Celestial Distances
... In contrast, most stars are constant in their luminosity (at least within a percent or two) ...
... In contrast, most stars are constant in their luminosity (at least within a percent or two) ...
The Sky Viewed from Earth - Beck-Shop
... 3 Do all civilizations recognize the same constellations? Today, we have no problem knowing what day and month it is. We have calendars, watches, newspapers, television, computers, and Internet to keep us informed. But what about 4000 years ago? Back then, there was only the sky . . . Knowing one’s ...
... 3 Do all civilizations recognize the same constellations? Today, we have no problem knowing what day and month it is. We have calendars, watches, newspapers, television, computers, and Internet to keep us informed. But what about 4000 years ago? Back then, there was only the sky . . . Knowing one’s ...
Time From the Perspective of a Particle Physicist
... S. Chandrashekar 1910-1995 worked out in 1930 on boat from India to England prior to grad school. Later became professor at Chicago. Nobel prize 1983 ...
... S. Chandrashekar 1910-1995 worked out in 1930 on boat from India to England prior to grad school. Later became professor at Chicago. Nobel prize 1983 ...
New Worlds on the Horizon: Earth-Sized Planets Close to Other
... or “jitter” produced by turbulence, spots, and acoustic oscillations in stellar atmospheres. Better sensitivity may eventually be achieved by understanding the precise characteristics of such noise, or averaging over many orbits. Meanwhile, meter-per-second accuracy is not sufficient to find a “twi ...
... or “jitter” produced by turbulence, spots, and acoustic oscillations in stellar atmospheres. Better sensitivity may eventually be achieved by understanding the precise characteristics of such noise, or averaging over many orbits. Meanwhile, meter-per-second accuracy is not sufficient to find a “twi ...
Problem Set No. 5
... While a 0.4 M⊙ star may burn a larger fraction of its hydrogen, we do not think it would burn it all before leaving the main sequence. If, however, it were fully mixed, it would burn all its hydrogen and could thus live much longer than our 100 billion yr estimate. ...
... While a 0.4 M⊙ star may burn a larger fraction of its hydrogen, we do not think it would burn it all before leaving the main sequence. If, however, it were fully mixed, it would burn all its hydrogen and could thus live much longer than our 100 billion yr estimate. ...
Communication with Extraterrestrial Intelligence (CETI)
... reconsider our own solar system (where we may have some hope of systematic in situ sampling), and we should expand our inspection to any bodies capable of providing raw materials and energy sources that might be exploited by biology of any sort. Thus, in addition to the terrestrial planets Venus, Ma ...
... reconsider our own solar system (where we may have some hope of systematic in situ sampling), and we should expand our inspection to any bodies capable of providing raw materials and energy sources that might be exploited by biology of any sort. Thus, in addition to the terrestrial planets Venus, Ma ...
Geo-centric astronomy from Pythagoras to Ptolemy File
... Stars move in a regular pattern, which repeats every 24 hrs. For example, suppose you live in Northern hemisphere, and you go out at 9 pm for some stargazing. Suppose you focus on the cluster of seven stars we call saptarishi in India or the Big Dipper in the West. During the night, you will see the ...
... Stars move in a regular pattern, which repeats every 24 hrs. For example, suppose you live in Northern hemisphere, and you go out at 9 pm for some stargazing. Suppose you focus on the cluster of seven stars we call saptarishi in India or the Big Dipper in the West. During the night, you will see the ...
In the beginning… Astronomical Observations of Star Formation
... well. These include the alkalis (Na, K, Rb, Cs) and elements such as sulfur, lead, and indium. Planetesimal accretion took place before these elements could condense. Final assembly of the terrestrial planets took longer and was not complete until gas had cleared from inner solar system. ...
... well. These include the alkalis (Na, K, Rb, Cs) and elements such as sulfur, lead, and indium. Planetesimal accretion took place before these elements could condense. Final assembly of the terrestrial planets took longer and was not complete until gas had cleared from inner solar system. ...
