Stellar Evolution and the Herzsprung-Russell Diagram
... A star is a massive, self-luminous ball of gas held together by its self-gravity, and that shines, or used to shine, due to energy released by nuclear reactions in its core. Self-luminous: not reflecting light like a planet. Shines because it is HOT (not because of nuclear reactions). Nuclear bombs ...
... A star is a massive, self-luminous ball of gas held together by its self-gravity, and that shines, or used to shine, due to energy released by nuclear reactions in its core. Self-luminous: not reflecting light like a planet. Shines because it is HOT (not because of nuclear reactions). Nuclear bombs ...
Written by G. Jeffrey Taylor
... ome presolar grains found in meteorites have isotopic compositions of silicon, carbon, and other elements predicted for formation in material flowing from asymptotic giant branch starts, nicknamed AGB stars. Stars with masses not too much different from the Sun reach this stage after using up all th ...
... ome presolar grains found in meteorites have isotopic compositions of silicon, carbon, and other elements predicted for formation in material flowing from asymptotic giant branch starts, nicknamed AGB stars. Stars with masses not too much different from the Sun reach this stage after using up all th ...
17Nov_2014
... predictable curve – Initial brightness increase followed by a slowly decaying “tail” ...
... predictable curve – Initial brightness increase followed by a slowly decaying “tail” ...
Evolution of High
... is not too heavy. • The core becomes a neutron star with a mass of about 1 Msun, with a size of just a few kilometer! (Chapter 13) • If the mass of the star is high enough to overcome the neutron degenerate pressure, then the core collapse into a black hole! (Chapter 13) • In either cases, the energ ...
... is not too heavy. • The core becomes a neutron star with a mass of about 1 Msun, with a size of just a few kilometer! (Chapter 13) • If the mass of the star is high enough to overcome the neutron degenerate pressure, then the core collapse into a black hole! (Chapter 13) • In either cases, the energ ...
stars - allenscience
... massive explosion called a Supernova. The end result is also a planetary nebula. Supernova are so bright that they can outshine an entire galaxy for a period of time. ...
... massive explosion called a Supernova. The end result is also a planetary nebula. Supernova are so bright that they can outshine an entire galaxy for a period of time. ...
2009 Assessment Schedule (90764)
... When the mass of the protostar is sufficiently high it enables the nuclear fusion of hydrogen into helium and becomes a main sequence star. AND Gravitational collapse explained using one or more causes stated below. Gravitational collapse can be caused by: • giant molecular clouds colliding, • passi ...
... When the mass of the protostar is sufficiently high it enables the nuclear fusion of hydrogen into helium and becomes a main sequence star. AND Gravitational collapse explained using one or more causes stated below. Gravitational collapse can be caused by: • giant molecular clouds colliding, • passi ...
Einstein
... light is emitted by charged particles moving close to the speed of light around magnetic fields. • Emission (mostly radio) is concentrated at the magnetic poles and focused into a beam. • Whether we see a pulsar depends on the geometry. – if the polar beam sweeps by Earth’s direction once each rotat ...
... light is emitted by charged particles moving close to the speed of light around magnetic fields. • Emission (mostly radio) is concentrated at the magnetic poles and focused into a beam. • Whether we see a pulsar depends on the geometry. – if the polar beam sweeps by Earth’s direction once each rotat ...
Slide 1
... • The sun is a relatively small star: its core won’t get hot enough to fuse elements beyond carbon • Bigger stars, greater than about 8 solar masses, also expand, to become supergiants • In these, core temperatures may exceed 3 billion degrees and more complex fusion reactions can occur, forming eve ...
... • The sun is a relatively small star: its core won’t get hot enough to fuse elements beyond carbon • Bigger stars, greater than about 8 solar masses, also expand, to become supergiants • In these, core temperatures may exceed 3 billion degrees and more complex fusion reactions can occur, forming eve ...
The Galactic Super Star Cluster Westerlund 1
... times the mass of Orion. Therefore, we would have expected diffuse emission with L x = 3x10 35 erg s-1, which is five times more flux than we observe. We suggest that the IMF is nonstandard, as is often claimed for young, massive star clusters. ...
... times the mass of Orion. Therefore, we would have expected diffuse emission with L x = 3x10 35 erg s-1, which is five times more flux than we observe. We suggest that the IMF is nonstandard, as is often claimed for young, massive star clusters. ...
Brock physics - Brock University
... (c) the radius of the region around a neutron star within which X-ray bursts occur. (d) * the radius of the region around a black hole within which not even light can escape. ...
... (c) the radius of the region around a neutron star within which X-ray bursts occur. (d) * the radius of the region around a black hole within which not even light can escape. ...
Stellar Evolution
... per cubic centimeter (in English about 30 billion trillion). Most solids and liquids have similar numbers. At the earth’s surface our atmosphere has about 2.4 x 1019 molecules per cubic centimeter (about a thousand times less dense than liquid water). In most of interstellar space, there is about 1 ...
