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In this month: January

7 January 1610 Galileo discovers four moons orbiting the planet Jupiter. Looking at what he thought were a group of stars, he noted the objects appeared to move in a regular pattern and realised they were in orbit around Jupiter. Today, Jupiter’s four largest satellites—Io, Europa, Ganymede, and Callisto—are named the Galilean Moons in honour of their discoverer. They were the first objects found to orbit another planet. His discoveries would lead to the development of modern astronomy and provided evidence for the Copernican understanding of the universe, the idea that everything in existence did not move around the Earth. 26 January 1946 Ruby Payne-Scott carries out the first use of a radi

Did You know? the North Star

DID YOU KNOW This month . . . The North Star The North Star or Pole Star is located close to the north celestial pole, the point around which the entire northern sky revolves. It is almost straight above Earth's north pole and when seen from Earth it appears to always stay in the same place in the sky. The image below was constructed by Jim Thomas (wiki commons). The North Star changes due to the slow wobble of the Earth known as Precession. Currently the North Star is Polaris. It became the North Star around AD 500 and will move closer to straight above the Earth's north pole until sometime in AD 2102, then it will move away again. It will be the closest star to the North Pole until about A

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