Chandra and LETG celebrate 15th anniversary

Fifteen years ago, NASA’s Chandra X-ray Observatory was launched into space aboard the Space Shuttle Columbia. Since its deployment on July 23, 1999, Chandra has helped revolutionize our understanding of the universe through its unrivalled X-ray vision. SRON provided the Low Energy Transmission Grating (LETG) for Chandra in collaboration with the Max Planck Institut für Extraterrestrische Physik (MPE) in Garching (near München). With this grating, astronomers were able to take a closer look at high energetic processes around astronomical objects, such as black holes, for the very first time.

The Crab Nebula, as captured by Chandra. Low, medium, and high-energy X-rays are shown as red, green, and blue respectively (NASA/CXC/SAO).

Chandra, one of NASA’s current “Great Observatories” along with the Hubble Space Telescope and Spitzer Space Telescope, is specially designed to detect X-ray emission from hot and energetic regions of the Universe.

With its superb sensitivity and resolution, Chandra has observed objects ranging from the closest planets and comets to the most distant known quasars. It has imaged the remains of exploded stars, or supernova remnants, observed the region around the supermassive black hole at the centre of the Milky Way, and discovered black holes across the Universe. Thanks to Chandra major advance have also been made in the study of dark matter and dark energy.

Many of Chandra’s extraordinary discoveries have been made possible using its Low Energy Transmission Grating (LETG). SRON was the principal investigator institution for LETG, and the only non-American institute to play a large role in the building of the observatory.

Collage of Four Supernova Remnants illustrate Chandra’s unique ability to explore high-energy processes in the cosmos: the Crab Nebula, Tycho, G292.0+1.8, and 3C58 (NASA/CXC/SAO).

“Even though LETG is not the most used instrument aboard Chandra, it did its job very well over the past 15 years,” says Jelle Kaastra, one of SRON’s scientists who has been involved in the project since the nineties. “With the use of LETG, we managed to observe the first ever spectra of gas flowing rapidly away from a giant black hole. But also in recent studies LETG has proven to be a very powerful instrument – even after fifteen years.”

To celebrate Chandra’s 15th anniversary, NASA released four new images of supernova remnants – the Crab Nebula, Tycho, G292.0+1.8, and 3C58. These supernova remnants are very hot and energetic and glow brightly in X-ray light, which allows Chandra to capture them in exquisite detail.

Click here to go to the NASA website containing the four new images.