Astronomy Picture of the Day (APOD) is a website provided by NASA and Michigan Technological University (MTU).

It reads: "Each day a different image or photograph of our universe is featured, along with a brief explanation written by a professional astronomer.

"[1] The photograph does not necessarily correspond to a celestial event on the exact day that it is displayed, and images are sometimes repeated.

[4] When the APOD website was created, it received a total of 14 page views on its first day.

[12] During the United States federal government shutdown of 2013, APOD continued its service on mirror sites.