Dark Matter in the Universe:
... Most (> 90%) of this mass is in the Dark Halo of the Galaxy, which extends out over 500,000 light-years from the center of the Galaxy -much further than the visible disk ...
... Most (> 90%) of this mass is in the Dark Halo of the Galaxy, which extends out over 500,000 light-years from the center of the Galaxy -much further than the visible disk ...
Part 1- The Basics
... Luminosity, Radius, and Surface Temperature • A more luminous star could be due to – Larger size (in radius) – Higher Surface Temperature • Example: The first magnitude reddish star Betelgeuse is 60,000 time more luminous than the Sun and has a surface temperature of 3500 K, what is its radius (in ...
... Luminosity, Radius, and Surface Temperature • A more luminous star could be due to – Larger size (in radius) – Higher Surface Temperature • Example: The first magnitude reddish star Betelgeuse is 60,000 time more luminous than the Sun and has a surface temperature of 3500 K, what is its radius (in ...
June 2016 night sky chart
... The star chart shows the stars and constellations visible in the night sky for Sydney, Melbourne, Canberra, Hobart and Adelaide for June 2016 at about 7:30 pm (local standard time). For Darwin and similar locations the chart will still apply, but some stars will be lost off the southern edge while e ...
... The star chart shows the stars and constellations visible in the night sky for Sydney, Melbourne, Canberra, Hobart and Adelaide for June 2016 at about 7:30 pm (local standard time). For Darwin and similar locations the chart will still apply, but some stars will be lost off the southern edge while e ...
Evolution Cycle of Stars
... • White dwarfs have a mass similar to that of the Sun, but only 1% of the Sun's diameter; approximately the diameter of the Earth. The surface temperature of a white dwarf is 8000C or more, but being smaller than the Sun their overall luminosity's are 1% of the Sun or less. • White dwarfs are the sh ...
... • White dwarfs have a mass similar to that of the Sun, but only 1% of the Sun's diameter; approximately the diameter of the Earth. The surface temperature of a white dwarf is 8000C or more, but being smaller than the Sun their overall luminosity's are 1% of the Sun or less. • White dwarfs are the sh ...
General Relativity
... between two objects that states the force of gravity depends on the mass of the two objects ...
... between two objects that states the force of gravity depends on the mass of the two objects ...
Stars
... Pulsars are Believed to be Rotating Neutron Stars As a star collapses in a supernova its magnetic field is prevserved, but intensified as it is squeezed into a smaller object. Similarly the neutron star will rotate, as did the original star, but much faster (think about a twirling ice skater). Char ...
... Pulsars are Believed to be Rotating Neutron Stars As a star collapses in a supernova its magnetic field is prevserved, but intensified as it is squeezed into a smaller object. Similarly the neutron star will rotate, as did the original star, but much faster (think about a twirling ice skater). Char ...
Steps
... Studies of galaxy evolution based on an “archaelogical” approach (stellar populations of present-day galaxies to infer the galaxy history – e.g. SDSS), or observing galaxies at earlier epochs (mainly snapshots of their evolution, eg. large spectroscopic surveys such as zCOSMOS, VIPERS). ...
... Studies of galaxy evolution based on an “archaelogical” approach (stellar populations of present-day galaxies to infer the galaxy history – e.g. SDSS), or observing galaxies at earlier epochs (mainly snapshots of their evolution, eg. large spectroscopic surveys such as zCOSMOS, VIPERS). ...
... be collected, since it still was in its gaseous state. This way the inner planets selectively were made out of heavy elements and thus have now high densities. At greater distance from the center, matter like water ice and methane ice could condense and more and more pieces could stick together. The ...
HR DIAGRAM REPORT FORM
... 5. Based on answers to 1-4 above fill in the blanks using close, hot or large. The twenty brightest stars in the night sky are most likely to be bright because they are _________ or __________ not because they are ____________. ...
... 5. Based on answers to 1-4 above fill in the blanks using close, hot or large. The twenty brightest stars in the night sky are most likely to be bright because they are _________ or __________ not because they are ____________. ...
Answer ALL questions from SECTION A and TWO questions from
... 10. Write an account of the pre-main sequence phase of stellar evolution from the point when hydrostatic equilibrium is established to arrival on the main sequence. Your account should describe the structure and the resulting evolutionary tracks of protostars during contraction to the main sequence. ...
