are any black holes close to earth?
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After HR 6819's black hole, the nearest known black hole is about 3,000 light-years away from Earth in the constellation Monoceros. But there could still be others lurking even closer that have yet to be detected; astronomers estimate that there are millions of black holes in our galaxy alone.
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Neutron stars are city-size stellar objects with a mass about 1.4 times that of the sun. If the mass of the star collapsing is much more then it would form a black hole. ... Large black holes have a density less than that of a neutron star. So they do not need to contain a singularity (only e.g., neutron stars).
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Black-holes count as ordinary matter (made from 16 particles of standard model). As you know, ordinary matter and energy can be converted to each other (they are actually the same thing) and they make about 4.9% of the known universe.
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Proxima Centauri, the nearest star, is 268,000 au away. The nearest bright star, Sirius, is 505,929 au away. The Moon orbits the Earth. ... The nearest star, the Sun, is still a mind-bogglingly large distance, but it's saner and far closer than the stars of other solar systems.
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Black holes provide an important tool for probing and testing the fundamental laws of the universe. All objects exert an attractive gravitational force which depends on their mass.
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11 billion of these estimated planets may be orbiting Sun-like stars. The nearest such planet may be 12 light-years away, according to the scientists. As of March 2020, a total of 55 potentially habitable exoplanets have been found.
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The Moon orbits the Earth. The stars are so incredibly far away that the distance to them is incomprehensible to the human mind in comparison to any sane other distance. The nearest star, the Sun, is still a mind-bogglingly large distance, but it's saner and far closer than the stars of other solar systems.
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The defining feature of a black hole is the appearance of an event horizon—a boundary in spacetime through which matter and light can pass only inward towards the mass of the black hole. Nothing, not even light, can escape from inside the event horizon.
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The closest star to Earth are three stars in the Alpha Centauri system. The two main stars are Alpha Centauri A and Alpha Centauri B, which form a binary pair. They are an average of 4.3 light-years from Earth.
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In space no one can hear you explode… Many astronomical objects such as novae, supernovae and black hole mergers are known to catastrophically 'explode'. ... But as long as the explosion doesn't require oxygen, then it will work in much the same way in space as on Earth.
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It is about 4.22 light-years from Earth and is the closest star other than the sun. Alpha Centauri A and B orbit a common center of gravity every 80 years. The average distance between them is about 23 astronomical units (AU) — a little more than the distance between the sun and Uranus.
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No such micro black hole has been observed at CERN. In September 2010, a signal that is closely related to black hole Hawking radiation (see Analog models of gravity) was claimed to have been observed in a laboratory experiment involving optical light pulses. However, the results remain unverified and debatable.
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The 'event horizon' is the boundary defining the region of space around a black hole from which nothing (not even light) can escape. In other words, the escape velocity for an object within the event horizon exceeds the speed of light. ... In theory, any mass can be compressed sufficiently to form a black hole.
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Wormholes contain two mouths, with a throat connecting the two. ... Certain solutions of general relativity allow for the existence of wormholes where the mouth of each is a black hole. However, a naturally occurring black hole, formed by the collapse of a dying star, does not by itself create a wormhole.
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Yes, indeed! Many nebulae are visible from Earth in a small and cheap telescope, and even to the naked eye (if you are standing in a sufficiently dark place).
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A team of scientists from the University of Geneva has confirmed the existence of an Earth-sized planet orbiting the star closest to the sun. The planet, called Proxima b, is 1.17 times the mass of Earth and is located in the habitable zone of Promixa Centauri, 4.2 light years away.
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It is possible that this Universe is the inside of black holes in a container Universe. ... All coming energy is converting to the mass, increasing gravity force near black hole. Coming matter (atoms) are crippled and they are destroyed for thousand miles radius. So, there is no atoms not only in black hole but even near.