Foundation 1 - Discovering Astronomy
... • While the exterior layers expand, the helium core continues to contract and eventually becomes hot enough (100 million kelvins) for helium to begin to fuse into carbon and oxygen – core helium fusion – 3 He C + energy and C + He O + energy – occurs rapidly - called the Helium Flash ...
... • While the exterior layers expand, the helium core continues to contract and eventually becomes hot enough (100 million kelvins) for helium to begin to fuse into carbon and oxygen – core helium fusion – 3 He C + energy and C + He O + energy – occurs rapidly - called the Helium Flash ...
Star Life Cycles WS
... 2) In a stable star, the ____________ pushing out from the center is equal with the ___________pulling atoms inward to the center – when these forces are equal, the star is at equilibrium. 3. There are three main fuels that a star uses for fusion: ___________, then ___________, and finally _________ ...
... 2) In a stable star, the ____________ pushing out from the center is equal with the ___________pulling atoms inward to the center – when these forces are equal, the star is at equilibrium. 3. There are three main fuels that a star uses for fusion: ___________, then ___________, and finally _________ ...
Astronomy Notes
... the case of our Sun approximately 98% of the matter in the nebula became the star). This collapsing mass is under great pressure and heats up and is called a _____________. (This kind of temperature change is called an ___________ ____________ ______) 4. ________________________ - if the core of thi ...
... the case of our Sun approximately 98% of the matter in the nebula became the star). This collapsing mass is under great pressure and heats up and is called a _____________. (This kind of temperature change is called an ___________ ____________ ______) 4. ________________________ - if the core of thi ...
The sun gives off energy all of the time
... The Drake equation brings out the importance of understanding how long an intelligent civilization exists. This relates to the life of a star. The sun's lifetime has been estimated from the fact that it gives off 3.9 x 1026 Watts (Joules/second), and comparing this luminosity to the energy avai ...
... The Drake equation brings out the importance of understanding how long an intelligent civilization exists. This relates to the life of a star. The sun's lifetime has been estimated from the fact that it gives off 3.9 x 1026 Watts (Joules/second), and comparing this luminosity to the energy avai ...
Astronomy – Interpreting Main Sequence Star Data The
... 3.a) How would our sun be classified? b) How long is the life time of our sun? c) As our sun ages how will it change? 4. Which star type in the table would be considered a dwarf star? Explain your answer. 5. Which star type is most similar to the Sun? Explain your answer. 6. Which star types are lik ...
... 3.a) How would our sun be classified? b) How long is the life time of our sun? c) As our sun ages how will it change? 4. Which star type in the table would be considered a dwarf star? Explain your answer. 5. Which star type is most similar to the Sun? Explain your answer. 6. Which star types are lik ...
Lecture Notes-PPT
... gas. After the remnant gas is heated and blow away, the stars collect together by gravity. During the exchange of energy between the stars, some stars reach escape velocity from the protocluster and become runaway stars. The rest become gravitationally bound, meaning they will exist as collection or ...
... gas. After the remnant gas is heated and blow away, the stars collect together by gravity. During the exchange of energy between the stars, some stars reach escape velocity from the protocluster and become runaway stars. The rest become gravitationally bound, meaning they will exist as collection or ...
Chapter 11 - USD Home Pages
... 15. Consider two identical stars, with one star 5 times farther away than the other. How much brighter will the closer star appear than the more distant one? Answer: Quoting from page 355, “Apparent brightness decreases inversely with the square of the distance...” So, the ratio of the distances is ...
... 15. Consider two identical stars, with one star 5 times farther away than the other. How much brighter will the closer star appear than the more distant one? Answer: Quoting from page 355, “Apparent brightness decreases inversely with the square of the distance...” So, the ratio of the distances is ...
Earth 351, Forming a Habitable Planet
... began with the accretion of the Earth and spans the periods of differentiation, heavy bombardment, and formation of the early atmosphere. - 2.5 Ga: End of the Archean Eon, by the end of which most of the continents formed and life appeared in the form of archaea and bacteria. - 542 Ga: End of the Pr ...
