A. Read (University of Leicester)/ESA
The European Space Agency's XMM-Newton space telescope has been in orbit since 1999, and it's constantly collecting information, even when it's just adjusting its position. This picture, a composite of more than 73,000 images, shows what happens when the telescope moves across the sky as it focuses its attentions from one object to another, leaving a slew of x-ray data in its path.
The telescope looks at x-ray data from high-energy objects like black holes, stellar wind and pulsars. Here you can see 1,200 slews from between 2001 and 2012.
It kind of looks like a giant orange broom, but that big, bright dot on the right is the Vela supernova remnant, one of the largest features in the sky visible by x-ray. In the center, you can see Scorpius X-1, the strongest source of x-ray emissions in the sky apart from the Sun.
A full catalog of XMM-Newton's slews can be accessed here.
[ESA]
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