What do we mean by habitable zone?
... put a planet in that star’s habitable zone (which would be farther away because the star would be much more luminous than the Sun), life would be hard-pressed to evolve much even if it managed to originate. As a reminder, the earliest traces of life on Earth go back to something like 800 million ye ...
... put a planet in that star’s habitable zone (which would be farther away because the star would be much more luminous than the Sun), life would be hard-pressed to evolve much even if it managed to originate. As a reminder, the earliest traces of life on Earth go back to something like 800 million ye ...
Stars Student Page Purpose To investigate stellar classification by
... graph has an extremely high luminosity (wattage), but very low surface temperatures. Explain how this is possible. 4. The long line that extends from the upper left to the lower right portion of the graph is known as the Main Sequence. The majority of stars are found somewhere on this line. Develop ...
... graph has an extremely high luminosity (wattage), but very low surface temperatures. Explain how this is possible. 4. The long line that extends from the upper left to the lower right portion of the graph is known as the Main Sequence. The majority of stars are found somewhere on this line. Develop ...
Neutron Stars and Black Holes
... is about 0.877 X 10-13 cm (according to the Wikipedia). The volume of the proton is 4/3 π r3 = 2.82 X 10-39 cm3. The density = mass/volume = 5.9 X 1014 g/cm3. The Sun’s mass is 2 X 1030 kg = 2 X 1033 g. A one solar mass black hole has radius r ~ 3 km = 3 X 105 cm. The average mass within the Schwarz ...
... is about 0.877 X 10-13 cm (according to the Wikipedia). The volume of the proton is 4/3 π r3 = 2.82 X 10-39 cm3. The density = mass/volume = 5.9 X 1014 g/cm3. The Sun’s mass is 2 X 1030 kg = 2 X 1033 g. A one solar mass black hole has radius r ~ 3 km = 3 X 105 cm. The average mass within the Schwarz ...
14.5 Yellow Giants and Pulsating Stars Variable Stars Not all stars
... and Cepheid variables are usually yellow in color and lie along a narrow “instability strip” in the diagram. Page 375 Cepheid variables are yellow supergiants that are more massive than the Sun and range in luminosity from several hundred times the Sun's luminosity to several tens of thousands times ...
... and Cepheid variables are usually yellow in color and lie along a narrow “instability strip” in the diagram. Page 375 Cepheid variables are yellow supergiants that are more massive than the Sun and range in luminosity from several hundred times the Sun's luminosity to several tens of thousands times ...
Discussion Activity #9
... B. It is another name for the force that holds protons together in atomic nuclei. C. It describes the linkage between protons into long chains that occurs when temperatures are very high. D. It is another way of generating energy by nuclear fusion besides fusing hydrogen into helium. ...
... B. It is another name for the force that holds protons together in atomic nuclei. C. It describes the linkage between protons into long chains that occurs when temperatures are very high. D. It is another way of generating energy by nuclear fusion besides fusing hydrogen into helium. ...
Stars
... Many binaries are too far away to be resolved, but they can be discovered from periodic spectral line shifts. ...
... Many binaries are too far away to be resolved, but they can be discovered from periodic spectral line shifts. ...
Question paper - Edexcel
... D Star A has 8 times the luminosity of star B. (Total for Question 5 = 1 mark) 6 The electrostatic interaction between two charges and the gravitational interaction between two masses can be represented by similar equations. Which of the following is correct? A The force variation in both fields obe ...
... D Star A has 8 times the luminosity of star B. (Total for Question 5 = 1 mark) 6 The electrostatic interaction between two charges and the gravitational interaction between two masses can be represented by similar equations. Which of the following is correct? A The force variation in both fields obe ...
Stars Notes
... contracting gas and dust from a nebula become so dense and hot that nuclear fusion starts ...
... contracting gas and dust from a nebula become so dense and hot that nuclear fusion starts ...
Chapter 19 Star Formation
... Stars go through a number of stages in the process of forming from an interstellar cloud: [You don’t have to memorize these numbers, but they do tell an important story, and you should understand the names of the objects on the right.] ...
... Stars go through a number of stages in the process of forming from an interstellar cloud: [You don’t have to memorize these numbers, but they do tell an important story, and you should understand the names of the objects on the right.] ...
Chapter 19 Star Formation
... Stars go through a number of stages in the process of forming from an interstellar cloud: [You don’t have to memorize these numbers, but they do tell an important story, and you should understand the names of the objects on the right.] ...
... Stars go through a number of stages in the process of forming from an interstellar cloud: [You don’t have to memorize these numbers, but they do tell an important story, and you should understand the names of the objects on the right.] ...
Stars
... the outer layers. Since interior material is likely to have undergone nuclear reactions, which change the elemental abundances, this mixing affects the abundances in the star's atmosphere. These can be observed by studying stellar spectra. They may also be ejected from the star in a stellar wind, an ...
... the outer layers. Since interior material is likely to have undergone nuclear reactions, which change the elemental abundances, this mixing affects the abundances in the star's atmosphere. These can be observed by studying stellar spectra. They may also be ejected from the star in a stellar wind, an ...
Astronomy Webquest _2 STARS
... compressed ________________________________________ material, and are so dense that their mass is comparable to that of the Sun, even though their size is similar to that of the Earth's. A matchbox of white dwarf material would weigh the same as fifteen elephants. Newly created white dwarfs have som ...
... compressed ________________________________________ material, and are so dense that their mass is comparable to that of the Sun, even though their size is similar to that of the Earth's. A matchbox of white dwarf material would weigh the same as fifteen elephants. Newly created white dwarfs have som ...
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.