[petuniasevan]

Astronomy Fun Fact:

XTE J1118+480 is known as an "X-ray nova" because it undergoes occasional eruptions followed by long periods of dormancy. The above image was obtained in an exposure of 7 1/2 hours.

[petuniasevan]

[BossyRoofer]

WOW! X-ray rainbows. Good job APOD!

[RightWhale]

The grating of the spectrometer is round rather than a series of parallel straight lines. It's a mechanical device of metal rather than glass and the framework is aluminum and the optical parts are gold.

[firewalk]

Thanks!

[aomagrat]

That looks like one of those velvet black light posters I had on my wall back in the early '70's.