The figure below shows what scientists over 1000 years ago thought
... Give one way that the historical model of the solar system shown in the figure above is different from what we now know about the solar system. ...
... Give one way that the historical model of the solar system shown in the figure above is different from what we now know about the solar system. ...
observation reports
... After a miserable night of Perseid maximum the previous night (only one meteor seen in a murky near-overcast sky), I had some more luck this time. This was a casual diversion in between revisiting deep-sky objects, the showpieces being M11, M13 and the Double Cluster in Perseus. PERSEID WATCH 21:10 ...
... After a miserable night of Perseid maximum the previous night (only one meteor seen in a murky near-overcast sky), I had some more luck this time. This was a casual diversion in between revisiting deep-sky objects, the showpieces being M11, M13 and the Double Cluster in Perseus. PERSEID WATCH 21:10 ...
Neutron stars - Institut de Physique Nucleaire de Lyon
... – estimate of the maximum binding energy of a neutron star; – difference between Mb and M; – “enormous gravitational red shifts” R.C.Tolman; J.R.Oppenheimer & G.M.Volkoff (Phys. Rev., 3.01. – 15.02.1939) – “TOV equation” (hydrostatic equilibrium of a spherically symmetric star). O.&V.: maximum mas ...
... – estimate of the maximum binding energy of a neutron star; – difference between Mb and M; – “enormous gravitational red shifts” R.C.Tolman; J.R.Oppenheimer & G.M.Volkoff (Phys. Rev., 3.01. – 15.02.1939) – “TOV equation” (hydrostatic equilibrium of a spherically symmetric star). O.&V.: maximum mas ...
ex-lup-v3
... •0.2 AU ring of emptiness around the star from the best models created using RADMC & RAYTRACE (Sipos et al. 2009) •Undergone a big outburst in 2008. Sipos et al. 2009. EX Lupi in quiescence. Astronomy & Astrophysics manuscrip no. exlup-quiescence. arXiv:0906.3168v1 ...
... •0.2 AU ring of emptiness around the star from the best models created using RADMC & RAYTRACE (Sipos et al. 2009) •Undergone a big outburst in 2008. Sipos et al. 2009. EX Lupi in quiescence. Astronomy & Astrophysics manuscrip no. exlup-quiescence. arXiv:0906.3168v1 ...
Type II Supernovae
... The trapping of neutrinos was confirmed because the timescale over which the neutrino burst appeared was about 10 seconds and the average detected neutrino energy was about 20 MeV. ...
... The trapping of neutrinos was confirmed because the timescale over which the neutrino burst appeared was about 10 seconds and the average detected neutrino energy was about 20 MeV. ...
Magnetic susceptibility, magnetization, magnetic moment and
... ones coming from the ChDSs. We investigate the fraction of ionizing radiation emitted in the star-forming region which is able to leak out the galaxy. The time- and direction-averaged escape fraction in our simulation is 0.35–0.4. Finally, we have calculated the total Hα luminosity of our model gala ...
... ones coming from the ChDSs. We investigate the fraction of ionizing radiation emitted in the star-forming region which is able to leak out the galaxy. The time- and direction-averaged escape fraction in our simulation is 0.35–0.4. Finally, we have calculated the total Hα luminosity of our model gala ...
CONSTELLATION CEPHEUS, KING OF ETHIOPIA Cepheus is a
... Cepheus is a constellation in the northern sky. It is named after Cepheus, King of Aethiopia in Greek mythology. He was deemed worthy of a place in the sky because he was fourth in descent from the nymph Io, one of the loves of Zeus – and having Zeus as a relative was always an advantage when it cam ...
... Cepheus is a constellation in the northern sky. It is named after Cepheus, King of Aethiopia in Greek mythology. He was deemed worthy of a place in the sky because he was fourth in descent from the nymph Io, one of the loves of Zeus – and having Zeus as a relative was always an advantage when it cam ...
samba2002v2
... spectroscopy, photometry and imaging, to study celestial sources. It can provide a general tool to explore the structure of compact sources and derive information on mass and angular momentum of supermassive objects. Comparing with the other three measurements, the development of X-ray polarimetry i ...
... spectroscopy, photometry and imaging, to study celestial sources. It can provide a general tool to explore the structure of compact sources and derive information on mass and angular momentum of supermassive objects. Comparing with the other three measurements, the development of X-ray polarimetry i ...
Astronomy 112: The Physics of Stars Class 15 Notes: Stars Before
... and thus it cannot be in hydrostatic equilibrium. Instead, Ugas ∝ P/ρ is too small compared to Ω. This means that the force of gravity compressing the cloud is stronger than the pressure force trying to hold it up. The cloud therefore collapses some. This further increases Ω, while leaving Ugas fixe ...
... and thus it cannot be in hydrostatic equilibrium. Instead, Ugas ∝ P/ρ is too small compared to Ω. This means that the force of gravity compressing the cloud is stronger than the pressure force trying to hold it up. The cloud therefore collapses some. This further increases Ω, while leaving Ugas fixe ...
Star formation and internal kinematics of irregular galaxies
... of parsecs and a couple of kiloparsecs. Thus a galaxy’s global structure and dynamics can be viewed as an organising framework, collecting up neutral gas and perhaps providing a trigger, after which a series of events leading to nuclear ignition proceeds under the control of forces largely independe ...
