Practice Exam for 3 rd Astronomy Exam
... under the gravity of its own mass and the process of star formation begins. The GMC will collapse and fragment around the very many dense cores in its interior. An empirical Monte Carlo simulation of this process of collapse predicts the size distribution of cloud fragments called the Birth Function ...
... under the gravity of its own mass and the process of star formation begins. The GMC will collapse and fragment around the very many dense cores in its interior. An empirical Monte Carlo simulation of this process of collapse predicts the size distribution of cloud fragments called the Birth Function ...
PDF only - at www.arxiv.org.
... column is 2.5(+2.5,-‐1.2)x1015 cm-‐2 ; results from UV absorption line measurements range between 0.6-‐2.1x1015 cm-‐2 (13), indicating that at least 10% of the CO along this line-‐of-‐sight ...
... column is 2.5(+2.5,-‐1.2)x1015 cm-‐2 ; results from UV absorption line measurements range between 0.6-‐2.1x1015 cm-‐2 (13), indicating that at least 10% of the CO along this line-‐of-‐sight ...
ASTR 1020 Homework Solutions Chapter 1
... 27. λmax = (0.0029 m •K) / (106 K) = 2.9 × 10 m = 2.9 nm, which is X-ray radiation. 29. The energy flux is proportional to the 4th power of the temperature. Alpha Lupus’s temperature (21,600 K) is greater than the Sun’s (5800 K) by a factor of 21,600 / 5800 = 3.72. The flux from Alpha Lupus’s surfac ...
... 27. λmax = (0.0029 m •K) / (106 K) = 2.9 × 10 m = 2.9 nm, which is X-ray radiation. 29. The energy flux is proportional to the 4th power of the temperature. Alpha Lupus’s temperature (21,600 K) is greater than the Sun’s (5800 K) by a factor of 21,600 / 5800 = 3.72. The flux from Alpha Lupus’s surfac ...
Line-profile tomography of exoplanet transits – II. A gas
... exoplanet hosts to solar- and later-type, sharp-lined stars. Here we extend the realm of stars with known planetary companions to include hot, fast-rotating stars. Planet-like transits have previously been reported in the lightcurve obtained by the SuperWASP survey of the A5 star HD15082 (WASP-33; V ...
... exoplanet hosts to solar- and later-type, sharp-lined stars. Here we extend the realm of stars with known planetary companions to include hot, fast-rotating stars. Planet-like transits have previously been reported in the lightcurve obtained by the SuperWASP survey of the A5 star HD15082 (WASP-33; V ...
GG_CERN_0707
... Cored mass profiles, with similar mean mass densities ~0.1M/pc3, ~5GeV/cc An apparent characteristic (minimum) mass dark ...
... Cored mass profiles, with similar mean mass densities ~0.1M/pc3, ~5GeV/cc An apparent characteristic (minimum) mass dark ...
Name - CLC Charter School
... When the supernova is done exploding, as an effect of the large transfer of matter and energy, there is a very different kind of star left. This star is called a spinning neutron star. Neutron stars produce radio waves in a steady stream or in random bursts. But if a star is massive enough, it can l ...
... When the supernova is done exploding, as an effect of the large transfer of matter and energy, there is a very different kind of star left. This star is called a spinning neutron star. Neutron stars produce radio waves in a steady stream or in random bursts. But if a star is massive enough, it can l ...
Towards Gravitational Wave Astronomy
... to the field equations demonstrating that weakly self-gravitating objects, when boosted toward each other with large velocities so that the net mass of the space time (in the center of mass frame) is dominated by the kinetic energy, generically form a black hole when the interaction occurs within a ...
... to the field equations demonstrating that weakly self-gravitating objects, when boosted toward each other with large velocities so that the net mass of the space time (in the center of mass frame) is dominated by the kinetic energy, generically form a black hole when the interaction occurs within a ...
X-ray and UV Transients
... >10 events y-1 even if the sensitivity is 102 less. • The observed signals have UV flux~host, so confusion with (even mildly) variable sources is an issue unless additional information is available • A combined UV survey+optical SN survey like PTF will be powerful to get retrospective measurements ...
... >10 events y-1 even if the sensitivity is 102 less. • The observed signals have UV flux~host, so confusion with (even mildly) variable sources is an issue unless additional information is available • A combined UV survey+optical SN survey like PTF will be powerful to get retrospective measurements ...
THE INNER CORE OF A NEUTRON STAR Part 1
... Abstract: Neutron stars are formed by super compaction that result from the gravitational collapse of a massive star after a supernova. Neutron star composition makes it so heavy that its density is at least twice the mass of Earth’s Sun. Current thinking subscribes to the possibility that a neutron ...
... Abstract: Neutron stars are formed by super compaction that result from the gravitational collapse of a massive star after a supernova. Neutron star composition makes it so heavy that its density is at least twice the mass of Earth’s Sun. Current thinking subscribes to the possibility that a neutron ...
Presentazione di PowerPoint
... same sense in any normal disk having angular speed Ω decreasing outward. Both types of motion occur in a direction opposite to Ω itself It is precisely this agreement that makes it possible for a wide-open pattern of epiciclic vibrations to resonate with the shear flow. The only extra-need is for st ...
