Lecture 7
... Explosion of stellar core stellar core to form neutron star Absolute magnitudes from –16 to –20 (energy ~1044J) – e.g. China, SN of 1054 reached mV=-6 (remnant is Crab Nebula) Ejects a large fraction of original mass with v~5000-10000 km s-1 Seen in spiral galaxies only, especially in spiral arms… P ...
... Explosion of stellar core stellar core to form neutron star Absolute magnitudes from –16 to –20 (energy ~1044J) – e.g. China, SN of 1054 reached mV=-6 (remnant is Crab Nebula) Ejects a large fraction of original mass with v~5000-10000 km s-1 Seen in spiral galaxies only, especially in spiral arms… P ...
The Sun and the Stars
... core-bounce – contraction of core heats outer layers which burn explosively, star literally explodes as a Type II Supernova leaving dense core of neutrons (R~5km) – a neutron-star Simulations suggest initial shock wave may stall, neutrino trapping may help drive off outer layers. r-processes (rapid) ...
... core-bounce – contraction of core heats outer layers which burn explosively, star literally explodes as a Type II Supernova leaving dense core of neutrons (R~5km) – a neutron-star Simulations suggest initial shock wave may stall, neutrino trapping may help drive off outer layers. r-processes (rapid) ...
HW #8 Stellar Evolution I Solutions
... luminosity, radius and temperature while on the main sequence, because of the natural thermostat mechanism in main sequence stars. The thermostat mechanism acts to return the core fusion rates back to an equilibrium rate in the event of fluctuations in the core fusion rate. This is known as a negati ...
... luminosity, radius and temperature while on the main sequence, because of the natural thermostat mechanism in main sequence stars. The thermostat mechanism acts to return the core fusion rates back to an equilibrium rate in the event of fluctuations in the core fusion rate. This is known as a negati ...
(Science 2012) Gal-Yam
... (11). SN 2005ap is the first exand, in some cases, copious ultraviolet (UV) flux, ciple, almost all SLSNe belong to one of two ample of the class defined below as SLSN-I. On SLSN events may become useful cosmic beacons spectroscopic classes: type IIn (hydrogen-rich 18 November 2006, TSS detected a b ...
... (11). SN 2005ap is the first exand, in some cases, copious ultraviolet (UV) flux, ciple, almost all SLSNe belong to one of two ample of the class defined below as SLSN-I. On SLSN events may become useful cosmic beacons spectroscopic classes: type IIn (hydrogen-rich 18 November 2006, TSS detected a b ...
Astronomy 10 - UC Berkeley Astronomy w
... If the Sun suddenly became a black hole, the orbits of the planets would not change. The extreme effects of a black hole only occur near the horizon (3 km away for the Sun), and all the planets are much further. (20) page 342, question 19 The appearance of an X-ray source from a binary system shows ...
... If the Sun suddenly became a black hole, the orbits of the planets would not change. The extreme effects of a black hole only occur near the horizon (3 km away for the Sun), and all the planets are much further. (20) page 342, question 19 The appearance of an X-ray source from a binary system shows ...
Origin_of_Elements in the stars
... the helium ashes. The result is carbon nuclei and even more heat. The "second wind" of heat release will be furious, increasing the light emitted from the future Sun's surface by a thousand fold. Meanwhile, the same heat will cause the outer layers of the present Sun to expand and form a huge "red g ...
... the helium ashes. The result is carbon nuclei and even more heat. The "second wind" of heat release will be furious, increasing the light emitted from the future Sun's surface by a thousand fold. Meanwhile, the same heat will cause the outer layers of the present Sun to expand and form a huge "red g ...
Homework #9 (Ch. 21)
... How are nuclei heavier than iron formed? 12. Chaisson Review and Discussion 21.18 Why was supernova 1987A so important? 13. Chaisson Problem 21.7 A supernova’s energy is often compared to the total energy output of the sun over its lifetime. Using the sun’s current energy output, calculate its total ...
... How are nuclei heavier than iron formed? 12. Chaisson Review and Discussion 21.18 Why was supernova 1987A so important? 13. Chaisson Problem 21.7 A supernova’s energy is often compared to the total energy output of the sun over its lifetime. Using the sun’s current energy output, calculate its total ...
The Evolution of Low Mass Stars
... how they were given their name. We now know they they are unrelated to planets, but the term is still used. ...
... how they were given their name. We now know they they are unrelated to planets, but the term is still used. ...