... of parsecs and a couple of kiloparsecs. Thus a galaxy’s global structure and dynamics can be viewed as an organising framework, collecting up neutral gas and perhaps providing a trigger, after which a series of events leading to nuclear ignition proceeds under the control of forces largely independe ...
Semiar PPT
... 4. Collisionless shocks, particle acceleration, magnetic field generation etc. poorly understood. ...
... 4. Collisionless shocks, particle acceleration, magnetic field generation etc. poorly understood. ...
Recent science results from VLTI commissioning
... • The role of stellar instabilities in the outer envelopes of single stars and/or of periodic tidal forcing by a companion and the formation of asymmetric ...
... • The role of stellar instabilities in the outer envelopes of single stars and/or of periodic tidal forcing by a companion and the formation of asymmetric ...
Young Stellar Objects in the Orion B Cloud
... of the mass function, is remarkably similar to the Orion Trapezium KLF, which has been reported to have a fraction of substellar objects of ~ 22 % (Muench et al. 2002). We conclude that the star formation environment in Orion B is similarly productive in forming substellar objects as are more massiv ...
... of the mass function, is remarkably similar to the Orion Trapezium KLF, which has been reported to have a fraction of substellar objects of ~ 22 % (Muench et al. 2002). We conclude that the star formation environment in Orion B is similarly productive in forming substellar objects as are more massiv ...
FIRST LIGHT IN THE UNIVERSE
... Input details depend on considerable imponderables: • TIGM 10,000 – 20,000 K ? ...
... Input details depend on considerable imponderables: • TIGM 10,000 – 20,000 K ? ...
Homologous Stellar Models and Polytropes Main Sequence Stars
... must still be on the Main Sequence, even if they are as old as the Universe. • Low-Mass Stars (0.7 6 M 6 2M ) in most cases end up losing most of their mass to become planetary nebulae before evolving on to the white dwarf cooling track. • Intermediate-Mass Stars (2 6 M 6 8M ) have evolution tracks ...
... must still be on the Main Sequence, even if they are as old as the Universe. • Low-Mass Stars (0.7 6 M 6 2M ) in most cases end up losing most of their mass to become planetary nebulae before evolving on to the white dwarf cooling track. • Intermediate-Mass Stars (2 6 M 6 8M ) have evolution tracks ...
Sharp Images of Galaxy Groups: Chandra and XMM Uncover New
... “Taffy galaxies” in X-rays? • Proposed by Condon et al. (1993) for UGC 12914/12915: radio bridge explained in terms of gas and magnetic fields from postcollision galaxies • Could NGC 741/742 constitute such a pair? Relative narrowness of bridge due to greater concentration of gas in ellipticals int ...
... “Taffy galaxies” in X-rays? • Proposed by Condon et al. (1993) for UGC 12914/12915: radio bridge explained in terms of gas and magnetic fields from postcollision galaxies • Could NGC 741/742 constitute such a pair? Relative narrowness of bridge due to greater concentration of gas in ellipticals int ...
PPT
... Outflow of the X-ray-emitting gas Evidence: – Low NH toward S diffuse emission – Short replenishment time of X-ray emitting gas – Pressure equilibrium between radio and X-ray emitting material ...
... Outflow of the X-ray-emitting gas Evidence: – Low NH toward S diffuse emission – Short replenishment time of X-ray emitting gas – Pressure equilibrium between radio and X-ray emitting material ...
File - Science Website
... them into a sensible order and use the correct scientific words. Explain briefly how stars like the Sun are thought to have been formed. ...
... them into a sensible order and use the correct scientific words. Explain briefly how stars like the Sun are thought to have been formed. ...
Widener University
... c) Calculate the Roche limit for a small frozen moon composed of water ice ( = 1000 kg/m3) near this ...
... c) Calculate the Roche limit for a small frozen moon composed of water ice ( = 1000 kg/m3) near this ...
Type I SuperNova
... The two might collide and form one star, which will collapse due to its mass and cause the carbon-detonation supernova. The carbon/oxygen fuse explosively, blowing the entire system into space and leaving nothing behind. ...
... The two might collide and form one star, which will collapse due to its mass and cause the carbon-detonation supernova. The carbon/oxygen fuse explosively, blowing the entire system into space and leaving nothing behind. ...
High-Mass Star Formation
... star forming cores Aspect ratios consistent with spherical symmetry Median size of 0.32 pc and median virial mass of 920 Msun Virial mass a factor of 2 to 3 larger than dust-determined mass Cumulative mass spectrum G ~ -0.9 similar to IMF of OB ...
... star forming cores Aspect ratios consistent with spherical symmetry Median size of 0.32 pc and median virial mass of 920 Msun Virial mass a factor of 2 to 3 larger than dust-determined mass Cumulative mass spectrum G ~ -0.9 similar to IMF of OB ...
HOW TO MAKE A SINGLETON sdB STAR VIA ACCELERATED STELLAR... Drew Clausen and Richard A. Wade
... completely removes its envelope before the merger. Furthermore, the total mass of the merged star must be in the range 0.53–0.84 M for the merged object to evolve into an sdB. We have computed a grid of models with η = 0.3 to make a preliminary exploration of the parameter space of progenitor syste ...
... completely removes its envelope before the merger. Furthermore, the total mass of the merged star must be in the range 0.53–0.84 M for the merged object to evolve into an sdB. We have computed a grid of models with η = 0.3 to make a preliminary exploration of the parameter space of progenitor syste ...
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.