Black Holes? Need Help.?

Question

How do the existence of quasars and pulsars encourage physicists that black holes really exist?

Answer 1

Quazars are essentialy very large black holes that are feeding.

They have very high red-shift which indicates they must be very far away. Dispite that all known ones are extraordinarily far away, they can be observed with amature telescopes. This indicates that they are the brightest objects in the universe, except the short-lived supernovae.

Currently, there is no other why to explain how any object could be that bright for that long. They may not be Black Holes, but according to everything we know today, we can't imagine how.

Answer 2

There is one fatal,simple difference between a normal celestial body,a star,a planet.a neutron star and a black hole.
Stars planets and black holes,when viewed from above the surface,all feature a mass and gravitational field that is concentrated at the center.
If you venture below the surface of anything but a black hole,the mass and gravity is not focused at the center due to the mass and gravity that separates you from the surface.
Each has a surface orbital velocity[The earth 25,000 mph. a black hole the speed of light]
If you could venture below the event horizon of a black hole,the mass and gravity would still be focused at the center.
The subsurface orbital velocity would be greater than the speed of light.
To have a black hole you need some way to become superluminal which is not possible!

Answer 3

A black hole accrues when a star collapses and sends out massive amount of gamma rays. Then sucks all the massive energy back in. All stars are suns they are billions of light years away. Mind you a light year is 5.9 trillion miles. If there were other people out there our sun would be a star to them. They have recently found out their are moving black holes that would suck everything up including earth however they are billions of light years away and nothing to worry about for the next millions of years.History channel is showing this some time this week.

Answer 4

in astronomy, celestial object of such extremely intense gravity that it attracts everything near it and in some instances prevents everything, including light, from escaping. The term was first used in reference to a star in the last phases of gravitational collapse (the final stage in the life history of certain stars; see stellar evolution) by the American physicist John A. Wheeler.

Gravitational collapse begins when a star has depleted its steady sources of nuclear energy and can no longer produce the expansive force, a result of normal gas pressure, that supports the star against the compressive force of its own gravitation. As the star shrinks in size (and increases in density), it may assume one of several forms depending upon its mass. A less massive star may become a white dwarf, while a more massive one would become a supernova. If the mass is less than three times that of the sun, it will then form a neutron star. However, if the final mass of the remaining stellar core is more than three solar masses, as shown by the American physicists J. Robert Oppenheimer and Hartland S. Snyder in 1939, nothing remains to prevent the star from collapsing without limit to an indefinitely small size and infinitely large density, a point called the "singularity."

At the point of singularity the effects of Einstein's general theory of relativity become paramount. According to this theory, space becomes curved in the vicinity of matter; the greater the concentration of matter, the greater the curvature. When the star (or supernova remnant) shrinks below a certain size determined by its mass, the extreme curvature of space seals off contact with the outside world. The place beyond which no radiation can escape is called the event horizon, and its radius is called the Schwarzschild radius after the German astronomer Karl Schwarzschild, who in 1916 postulated the existence of collapsed celestial objects that emit no radiation. For a star with a mass equal to that of the sun, this limit is a radius of only 1.86 mi (3.0 km). Even light cannot escape a black hole, but is turned back by the enormous pull of gravitation.

It is now believed that the origin of some black holes is nonstellar. Some astrophysicists suggest that immense volumes of interstellar matter can collect and collapse into supermassive black holes, such as are found at the center of some galaxies. The British physicist Stephen Hawking has postulated still another kind of nonstellar black hole. Called a primordial, or mini, black hole, it would have been created during the "big bang," in which the universe was created (see cosmology). Unlike stellar black holes, primordial black holes create and emit elementary particles, called Hawking radiation, until they exhaust their energy and expire. It has also been suggested that the formation of black holes may be associated with intense gamma ray bursts. Beginning with a giant star collapsing on itself or the collision of two neutron stars, waves of radiation and subatomic particles are propelled outward from the nascent black hole and collide with one another, releasing the gamma radiation. Also released is longer-lasting electromagnetic radiation in the form of X rays, radio waves, and visible wavelengths that can be used to pinpoint the location of the disturbance.

Because light and other forms of energy and matter are permanently trapped inside a black hole, it can never be observed directly. However, a black hole can be detected by the effect of its gravitational field on nearby objects (e.g., if it is orbited by a visible star), during the collapse while it was forming, or by the X rays and radio frequency signals emitted by rapidly swirling matter being pulled into the black hole. A small number of possible black holes have been detected. The first discovered (1971) was Cygnus X-1, an X-ray source in the constellation Cygnus. In 1994 astronomers employing the Hubble Space Telescope announced that they had found conclusive evidence of a supermassive black hole in the M87 galaxy in the constellation Virgo. The first evidence (2002) of a binary black hole, two supermassive black holes circling one another, was detected in images from the orbiting Chandra X-ray Observatory. Located in the galaxy NGC6240, the pair are 3,000 light years apart, travel around each other at a speed of about 22,000 mph (35,415 km/hr), and have the mass of 100 million suns each. As the distance between them shrinks over 100 million years, the circling speed will increase until it approaches the speed of light, about 671 million mph (1080 million km/hr). The black holes will then collide spectacularly, spewing radiation and gravitational waves across the universe.