... same sense in any normal disk having angular speed Ω decreasing outward. Both types of motion occur in a direction opposite to Ω itself It is precisely this agreement that makes it possible for a wide-open pattern of epiciclic vibrations to resonate with the shear flow. The only extra-need is for st ...
Transcript - Chandra X
... are more diverse and complicated than this diagram would lead you to believe. For instance, there are many more stellar classes than OBAFGKM; however for simplicity’s sake, only the classes that contain a large majority are shown. Absolute magnitude – the intrinsic brightness of stars – is similar ...
... are more diverse and complicated than this diagram would lead you to believe. For instance, there are many more stellar classes than OBAFGKM; however for simplicity’s sake, only the classes that contain a large majority are shown. Absolute magnitude – the intrinsic brightness of stars – is similar ...
Stars
... The brightest star in the sky (besides the Sun) is Sirius. It is 2.6 pc from Earth. How long does it take light from Sirius to reach us? ...
... The brightest star in the sky (besides the Sun) is Sirius. It is 2.6 pc from Earth. How long does it take light from Sirius to reach us? ...
white dwarfs, neutron stars, black hole
... energy from fusion pours out from the core, setting up an outward pressure in the gas around it that balances the inward pull of gravity. When the released energy reaches the outer layers of the ball of gas and dust, it moves off into space in the form of electromagnetic radiation. The ball, now a s ...
... energy from fusion pours out from the core, setting up an outward pressure in the gas around it that balances the inward pull of gravity. When the released energy reaches the outer layers of the ball of gas and dust, it moves off into space in the form of electromagnetic radiation. The ball, now a s ...
64 Exercise Solutions_e
... Options A and C are incorrect. Since the stars have the same luminosity, Q must be farther away so that it looks fainter. By , the intensity is inversely proportional to the distance squared. Therefore, Q’s distance should be 5 times that of P such that its brightness is 1/52 = 1/25 that of P. ...
... Options A and C are incorrect. Since the stars have the same luminosity, Q must be farther away so that it looks fainter. By , the intensity is inversely proportional to the distance squared. Therefore, Q’s distance should be 5 times that of P such that its brightness is 1/52 = 1/25 that of P. ...
Tutorial: Luminosity
... However, the “brightness” of a star decreases as one moves farther and farther away. If a sphere of radius d is drawn around the star, it should be clear that the energy/sec through the surface of this sphere is the same as the energy/sec emitted through the surface of the star, since there is no me ...
... However, the “brightness” of a star decreases as one moves farther and farther away. If a sphere of radius d is drawn around the star, it should be clear that the energy/sec through the surface of this sphere is the same as the energy/sec emitted through the surface of the star, since there is no me ...
Lesson 5 - Standards Solution
... part, circle the correct answer in the left column. In the right column, explain why each option is either right or wrong. There is only one right answer for each part. from “Black Holes” by NASA.gov Black holes can be big or small. Scientists think the smallest black holes are as small as just one ...
... part, circle the correct answer in the left column. In the right column, explain why each option is either right or wrong. There is only one right answer for each part. from “Black Holes” by NASA.gov Black holes can be big or small. Scientists think the smallest black holes are as small as just one ...
Cygnus X-1
Cygnus X-1 (abbreviated Cyg X-1) is a well-known galactic X-ray source, thought to be a black hole, in the constellation Cygnus. It was discovered in 1964 during a rocket flight and is one of the strongest X-ray sources seen from Earth, producing a peak X-ray flux density of 6977229999999999999♠2.3×10−23 Wm−2 Hz−1 (7003230000000000000♠2.3×103 Jansky). Cygnus X-1 was the first X-ray source widely accepted to be a black hole and it remains among the most studied astronomical objects in its class. The compact object is now estimated to have a mass about 14.8 times the mass of the Sun and has been shown to be too small to be any known kind of normal star, or other likely object besides a black hole. If so, the radius of its event horizon is about 7004440000000000000♠44 km.Cygnus X-1 belongs to a high-mass X-ray binary system about 7019574266339685654♠6070 ly from the Sun that includes a blue supergiant variable star designated HDE 226868 which it orbits at about 0.2 AU, or 20% of the distance from the Earth to the Sun. A stellar wind from the star provides material for an accretion disk around the X-ray source. Matter in the inner disk is heated to millions of degrees, generating the observed X-rays. A pair of jets, arranged perpendicular to the disk, are carrying part of the energy of the infalling material away into interstellar space.This system may belong to a stellar association called Cygnus OB3, which would mean that Cygnus X-1 is about five million years old and formed from a progenitor star that had more than 7001400000000000000♠40 solar masses. The majority of the star's mass was shed, most likely as a stellar wind. If this star had then exploded as a supernova, the resulting force would most likely have ejected the remnant from the system. Hence the star may have instead collapsed directly into a black hole.Cygnus X-1 was the subject of a friendly scientific wager between physicists Stephen Hawking and Kip Thorne in 1975, with Hawking betting that it was not a black hole. He conceded the bet in 1990 after observational data had strengthened the case that there was indeed a black hole in the system. This hypothesis has not been confirmed due to a lack of direct observation but has generally been accepted from indirect evidence.