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A red-orange star lying towards the southern end of the arc of stars known as Orion's Shield. 5 Orionis appears to fall very close in the sky to Pi5 Orionis, a blue star that outshines it significantly, appearing more than four times brighter as seen from Earth. Despite being by far the fainter of the two stars, 5 Orionis is actually the nearer of the two to the Solar System at a distance of some 485 light years (Pi5 Orionis is more than twice as far away, but much more luminous).

5 Orionis is the red-orange star marked by the reticle in the centre of this image, while the brighter blue star to the east and south is Pi5 Orionis, a close neighbour of 5 Orionis as seen from Earth, but actually a great deal farther away. Imagery provided by Aladin sky atlas

Though outshone by Pi5 Orionis, 5 Orionis is a massive and luminous red giant star in its own right. It has a diameter nearly seventy times greater than the Sun, and emits more than two hundred times as much visible light. 5 Orionis is an eruptive variable, whose brightness shows slight shifts over time as bursts of material are thrown out by the star.


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