Supermassive black holes
... 1) They are generally very distant 2) They were more common early in time 3) Galaxy collisions might turn them on 4)Nearby galaxies might hold dead quasars ...
... 1) They are generally very distant 2) They were more common early in time 3) Galaxy collisions might turn them on 4)Nearby galaxies might hold dead quasars ...
Sample Exam 3
... B) stars existed out to such large distances that the Universe must be infinite. C) the Sun was on the outer edge of a giant spiral nebula. D) other stars orbit the Sun but look faint because they are in the outer part of the Solar System. 6) Recent observations indicate that the Milky Way is orbite ...
... B) stars existed out to such large distances that the Universe must be infinite. C) the Sun was on the outer edge of a giant spiral nebula. D) other stars orbit the Sun but look faint because they are in the outer part of the Solar System. 6) Recent observations indicate that the Milky Way is orbite ...
Astronomy 102, Spring 2003 Solutions to Review Problems
... other. (It’s a different matter in the cores of globular clusters, and even right at the center of our galaxy, but consider the Solar neighborhood for now.) Thus, if there is a binary star system, almost certainly the stars formed together, as it is very unlikely that they would have come across eac ...
... other. (It’s a different matter in the cores of globular clusters, and even right at the center of our galaxy, but consider the Solar neighborhood for now.) Thus, if there is a binary star system, almost certainly the stars formed together, as it is very unlikely that they would have come across eac ...
Lecture 10: The Milky Way
... This gives us the absolute luminosities of low-mass stars, and using binary systems we can calibrate our models to true masses and radii (see earlier). The trouble is that within 100pc we have no massive stars and only 4 giants – how do we calibrate these? To get distances to objects further away we ...
... This gives us the absolute luminosities of low-mass stars, and using binary systems we can calibrate our models to true masses and radii (see earlier). The trouble is that within 100pc we have no massive stars and only 4 giants – how do we calibrate these? To get distances to objects further away we ...
Galaxy1
... than the Milky Way is producing stars. • Most of the erupted gas is coming from supernova explosions. This is star formation on steroids. • Why do you think this little galaxy is producing stars so rapidly? Think about the mechanisms for producing stars. ...
... than the Milky Way is producing stars. • Most of the erupted gas is coming from supernova explosions. This is star formation on steroids. • Why do you think this little galaxy is producing stars so rapidly? Think about the mechanisms for producing stars. ...
distance to the centre of the Milky Way.
... Long-exposure photographs show many more stars (fainter than just the eye + telescope can see). This yields better statistical results. ...
... Long-exposure photographs show many more stars (fainter than just the eye + telescope can see). This yields better statistical results. ...
The Marathon
... If everything is on schedule, it should be around 2:00 a.m. at this point. We'll now slowly move toward the summer time objects. Moving 15° south of M104 is the globular cluster M68 in Hydra. Following the path of Hydra's tail leads us to the magnitude 3.0 star Gamma Hydrae. Moving 6° to the south l ...
... If everything is on schedule, it should be around 2:00 a.m. at this point. We'll now slowly move toward the summer time objects. Moving 15° south of M104 is the globular cluster M68 in Hydra. Following the path of Hydra's tail leads us to the magnitude 3.0 star Gamma Hydrae. Moving 6° to the south l ...
ASTRONOMY 113 Laboratory Kepler`s 3rd Law and the Mass of Sgr A
... it all along: At the center of virtually every galaxy lives a super-massive black hole. We know this, because material around the black hole follows Keplerian orbits, which sometimes allows us to measure the mass of the black hole directly (like in the case of M87 and Sgr A*). While these black hole ...
... it all along: At the center of virtually every galaxy lives a super-massive black hole. We know this, because material around the black hole follows Keplerian orbits, which sometimes allows us to measure the mass of the black hole directly (like in the case of M87 and Sgr A*). While these black hole ...
Messier 87
Messier 87 (also known as Virgo A or NGC 4486, and generally abbreviated to M87) is a supergiant elliptical galaxy in the constellation Virgo. One of the most massive galaxies in the local universe, it is notable for its large population of globular clusters—M87 contains about 12,000 compared to the 150-200 orbiting the Milky Way—and its jet of energetic plasma that originates at the core and extends outward at least 1,500 parsecs (4,900 light-years), travelling at relativistic speed. It is one of the brightest radio sources in the sky, and is a popular target for both amateur astronomy observations and professional astronomy study.French astronomer Charles Messier discovered M87 in 1781, cataloguing it as a nebulous feature while searching for objects that would confuse comet hunters. The second brightest galaxy within the northern Virgo Cluster, M87 is located about 16.4 million parsecs (53.5 million light-years) from Earth. Unlike a disk-shaped spiral galaxy, M87 has no distinctive dust lanes. Instead, it has an almost featureless, ellipsoidal shape typical of most giant elliptical galaxies, diminishing in luminosity with distance from the centre. Forming around one sixth of M87's mass, the stars in this galaxy have a nearly spherically symmetric distribution, their density decreasing with increasing distance from the core. At the core is a supermassive black hole, which forms the primary component of an active galactic nucleus. This object is a strong source of multiwavelength radiation, particularly radio waves. M87's galactic envelope extends out to a radius of about 150 kiloparsecs (490,000 light-years), where it has been truncated—possibly by an encounter with another galaxy. Between the stars is a diffuse interstellar medium of gas that has been chemically enriched by elements emitted from evolved stars.