The first congressional authorization for the X-ray telescope came in 1987.

CNN: Collins

"It's correlating the increasing intensity in different bands that provides really important clues about the structure of the source, " Prof Madejski - a co-investigator on the NuStar X-ray telescope, told BBC News.

BBC: Blazar Markarian 421's flare-up is cosmic coincidence

In 1999, it deployed the powerful Chandra X-ray space telescope, with the first female commander at the helm, Eileen Collins.

CNN: NASA weighed retiring Columbia in 2001

Many Americans recognize the unsurpassed science and inspiration that have come from the Hubble Space Telescope over the past two decades, as well as from its less famous sister satellites like the Chandra X-ray Observatory, the Spitzer Space (Infrared) Telescope and the Fermi gamma-ray observatory.

CNN: Space is still the new frontier

The observations from the Chandra space telescope are the deepest X-ray images ever obtained, viewing events that are 10 billion light-years away.

BBC: NEWS | Science/Nature | Deepest X-rays tell merger story

The loop was seen using the European space telescope XMM-Newton to study it in X-ray wavelengths.

BBC: Arches Cluster, Leicester