Related topics: nasa · satellite · earth · solar system · spacecraft

NASA chief warns Congress about Chinese space station

NASA chief Jim Bridenstine told lawmakers Wednesday it was crucial for the US to maintain a presence in Earth's orbit after the International Space Station is decommissioned so that China does not gain a strategic advantage.

ISS moves to avoid space debris

Astronauts on the International Space Station carried out an "avoidance maneuver" Tuesday to ensure they would not be hit by a piece of debris, said US space agency NASA, urging better management of objects in Earth's orbit.

A warm Jupiter orbiting a cool star

A planet observed crossing in front of, or transiting, a low-mass star has been determined to be about the size of Jupiter. While hundreds of Jupiter-sized planets have been discovered orbiting larger sun-like stars, it is ...

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In physics, an orbit is the gravitationally curved path of one object around a point or another body, for example the gravitational orbit of a planet around a star.

Historically, the apparent motion of the planets were first understood in terms of epicycles, which are the sums of numerous circular motions. This predicted the path of the planets quite well, until Johannes Kepler was able to show that the motion of the planets were in fact elliptical motions.[citation needed] Isaac Newton was able to prove that this was equivalent to an inverse square, instantaneously propagating force he called gravitation.[citation needed] Albert Einstein later was able to show that gravity is due to curvature of space-time, and that orbits lie upon geodesics. This is the current understanding.

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