... began with the accretion of the Earth and spans the periods of differentiation, heavy bombardment, and formation of the early atmosphere. - 2.5 Ga: End of the Archean Eon, by the end of which most of the continents formed and life appeared in the form of archaea and bacteria. - 542 Ga: End of the Pr ...
1.1 Stars in the Broader Context of Modern Astro
... largest distances. At present, the record for the most distant known object in the Universe is held not by a galaxy, nor a quasar, but by a gamma-ray burst (GRB) at redshift z ∼ 9.4. A gamma-ray burst is thought to mark the end of a massive and rapidly rotating star, when its core collapses directly ...
... largest distances. At present, the record for the most distant known object in the Universe is held not by a galaxy, nor a quasar, but by a gamma-ray burst (GRB) at redshift z ∼ 9.4. A gamma-ray burst is thought to mark the end of a massive and rapidly rotating star, when its core collapses directly ...
Notes: 3.5 STAR EVOLUTION Name: ______ Star
... Ø Happens when the star runs out of HYDROGEN FUEL. Ø The star INCREASES in size Ø Small to average size stars become GIANT stars Ø Large Mass stars become SUPERGIANT. 5. Star Destruction-Planetary Nebula OR Supernova Once the star runs out of fuel for good it will be destroyed. Ø A PLANETARY NE ...
... Ø Happens when the star runs out of HYDROGEN FUEL. Ø The star INCREASES in size Ø Small to average size stars become GIANT stars Ø Large Mass stars become SUPERGIANT. 5. Star Destruction-Planetary Nebula OR Supernova Once the star runs out of fuel for good it will be destroyed. Ø A PLANETARY NE ...
Type II supernova
A Type II supernova (plural: supernovae or supernovas) results from the rapid collapse and violent explosion of a massive star. A star must have at least 8 times, and no more than 40–50 times, the mass of the Sun (M☉) for this type of explosion. It is distinguished from other types of supernovae by the presence of hydrogen in its spectrum. Type II supernovae are mainly observed in the spiral arms of galaxies and in H II regions, but not in elliptical galaxies.Stars generate energy by the nuclear fusion of elements. Unlike the Sun, massive stars possess the mass needed to fuse elements that have an atomic mass greater than hydrogen and helium, albeit at increasingly higher temperatures and pressures, causing increasingly shorter stellar life spans. The degeneracy pressure of electrons and the energy generated by these fusion reactions are sufficient to counter the force of gravity and prevent the star from collapsing, maintaining stellar equilibrium. The star fuses increasingly higher mass elements, starting with hydrogen and then helium, progressing up through the periodic table until a core of iron and nickel is produced. Fusion of iron or nickel produces no net energy output, so no further fusion can take place, leaving the nickel-iron core inert. Due to the lack of energy output allowing outward pressure, equilibrium is broken.When the mass of the inert core exceeds the Chandrasekhar limit of about 1.4 M☉, electron degeneracy alone is no longer sufficient to counter gravity and maintain stellar equilibrium. A cataclysmic implosion takes place within seconds, in which the outer core reaches an inward velocity of up to 23% of the speed of light and the inner core reaches temperatures of up to 100 billion kelvin. Neutrons and neutrinos are formed via reversed beta-decay, releasing about 1046 joules (100 foes) in a ten-second burst. The collapse is halted by neutron degeneracy, causing the implosion to rebound and bounce outward. The energy of this expanding shock wave is sufficient to accelerate the surrounding stellar material to escape velocity, forming a supernova explosion, while the shock wave and extremely high temperature and pressure briefly allow for theproduction of elements heavier than iron. Depending on initial size of the star, the remnants of the core form a neutron star or a black hole. Because of the underlying mechanism, the resulting nova is also described as a core-collapse supernova.There exist several categories of Type II supernova explosions, which are categorized based on the resulting light curve—a graph of luminosity versus time—following the explosion. Type II-L supernovae show a steady (linear) decline of the light curve following the explosion, whereas Type II-P display a period of slower decline (a plateau) in their light curve followed by a normal decay. Type Ib and Ic supernovae are a type of core-collapse supernova for a massive star that has shed its outer envelope of hydrogen and (for Type Ic) helium. As a result, they appear to be lacking in these elements.