
... • Measuring Hubble expansion needs to measure distances beyond Virgo cluster measure expansion of Coma cluster against Virgo! • SN Ia obviously are very good standard candles (since 1998) are observable for z < 2. • Calibration error < 0.1 mag possible? ...
HR Diagram Activity - Mr. Alster`s Science Classes
... 13. As you can see from the Group 1 stars, the cooler or hotter a star is, the brighter it will be. The Group 2 and Group 3 stars do not follow this pattern. Hence, there must be something besides temperature that can affect how bright a star is. Describe your own theory about these stars (Group 2 a ...
... 13. As you can see from the Group 1 stars, the cooler or hotter a star is, the brighter it will be. The Group 2 and Group 3 stars do not follow this pattern. Hence, there must be something besides temperature that can affect how bright a star is. Describe your own theory about these stars (Group 2 a ...
Powerpoint Presentation (large file)
... of the atmosphere, are much more accurate than those made with Earth-based telescopes • Stellar parallaxes can only be measured for stars within a few hundred parsecs ...
... of the atmosphere, are much more accurate than those made with Earth-based telescopes • Stellar parallaxes can only be measured for stars within a few hundred parsecs ...
GEK - National University of Singapore
... 3) [Hubble’s Law and Cepheids] a) What is Hubble’s Law and how it changes our view on universe? Discuss. Hubble’s Law: Mathematically expresses the idea that more distant galaxies move away form us faster; its formula is ν=Ho x d, where ν is the galaxy’s speed away from us, d is its distance, and H ...
... 3) [Hubble’s Law and Cepheids] a) What is Hubble’s Law and how it changes our view on universe? Discuss. Hubble’s Law: Mathematically expresses the idea that more distant galaxies move away form us faster; its formula is ν=Ho x d, where ν is the galaxy’s speed away from us, d is its distance, and H ...
Climbing the Cosmic Distance Ladder: How Astronomers Measure
... Distances to very distant stars • This gave a way to obtain the absolute brightness for these stars, and hence observed distances. • Because Cepheids are so bright, this method works up to 13,000,000 light years, well beyond the Milky Way! Most galaxies are fortunate to have at least one ...
... Distances to very distant stars • This gave a way to obtain the absolute brightness for these stars, and hence observed distances. • Because Cepheids are so bright, this method works up to 13,000,000 light years, well beyond the Milky Way! Most galaxies are fortunate to have at least one ...
astrocoursespring2012lec4
... Recessional Velocity = Hubble's constant times distance V = Ho D In cosmological redshift, the wavelength at which the radiation is originally emitted is (only) lengthened as it travels through (expanding) space. A Cosmological redshift results from the expansion of space itself and not from the mot ...
... Recessional Velocity = Hubble's constant times distance V = Ho D In cosmological redshift, the wavelength at which the radiation is originally emitted is (only) lengthened as it travels through (expanding) space. A Cosmological redshift results from the expansion of space itself and not from the mot ...
Malmquist bias
The Malmquist bias is an effect in observational astronomy which leads to the preferential detection of intrinsically bright objects. It was first described in 1922 by Swedish astronomer Gunnar Malmquist (1893–1982), who then greatly elaborated upon this work in 1925. In statistics, this bias is referred to as a selection bias and affects the survey results in a brightness limited survey, where stars below a certain apparent brightness are not included. Since observed stars and galaxies appear dimmer when farther away, the brightness that is measured will fall off with distance until their brightness falls below the observational threshold. Objects which are more luminous, or intrinsically brighter, can be observed at a greater distance, creating a false trend of increasing intrinsic brightness, and other related quantities, with distance. This effect has led to many spurious claims in the field of astronomy. Properly correcting for these effects has become an area of great focus.