Black holes can have a mass anywhere from a few solar masses (for stellar black holes), to about 20 billion solar masses (for the largest known supermassive black holes, in the centers of galaxies). The radius of a black hole (more precisely, of its event horizon) is directly proportional to its mass; a black hole with the mass of the Sun would have a radius of about 3 km, one that has a million times the mass of the Sun would have a radius a million times as much, etc.
Calculations indicate the supermassive black hole at the center of the Andromeda Galaxy is roughly one to two hundred million solar masses. By comparison, our Milky Way galaxy's own supermassive is just over four million times the mass of our Sun. For a sense of scale, if the Milky Way's black hole was placed where the Sun is, its size would make it a little under a quarter of the orbit of Mercury. By comparison, if Andromeda's supermassive black hole was put where our Sun is, its outer edge would reach somewhere between the vicinity of the orbit of Jupiter almost out to Saturn's.
Nope.. Light always travels at the same speed. However, black holes do affect the trajectory of the photons, hense diverting the direction of the light.
There are hypotheses about so called 'virtual particles' that may travel faster than speed of light, and hence are not sucked up by Black Holes. Also, Black Holes cannot suck another bigger Black Hole, when they meet a bigger one, they get sucked up rather.
By observing the rotation, and calculating the diameter. If you know the diameter of the galaxy, a certain rotation speed implies a certain mass (to be stable at that speed). It turns out there is 5-10 times more mass than the known masses. Read about "dark mass" for more details.By observing the rotation, and calculating the diameter. If you know the diameter of the galaxy, a certain rotation speed implies a certain mass (to be stable at that speed). It turns out there is 5-10 times more mass than the known masses. Read about "dark mass" for more details.By observing the rotation, and calculating the diameter. If you know the diameter of the galaxy, a certain rotation speed implies a certain mass (to be stable at that speed). It turns out there is 5-10 times more mass than the known masses. Read about "dark mass" for more details.By observing the rotation, and calculating the diameter. If you know the diameter of the galaxy, a certain rotation speed implies a certain mass (to be stable at that speed). It turns out there is 5-10 times more mass than the known masses. Read about "dark mass" for more details.
Earth's rotation speed is gradually decreasing, as a result of the tides.
The speed of rotation is greatest at the equator; 1038 miles per hour.
as high as 98.7% of the speed of light
The speed of rotation of a galaxy is related to the mass of the galaxy. Most galaxies appear to be spinning more quickly than their masses could account for, leading some scientists to believe that (many? most?) galaxies are heavier than they appear to be. So if there is a lot of extra mass that we cannot see, a black hole is a logical supposition. We can't prove it - yet - but many astronomers believe that supermassive black holes may reside in the centers of most galaxies.
Nope.. Light always travels at the same speed. However, black holes do affect the trajectory of the photons, hense diverting the direction of the light.
Obstructions, black holes, etc.
A black hole has an escape velocity of the speed of light, at least theoretically. Oddly, though, each galaxy has a black hole and we can detect them because they throw off massive amounts of energy. If the escape velocity is greater than the speed of light, then no light or energy of any kind should escape. So black holes are not quite the perfect consumers of everything.
Everything is moving away from everything else at the same speed, so black holes moving is relative to where you are.
No. The escape velocity of a black hole is greater than the speed of light.
Scientists believe that a great may of the galaxies of all types may have black holes in their centers. One of the reasons is that most things in space, including most galaxies, rotate. (If they were standing still, their mutual gravitational attraction would drag them into each other.) We can sometimes measure the speed of the rotation, and calculate how much mass the galaxy must have in order to hold itself together - because rotation tends to pull things apart. For most galaxies, we can't see enough mass to hold them together. Gravity is the "glue" that keeps spinning things together, and gravity comes from mass. So the only thing that holds those spinning galaxies together would be "invisible" mass. Some scientists have theorized about "dark matter", adding mass but being invisible. Black holes also add mass, and aren't visible, and are the simpler explanation.
The source of its gravity is its mass. Black holes also have the property of being very dense. Black holes by definition are objects where the escape velocity is equal to or greater than the speed of light.
There are hypotheses about so called 'virtual particles' that may travel faster than speed of light, and hence are not sucked up by Black Holes. Also, Black Holes cannot suck another bigger Black Hole, when they meet a bigger one, they get sucked up rather.
By observing the rotation, and calculating the diameter. If you know the diameter of the galaxy, a certain rotation speed implies a certain mass (to be stable at that speed). It turns out there is 5-10 times more mass than the known masses. Read about "dark mass" for more details.By observing the rotation, and calculating the diameter. If you know the diameter of the galaxy, a certain rotation speed implies a certain mass (to be stable at that speed). It turns out there is 5-10 times more mass than the known masses. Read about "dark mass" for more details.By observing the rotation, and calculating the diameter. If you know the diameter of the galaxy, a certain rotation speed implies a certain mass (to be stable at that speed). It turns out there is 5-10 times more mass than the known masses. Read about "dark mass" for more details.By observing the rotation, and calculating the diameter. If you know the diameter of the galaxy, a certain rotation speed implies a certain mass (to be stable at that speed). It turns out there is 5-10 times more mass than the known masses. Read about "dark mass" for more details.
The earth's orbital speed has no influence or effect on its rotation.