The Origin of the Elements edited by David L. Alles Western Washington University
... result is carbon nuclei and even more heat. The "second wind" of heat release will be furious, increasing the light emitted from the future Sun's surface by a thousand fold. Meanwhile, the same heat will cause the outer layers of the present Sun to expand and form a huge "red giant". As stellar time ...
... result is carbon nuclei and even more heat. The "second wind" of heat release will be furious, increasing the light emitted from the future Sun's surface by a thousand fold. Meanwhile, the same heat will cause the outer layers of the present Sun to expand and form a huge "red giant". As stellar time ...
OUR UNIVERSE Problem Set 7 Solutions Question A1 Question A2
... temperature, the entire core will begin helium fusion nearly simultaneously in a so-called helium flash, which increases the size of the core such that the electrons are no longer degenerate. The expanded core cools allowing the star to collapse further to below red giant size. The core helium fusin ...
... temperature, the entire core will begin helium fusion nearly simultaneously in a so-called helium flash, which increases the size of the core such that the electrons are no longer degenerate. The expanded core cools allowing the star to collapse further to below red giant size. The core helium fusin ...
Nuclear fusion in stars
... 0.8 Msun, He ignition occurs. The star becomes a giant or supergiant and He synthesizes C in the “triplealpha” reaction: ...
... 0.8 Msun, He ignition occurs. The star becomes a giant or supergiant and He synthesizes C in the “triplealpha” reaction: ...
Astro 3 Spring, 2004 (Prof
... -- Both white dwarfs and neutron stars are composed of degenerate matter. The two populations of stars are as follows (this is important and comes up over and over again in the chapters dealing with galaxies!): -- Population I stars are young stars that have a lot of elements beyond hydrogen and hel ...
... -- Both white dwarfs and neutron stars are composed of degenerate matter. The two populations of stars are as follows (this is important and comes up over and over again in the chapters dealing with galaxies!): -- Population I stars are young stars that have a lot of elements beyond hydrogen and hel ...
Low Mass
... • Moves along asymptotic giant branch – expands and cools – luminosity increases – Cooling, condensed material gets pushed outward ...
... • Moves along asymptotic giant branch – expands and cools – luminosity increases – Cooling, condensed material gets pushed outward ...
Life and Evolution of a Massive Star
... • First discovered in the 60s by US spy satellites looking for nuclear bomb tests • Astronomers first thought GRBs were just more energetic versions of X-ray binaries – X-ray binaries are concentrated in the disk of the Milky Way – GRBs are not, so they must be extragalactic ...
... • First discovered in the 60s by US spy satellites looking for nuclear bomb tests • Astronomers first thought GRBs were just more energetic versions of X-ray binaries – X-ray binaries are concentrated in the disk of the Milky Way – GRBs are not, so they must be extragalactic ...
Stars and The Universe
... As the sun shrinks, it will compress itself. This will cause it to heat back up and turn from red to white. 13. Eventually, our sun will turn into a black dwarf. Why? The compression that heats up a white dwarf is the last energy source for the sun. After this energy is radiated into space, there wi ...
... As the sun shrinks, it will compress itself. This will cause it to heat back up and turn from red to white. 13. Eventually, our sun will turn into a black dwarf. Why? The compression that heats up a white dwarf is the last energy source for the sun. After this energy is radiated into space, there wi ...
supernova remnants
... the next few thousand years. SN 1987A observed in 1999, 2000 SNRs enrich the ISM by dispersing material produced both during the star’s life and at the moment of the SN event. About 2 per century for Milky Way (all types) ...
... the next few thousand years. SN 1987A observed in 1999, 2000 SNRs enrich the ISM by dispersing material produced both during the star’s life and at the moment of the SN event. About 2 per century for Milky Way (all types) ...
STARS
... • Core runs out of He, and is no longer able to fuse the remaining heavier elements • The star blows its outer layer away • The core remains behind and burns as a white dwarf • Eventually it cools to become a black dwarf ...
... • Core runs out of He, and is no longer able to fuse the remaining heavier elements • The star blows its outer layer away • The core remains behind and burns as a white dwarf • Eventually it cools to become a black dwarf ...
Astronomy 103: Midterm 2 Answers Correct answer in bold
... 28. The planets Londinium and Bellerophon orbit a star called the White Sun. Londinium is 1 AU from the star, and Bellerophon is 10 AU away. The brightness of light from the White Sun on Londinium is about 100 watt/meter2. What is the brightness of light from the White Sun on Bellerophon? ...
... 28. The planets Londinium and Bellerophon orbit a star called the White Sun. Londinium is 1 AU from the star, and Bellerophon is 10 AU away. The brightness of light from the White Sun on Londinium is about 100 watt/meter2. What is the brightness of light from the White Sun on Bellerophon? ...
