Kepler remnant

Kepler remnant

Knots labeled on Kepler Supernova Remnant

Chandra X-ray image of the Kepler supernova remnant. Tracking these images over nearly a decade and a half shows that pieces of this debris field (knots) are still moving at about 23 million miles per hour over 400 years after the explosion was spotted by early astronomers.

IMAGE: NASA/CXC/Univ of Texas at Arlington/M. Millard et al.