L5 - QUB Astrophysics Research Centre
... introductory articles provided, and supplement this with your own reading. You should attempt to clarify the problem for yourself and understand its importance. In particular you should discuss the following • Why and how have solar neutrinos been observed ? • What is their importance • Define and d ...
... introductory articles provided, and supplement this with your own reading. You should attempt to clarify the problem for yourself and understand its importance. In particular you should discuss the following • Why and how have solar neutrinos been observed ? • What is their importance • Define and d ...
Unit 11: Stellar Evolution
... distinct mass categories: very low mass (0.08 to 0.4 solar masses), low mass (0.4 to 9.0 solar masses), and high mass (9.0 to 60 solar masses). The physics of the deaths of very-low-mass stars is complicated. It is also hypothetical in the sense that their lifetimes exceed the age of the universe. B ...
... distinct mass categories: very low mass (0.08 to 0.4 solar masses), low mass (0.4 to 9.0 solar masses), and high mass (9.0 to 60 solar masses). The physics of the deaths of very-low-mass stars is complicated. It is also hypothetical in the sense that their lifetimes exceed the age of the universe. B ...
Nebulae
... The Sun is just a star, an average star. It just looks so big and bright, because it is so close, compared with other stars. ...
... The Sun is just a star, an average star. It just looks so big and bright, because it is so close, compared with other stars. ...
Chapter 17 Measuring the Stars
... shows the distribution of stellar masses. The more massive stars are much rarer than the least massive. ...
... shows the distribution of stellar masses. The more massive stars are much rarer than the least massive. ...
Absolute magnitude
... to jump to a higher energy level. ▪ The photon’s energy must be equal to the energy difference between the two levels. ...
... to jump to a higher energy level. ▪ The photon’s energy must be equal to the energy difference between the two levels. ...
Lecture 7
... • Why is the center of the Sun hot? • What is the source of the Sun’s energy? • What are neutrinos & why do we care • How does energy get from the inside to the outside of a star? ...
... • Why is the center of the Sun hot? • What is the source of the Sun’s energy? • What are neutrinos & why do we care • How does energy get from the inside to the outside of a star? ...
Astrophysics
... Supernovae explosions are the final act in the evolution of stars more massive than about 8 solar masses. Determining the progenitors of these explosive events and how massive stars are linked to the different SN types are topics of major significance for several fields of astrophysics. Recent obser ...
... Supernovae explosions are the final act in the evolution of stars more massive than about 8 solar masses. Determining the progenitors of these explosive events and how massive stars are linked to the different SN types are topics of major significance for several fields of astrophysics. Recent obser ...
Constellations and Asterisms
... Take a look to the northern night sky and try to pick out Ursa Major. Can you? The answer is most likely not. Partially due to light pollution on earth, it is terribly difficult view all the stars of Ursa Major as many of the stars either don’t have enough luminosity to stand out in our night sky or ...
... Take a look to the northern night sky and try to pick out Ursa Major. Can you? The answer is most likely not. Partially due to light pollution on earth, it is terribly difficult view all the stars of Ursa Major as many of the stars either don’t have enough luminosity to stand out in our night sky or ...
10.1 Introduction
... 10 000 K and then remain approximately constant at log L/L ' 5.7. Lamers and Fitzpatrick (1988) understood this behaviour in terms of the “Photospheric Eddington Limit”. The limits deduced above apply to the case when electron scattering is the only source of opacity. But in the atmospheres of even ...
... 10 000 K and then remain approximately constant at log L/L ' 5.7. Lamers and Fitzpatrick (1988) understood this behaviour in terms of the “Photospheric Eddington Limit”. The limits deduced above apply to the case when electron scattering is the only source of opacity. But in the atmospheres of even ...
It is only in the past few years that humanity... limits of the heliosphere. A fortunate confluence of missions has... 1. Magnetic Effects in the Heliosheath and Astrosheaths (Prof. Merav...
... Andrew West) Recent evidence suggests that at a given color or spectral type, magnetically active, low-mass stars may be more luminous than their inactive counterparts. The increase in luminosity could simply be due to spots on the surface making stars appear colder than their fundamental parameters ...
... Andrew West) Recent evidence suggests that at a given color or spectral type, magnetically active, low-mass stars may be more luminous than their inactive counterparts. The increase in luminosity could simply be due to spots on the surface making stars appear colder than their fundamental parameters ...
General Relativity
... Sun. This effect has been measured by bouncing radio waves off Mercury and Venus as they pass behind the Sun, and observing signals from solar system space craft. GR effects have been confirmed to an accuracy of 0.1% using these measurements. ...