HW #9 Answers (Due 10/28)
... cool to a certain temperature. There are no white dwarf stars cooler than about spectral type K. This is because there hasn’t been enough time for them to cool any further since the start of the universe. Knowing the cooling rate, and the cutoff in temperature for the white dwarfs, gives an age for ...
... cool to a certain temperature. There are no white dwarf stars cooler than about spectral type K. This is because there hasn’t been enough time for them to cool any further since the start of the universe. Knowing the cooling rate, and the cutoff in temperature for the white dwarfs, gives an age for ...
HW9_Answers
... cool to a certain temperature. There are no white dwarf stars cooler than about spectral type K. This is because there hasn’t been enough time for them to cool any further since the start of the universe. Knowing the cooling rate, and the cutoff in temperature for the white dwarfs, gives an age for ...
... cool to a certain temperature. There are no white dwarf stars cooler than about spectral type K. This is because there hasn’t been enough time for them to cool any further since the start of the universe. Knowing the cooling rate, and the cutoff in temperature for the white dwarfs, gives an age for ...
The Triple-Ring Nebula: Fingerprint of a Binary Merger
... for the progenitor8 . In this model, the system consisted initially of two massive stars, one with a mass of 15 – 20 times the mass of the Sun and a less massive companion with a mass of times the mass of the Sun. The two stars were orbiting each other with a period of at least 10 years (i.e. it t ...
... for the progenitor8 . In this model, the system consisted initially of two massive stars, one with a mass of 15 – 20 times the mass of the Sun and a less massive companion with a mass of times the mass of the Sun. The two stars were orbiting each other with a period of at least 10 years (i.e. it t ...
Stan Woosley (UCSC)
... And so – maybe – most massive stars blow up the way Hans and others talked about: Rotation and magnetic fields unimportant in the explosion (but might be important after an explosion is launched) Kicks and polarization from “spontaenous symmetry breaking” in conditions that started spherical. ...
... And so – maybe – most massive stars blow up the way Hans and others talked about: Rotation and magnetic fields unimportant in the explosion (but might be important after an explosion is launched) Kicks and polarization from “spontaenous symmetry breaking” in conditions that started spherical. ...
The Life of Stars
... Every atom in your body was made by a star! “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, and the carbon in our apple pies were all made in the interior of collapsing stars. We are made of ...
... Every atom in your body was made by a star! “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, and the carbon in our apple pies were all made in the interior of collapsing stars. We are made of ...
Supernova
A supernova is a stellar explosion that briefly outshines an entire galaxy, radiating as much energy as the Sun or any ordinary star is expected to emit over its entire life span, before fading from view over several weeks or months. The extremely luminous burst of radiation expels much or all of a star's material at a velocity of up to 7007300000000000000♠30,000 km/s (10% of the speed of light), driving a shock wave into the surrounding interstellar medium. This shock wave sweeps up an expanding shell of gas and dust called a supernova remnant. Supernovae are potentially strong galactic sources of gravitational waves. A great proportion of primary cosmic rays comes from supernovae.Supernovae are more energetic than novae. Nova means ""new"" in Latin, referring to what appears to be a very bright new star shining in the celestial sphere; the prefix ""super-"" distinguishes supernovae from ordinary novae, which are far less luminous. The word supernova was coined by Walter Baade and Fritz Zwicky in 1931. It is pronounced /ˌsuːpərnoʊvə/ with the plural supernovae /ˌsuːpərnoʊviː/ or supernovas (abbreviated SN, plural SNe after ""supernovae"").Supernovae can be triggered in one of two ways: by the sudden re-ignition of nuclear fusion in a degenerate star; or by the gravitational collapse of the core of a massive star. In the first case, a degenerate white dwarf may accumulate sufficient material from a companion, either through accretion or via a merger, to raise its core temperature, ignite carbon fusion, and trigger runaway nuclear fusion, completely disrupting the star. In the second case, the core of a massive star may undergo sudden gravitational collapse, releasing gravitational potential energy that can create a supernova explosion.The most recent directly observed supernova in the Milky Way was Kepler's Star of 1604 (SN 1604); remnants of two more recent supernovae have been found retrospectively. Observations in other galaxies indicate that supernovae should occur on average about three times every century in the Milky Way, and that any galactic supernova would almost certainly be observable in modern astronomical equipment. Supernovae play a significant role in enriching the interstellar medium with higher mass elements. Furthermore, the expanding shock waves from supernova explosions can trigger the formation of new stars.