... per cubic centimeter (in English about 30 billion trillion). Most solids and liquids have similar numbers. At the earth’s surface our atmosphere has about 2.4 x 1019 molecules per cubic centimeter (about a thousand times less dense than liquid water). In most of interstellar space, there is about 1 ...
COSMOLOGY 1 An Introduction to the Universe
... the star's outer layers, the material is heated, fusing to form new elements and radioactive isotopes. While many of the more common elements are made through nuclear fusion in the cores of stars, it takes the unstable conditions of the supernova explosion to form many of the heavier elements. The s ...
... the star's outer layers, the material is heated, fusing to form new elements and radioactive isotopes. While many of the more common elements are made through nuclear fusion in the cores of stars, it takes the unstable conditions of the supernova explosion to form many of the heavier elements. The s ...
Supernovae
... inverse b-decay Neutrinos carry energy out of the star and provide momentum through collisions to throw off material. Or they heat the material so that it expands. They have no mass (like photons) and can traverse large depths without being absorbed. ...
... inverse b-decay Neutrinos carry energy out of the star and provide momentum through collisions to throw off material. Or they heat the material so that it expands. They have no mass (like photons) and can traverse large depths without being absorbed. ...
Other Galaxies, their Distances, and the Expansion of the Universe
... Brian Schmidt Adam Riess Type 1a Supernovae show that the Universe is accelerating! ...
... Brian Schmidt Adam Riess Type 1a Supernovae show that the Universe is accelerating! ...
Review: How does a star*s mass determine its life story?
... • ___-mass stars have ____ lives, never become hot enough to fuse carbon nuclei, and end as white ...
... • ___-mass stars have ____ lives, never become hot enough to fuse carbon nuclei, and end as white ...
Evolution of a Low-Mass Star
... km/sec). "Planetary Nebula" (Historical name, nothing to do with planets.) Shine due to ionizing radiation from the hot core of the star embedded in a cool gas cloud. - Carbon core called a “White Dwarf” - shines only by stored heat, no more nuclear reactions. About the size of Earth. Cools to becom ...
... km/sec). "Planetary Nebula" (Historical name, nothing to do with planets.) Shine due to ionizing radiation from the hot core of the star embedded in a cool gas cloud. - Carbon core called a “White Dwarf” - shines only by stored heat, no more nuclear reactions. About the size of Earth. Cools to becom ...
The Hidden Lives of Galaxies NSTA 2001
... elements. Iron is the most stable element and cannot be fused further. Instead of releasing energy, it uses energy. ...
... elements. Iron is the most stable element and cannot be fused further. Instead of releasing energy, it uses energy. ...
The Life Cycles of Stars
... star that is 1.5 to 4 times as massive as our Sun ends up as a neutron star after the supernova. Neutron stars spin rapidly giving off radio waves. If the radio waves are emitted in pulses (due to the star’s spin), these neutron stars are called pulsars. The core of a massive star that has 8 or more ...
... star that is 1.5 to 4 times as massive as our Sun ends up as a neutron star after the supernova. Neutron stars spin rapidly giving off radio waves. If the radio waves are emitted in pulses (due to the star’s spin), these neutron stars are called pulsars. The core of a massive star that has 8 or more ...
PleistoceneSN_GSA-Sept2016_upload
... • This file is best viewed using the presentation view, since there are animations which obscure part of the text if viewed as a static slide. • Thanks for your interest in this work! ...
... • This file is best viewed using the presentation view, since there are animations which obscure part of the text if viewed as a static slide. • Thanks for your interest in this work! ...
Requiem for a Star
... • As a Main Sequence star can only use hydrogen as a fuel • When hydrogen is exhausted collapse of interior is inevitable • Increase in temperature caused by collapse suddenly ignites unprocessed hydrogen, causing star to expand to become red giant ...
... • As a Main Sequence star can only use hydrogen as a fuel • When hydrogen is exhausted collapse of interior is inevitable • Increase in temperature caused by collapse suddenly ignites unprocessed hydrogen, causing star to expand to become red giant ...
Linking Asteroids and Meteorites through Reflectance
... • Since the time required for a white dwarf to reach this state is calculated to be longer than the current age of the universe of 13.7 billion years, no black dwarfs are expected to exist in the universe yet ...
... • Since the time required for a white dwarf to reach this state is calculated to be longer than the current age of the universe of 13.7 billion years, no black dwarfs are expected to exist in the universe yet ...
Life Cycle of a Star notes
... As the protostar continues to collapse due to gravity, it will attract more atoms and continually increase in mass and density. The increased density and gravity will cause the core temperature to eventually rise. ...
... As the protostar continues to collapse due to gravity, it will attract more atoms and continually increase in mass and density. The increased density and gravity will cause the core temperature to eventually rise. ...
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.