English Summary
... is called radiation and gives the star a colour. The colour of a star is related to its temperature. For instance, Rigel in the constellation Orion is very blue (and hot) while Betelgeuse is red (and cool). This concept is easier if we think of a wire that is being heated up. As it gets hotter (radi ...
... is called radiation and gives the star a colour. The colour of a star is related to its temperature. For instance, Rigel in the constellation Orion is very blue (and hot) while Betelgeuse is red (and cool). This concept is easier if we think of a wire that is being heated up. As it gets hotter (radi ...
Multiple Choice, continued
... • After the supergiant stage, the star collapses, producing such high temperatures that nuclear fusion begins again. This time, carbon atoms in the core fuse into heavier elements until the core is almost entirely made of iron. • When nuclear fusion stops, the star’s core begins to collapse under it ...
... • After the supergiant stage, the star collapses, producing such high temperatures that nuclear fusion begins again. This time, carbon atoms in the core fuse into heavier elements until the core is almost entirely made of iron. • When nuclear fusion stops, the star’s core begins to collapse under it ...
File
... • After the supergiant stage, the star collapses, producing such high temperatures that nuclear fusion begins again. This time, carbon atoms in the core fuse into heavier elements until the core is almost entirely made of iron. • When nuclear fusion stops, the star’s core begins to collapse under it ...
... • After the supergiant stage, the star collapses, producing such high temperatures that nuclear fusion begins again. This time, carbon atoms in the core fuse into heavier elements until the core is almost entirely made of iron. • When nuclear fusion stops, the star’s core begins to collapse under it ...
Document
... Still heats up: surface = 4000 K Core temp = 5,000,000 K Violent surface activity creates strong winds that blow material away near the protostar’s surface. • Clear away the dust and gas between planets. ...
... Still heats up: surface = 4000 K Core temp = 5,000,000 K Violent surface activity creates strong winds that blow material away near the protostar’s surface. • Clear away the dust and gas between planets. ...
2.4 Statistical properties of radial velocity planets
... – for about 1 % of the stars a close in (<0.1 AU), hot Jupiter with mP sin i > 0.1MJ is detected, – for about 15 % of the stars a giant planet with mP sin i > 0.1MJ out to a separation of 5 AU is present, – RV-surveys can not say much about the frequency of giant planets at large separation > 5 AU, ...
... – for about 1 % of the stars a close in (<0.1 AU), hot Jupiter with mP sin i > 0.1MJ is detected, – for about 15 % of the stars a giant planet with mP sin i > 0.1MJ out to a separation of 5 AU is present, – RV-surveys can not say much about the frequency of giant planets at large separation > 5 AU, ...
Chapter 26 ~ Stars and Galaxies Section 1 ~ Constellations
... A spectroscope helps us find out what stars are made of. It disperses, or separates, white light from a star into a very wide spectrum of colors — much wider than a normal prism does. When spread very wide, black lines appear in the spectrum. The first scientists to observe these lines wondered why ...
... A spectroscope helps us find out what stars are made of. It disperses, or separates, white light from a star into a very wide spectrum of colors — much wider than a normal prism does. When spread very wide, black lines appear in the spectrum. The first scientists to observe these lines wondered why ...
Luminosity
... These two stars have about the same luminosity— which one appears brighter? A. Alpha Centauri B. The Sun ...
... These two stars have about the same luminosity— which one appears brighter? A. Alpha Centauri B. The Sun ...
Star Formation
... • Supernova blast waves near clouds can initiate star formation (happened for our own sun, from SNe produced radioactive daughter products in meteorites) • Collapse raises density, core cannot radiate away heat gravitational collapse heat fast enough, and temp rises, until H fusion begins at 10 mill ...
... • Supernova blast waves near clouds can initiate star formation (happened for our own sun, from SNe produced radioactive daughter products in meteorites) • Collapse raises density, core cannot radiate away heat gravitational collapse heat fast enough, and temp rises, until H fusion begins at 10 mill ...