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One of a collection of stars that mark out Orion's upraised arm and weapon - either a club or a sword, depending on the particular depiction - that run northwards from the familiar group of bright stars representing the Hunter's body. f1 Orionis is one of a pair of blue dwarf stars designated 'f Orionis'. The other, f2 Orionis, lies somewhat to the east of f1. As well as falling close together in the sky, these two stars are also close together in space, each lying about 530 light years from the Solar System. On the other side of f1 Orionis from f2 in the sky, nearby to the west, is a patch of light known of Lower's Nebula, though in reality this emission nebula is more than two thousand light years beyond either of the two 'f' stars.

Though designated a 'dwarf' or main sequence star, f1 Orionis is rather larger and brighter than the Sun, which is also designated a dwarf star. It has more than four times the Sun's diameter, and emits more than 200 times as much light energy. The pattern of f1 Orionis' spectrum shows not only that it belongs to the B-type blue class of hot stars, but also that it is spinning on its axis at an unusually rapid rate.


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