... 10. Write an account of the pre-main sequence phase of stellar evolution from the point when hydrostatic equilibrium is established to arrival on the main sequence. Your account should describe the structure and the resulting evolutionary tracks of protostars during contraction to the main sequence. ...
Beyond the iron group: Heavy metals in hot subdwarfs
... other chemical peculiarities found in these stars. It has long been know that silicon in sdB stars show peculiar behaviour. Above a certain temperature (∼32 000 K) there is almost no silicon left in the upper photosphere. Previous studies suggested that above this temperature silicon might exist in ...
... other chemical peculiarities found in these stars. It has long been know that silicon in sdB stars show peculiar behaviour. Above a certain temperature (∼32 000 K) there is almost no silicon left in the upper photosphere. Previous studies suggested that above this temperature silicon might exist in ...
Support worksheet – Topic 3 Questions
... double the distance from Earth to star Y. Calculate the ratio of luminosities X . LY ...
... double the distance from Earth to star Y. Calculate the ratio of luminosities X . LY ...
Why do some galaxies stop making new stars?
... This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. ...
... This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. ...
!
... Cygnus X-1 is believed to be a black hole. Give two examples of how astronomers can (sometimes) determine whether an X-ray-emitting object is a neutron star or black hole. (2 points)! ...
... Cygnus X-1 is believed to be a black hole. Give two examples of how astronomers can (sometimes) determine whether an X-ray-emitting object is a neutron star or black hole. (2 points)! ...
Search for spectroscopical signatures of transiting HD 209458b`s
... – The ON/OFF transmission spectrum shows an absorption line at 6146.81 Å, where we expect an H2 O+ feature. The line is variable in time and most prominent in the ON spectra. One of the reference stars (HD 224926) also exhibits a similar feature at the same location and with similar width, which ma ...
... – The ON/OFF transmission spectrum shows an absorption line at 6146.81 Å, where we expect an H2 O+ feature. The line is variable in time and most prominent in the ON spectra. One of the reference stars (HD 224926) also exhibits a similar feature at the same location and with similar width, which ma ...
Problem Set 1 (due 2/21/06)
... triplet->singlet transition, but it need not be, generally speaking. c) resonance fluorescence Relaxation of an excited state by emission of a photon of the same frequency as the excitation frequency. This is more common in atoms than in molecules, which have vibrational relaxation pathways that may ...
... triplet->singlet transition, but it need not be, generally speaking. c) resonance fluorescence Relaxation of an excited state by emission of a photon of the same frequency as the excitation frequency. This is more common in atoms than in molecules, which have vibrational relaxation pathways that may ...
Stars and Deep Time
... • As this happens, the temperature falls and the volume decreases • This increases the pressure, but this raises the temperature and the volume starts to expand • At a critical point, a new phase begins— ‘He burning’ ...
... • As this happens, the temperature falls and the volume decreases • This increases the pressure, but this raises the temperature and the volume starts to expand • At a critical point, a new phase begins— ‘He burning’ ...
stellar_explosions - UT Austin (Astronomy)
... A.D. SN? Observed radial velocities of a few thousand km/sec gives age, which comes out to be about 950 years as it should. See Discovery 21-2 on p. 566. From the observed number of SNe (supernovae) in our own and other galaxies, we expect about 1 SN per 100 years in our Galaxy. But the last one was ...
... A.D. SN? Observed radial velocities of a few thousand km/sec gives age, which comes out to be about 950 years as it should. See Discovery 21-2 on p. 566. From the observed number of SNe (supernovae) in our own and other galaxies, we expect about 1 SN per 100 years in our Galaxy. But the last one was ...
ppt - SLAC
... powerful stellar wind. Wolf-Rayets are believed to be O stars that have lost their hydrogen envelopes, leaving their helium cores exposed, often in a binary system, and that are doomed, within a few million years, to explode as Type Ib or Ic supernovae. There are two spectral subclasses of Wolf-Raye ...
... powerful stellar wind. Wolf-Rayets are believed to be O stars that have lost their hydrogen envelopes, leaving their helium cores exposed, often in a binary system, and that are doomed, within a few million years, to explode as Type Ib or Ic supernovae. There are two spectral subclasses of Wolf-Raye ...
Astronomical spectroscopy
Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, which radiates from stars and other hot celestial objects. Spectroscopy can be used to derive many properties of distant stars and galaxies, such as their chemical composition, temperature, density, mass, distance, luminosity, and relative motion using Doppler shift measurements.