What is the Great Attractor? It is the theorized gravitational center of our Milky Way Galaxy and 100,000 other galaxies. The universe is expanding at a rate of 2.2 million km per hour. All galaxies should therefore be moving at that speed, but it turns out we are not. Our Milky Way Galaxy is moving […]
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How long do black holes last? Black holes will slowly dissolve, but it will take far longer than the length of our universe, so it has never been observed. There are two ways that black holes form. The first way is when a star collapses. As stars die, they burn up all of their hydrogen,
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Is cryosleep possible? In theory, yes, but not for the length of time needed to travel anywhere decent in space. The idea behind cryosleep is to put astronauts into a state of suspended animation for the length of time it would take for them to reach wherever they are going. The advantages of this are
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How does an ion thruster work? It creates thrust by accelerating ions using electricity. An ion is a charged atom or molecule. Atoms always have an equal number of electrons and protons. Electrons have a negative charge and protons have a positive charge. Because there is an equal number of each, the charges balance themselves
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What was the last Apollo mission? The last Apollo mission was Apollo 17. The Apollo program stretched from 1967 until 1972. There was supposed to be an Apollo 18, 19, and 20 but they were all cancelled. The booster for Apollo 20 was repurposed to launch Skylab, America’s first space station into orbit. The decision
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Could Earth survive without the moon? The planet would survive, but the living organisms on it might have a harder time. The moon was probably formed when another protoplanet hit the young Earth, obliterating both and making the Earth and moon from the resultant mush. The moon began life at a distance of about 22,500
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How much space junk is there? There are over 128 million pieces of space junk in orbit around Earth at the moment. There are 5,465 satellites orbiting in space at the moment. 84% of those are in a low Earth orbit. There is also the International Space Station circling the Earth. Over the last decade,
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How can the inner core of the Earth switch rotation? Because it is separated from the solid mantle and can rotate at a different speed. The Earth has four layers. There is the outer crust that we and everything alive lives on. The crust is about 40 km deep and is only 1% of Earth’s
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How many dimensions are there? There are either 4, 10, 11, or infinite dimensions, depending on what theory you read. What is a dimension? A dimension is the minimum number of coordinates needed to specify a point within that dimension. We can experience four dimensions. The first dimension is length. A straight line exists in
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How did Galileo realize that the Earth orbits the sun? He realized it when he observed the orbit of Venus. Galileo was born in 1564 in Pisa, Italy. Galileo is famous for saying that the Earth orbits the sun rather than the sun orbits the Earth, but he was not the first person to come
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