NASA's Wide Field Infrared Survey Explorer satellite has captured an image of a star that is flying through space faster than a rocket launches from the pad.
The star is Zeta Ophiuchi, in the constellation Ophiuchus. It is 20 times as massive as the sun and appears as a reddish, middling star in the summer sky. The star was caught plowing through lanes of dust in space.
As the star travels, its powerful winds push gas and dust out of its way and into what is called a bow shock. The material in the bow shock is so compressed that it glows with infrared light that WISE can see. The effect is similar to the wake created when a boat moves through the water, pushing a wave in front of it.
As WISE is designed to take pictures in the infrared, the images the probe caught have been recalibrated so human beings can see them. The star itself looks blue as a result, showing that it is very hot relative to the background.
Ordinarily, the bow shock in front of the star would be invisible and the dust would obscure the star, which is why it appears reddish to the naked eye. But the infrared images allow scientists to see through the dust, and observe the star itself more easily. If it were not for the dust clouds surrounding the star, it would be one of the brightest in the sky and look bluish. Zeta Ophiuchi is relatively far away at 458 light years, but it is 68,000 times more luminous than the sun and eight times as large.
Zeta Ophiuchi once orbited around an even heavier star. But that star exploded in a supernova, shooting Zeta Ophiuchi away like a bullet. A supernova is an explosion created when a massive star runs out of nuclear fuel. Zeta Ophiuchi itself is due to become a supernova, though that won't happen for another few million years.