... Sun. This effect has been measured by bouncing radio waves off Mercury and Venus as they pass behind the Sun, and observing signals from solar system space craft. GR effects have been confirmed to an accuracy of 0.1% using these measurements. ...
Notes
... Degenerate carbon-oxygen core, He- and H-burning shells, thin H layer, shrouded in dust from superwind (proto-planetary nebula) Mass loss rate decreases but wind speed increases Hydrogen layer thins further from mass loss and He burning shell Star evolves at constant luminosity (~104LSun), shrinking ...
... Degenerate carbon-oxygen core, He- and H-burning shells, thin H layer, shrouded in dust from superwind (proto-planetary nebula) Mass loss rate decreases but wind speed increases Hydrogen layer thins further from mass loss and He burning shell Star evolves at constant luminosity (~104LSun), shrinking ...
The birth and life of stars
... then to oxygen. In a massive giant, helium fusion begins gradually. In a less massive giant, it begins suddenly in a process called helium flash. The age of a stellar cluster can be estimated by plotting its stars on an H-R diagram. The upper portion of the main sequence disappears first, because ...
... then to oxygen. In a massive giant, helium fusion begins gradually. In a less massive giant, it begins suddenly in a process called helium flash. The age of a stellar cluster can be estimated by plotting its stars on an H-R diagram. The upper portion of the main sequence disappears first, because ...
Supernovae — Oct 21 10/21/2011 • Outline
... Pressure on the walls of the box is caused by the gas hitting the walls. Gas transfers momentum to the walls. Mental picture: Marbles hit the walls; wall pushes back. ...
... Pressure on the walls of the box is caused by the gas hitting the walls. Gas transfers momentum to the walls. Mental picture: Marbles hit the walls; wall pushes back. ...
Astronomy Glossary Key
... A black hole is a region in space with gravity so strong, not even light cans escape. Black holes are thought to be what is left after the collapse of a super giant star. In 1925 Hubble noticed that the spectra lines coming from hydrogen star light were all shifted toward the red end of the spectrum ...
... A black hole is a region in space with gravity so strong, not even light cans escape. Black holes are thought to be what is left after the collapse of a super giant star. In 1925 Hubble noticed that the spectra lines coming from hydrogen star light were all shifted toward the red end of the spectrum ...
Nucleosynthesis and Energy Production in Stars: Bethe`s Crowning
... of a proton and the deuteron to produce 3He and a '"'(ray. Two 3He nuclei, so produced, fuse to form a 4He and two protons. The net result is the consumption of 4 protons to form a 4He nucleus with the energy released being carried away by the particles and the '"'(-rays at each step of the sequence ...
... of a proton and the deuteron to produce 3He and a '"'(ray. Two 3He nuclei, so produced, fuse to form a 4He and two protons. The net result is the consumption of 4 protons to form a 4He nucleus with the energy released being carried away by the particles and the '"'(-rays at each step of the sequence ...
Stellar Evolution: Evolution: Birth, Life, and Death of Stars
... bigger than water. They are made of neutrons and more exotic particles. Young neutron stars rotate rapidly and emit regular pulses of radiation in radio, and are known as pulsars. ...
... bigger than water. They are made of neutrons and more exotic particles. Young neutron stars rotate rapidly and emit regular pulses of radiation in radio, and are known as pulsars. ...
1st EXAM VERSION C - Department of Physics and Astronomy
... spectral lines in atoms of the second star. C. The effect of the gravitational field of one star on the atoms of the second star produces spectral line shifts periodically. D. *Motion toward and away from Earth during their orbital motion results in Doppler shift of light from these stars at times a ...
... spectral lines in atoms of the second star. C. The effect of the gravitational field of one star on the atoms of the second star produces spectral line shifts periodically. D. *Motion toward and away from Earth during their orbital motion results in Doppler shift of light from these stars at times a ...
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 ...
Luminosity - UCF Physics
... Higher core temperature boosts fusion rate, leading to larger luminosity ...
... Higher core temperature boosts fusion rate, leading to larger luminosity ...
Today`s Powerpoint
... Mass of end products is less than mass of 4 protons by 0.7%. Mass converted to energy. 600 millions of tons per second fused. Takes billions of years to convert p's to 4He in Sun's core. Process sets lifetime of stars. Hydrostatic Equilibrium: pressure from fusion reactions balances gravity. Sun is ...
... Mass of end products is less than mass of 4 protons by 0.7%. Mass converted to energy. 600 millions of tons per second fused. Takes billions of years to convert p's to 4He in Sun's core. Process sets lifetime of stars. Hydrostatic Equilibrium: pressure from fusion reactions balances gravity. Sun is ...