NASA captures Kepler supernova remnant for more than 25 years

Madrid. A new video shows changes in Kepler’s supernova remnant using data from NASA’s Chandra X-ray Observatory captured over more than two and a half decades with observations taken in the years 2000, 2004, 2006, 2014 and 2025.

In this video, which is the longest ever released by Chandra, X-rays (blue) from the telescope have been combined with an optical image (red, green and blue) from Pan-STARRS.

The Kepler Supernova Remnant, named after the German astronomer Johannes Kepler, was first sighted in the night sky in 1604.

Today, astronomers know that a white dwarf star explodes when it exceeds a critical mass, after extracting material from a companion star or merging with another white dwarf. This type of supernova is known as Type Ia and scientists use it to measure the expansion of the universe.

Supernova remnants, the debris fields left behind after a stellar explosion, often glow brightly in X-rays because the material has been heated to millions of degrees by the explosion. The remnant is located in our galaxy, about 17 thousand light years from Earth, allowing Chandra to obtain detailed images of the debris and its evolution over time.

This latest video includes X-ray data from 2000, 2004, 2006, 2014 and 2025. This makes it the longest published by Chandra, thanks to its longevity.

“The plot of Kepler’s story is just beginning to unfold,” said Jessye Gassel, a graduate student at George Mason University in Virginia who led the work.

Gasel believes that it is “extraordinary” to be able to observe how the remains of this fragmented star collide with the material already ejected into space. The expert presented the new Chandra video and related research at the 247th meeting of the American Astronomical Society in Phoenix.

The researchers used the video to show that the fastest parts of the remnant are traveling at about 22.2 million kilometers per hour (2 percent of the speed of light), moving toward the bottom of the image. Meanwhile, the slower parts travel toward the top at about 6.4 million kilometers per hour (0.5 percent of the speed of light).

This large difference in speed is due to the gas that the remnant is penetrating towards the top of the image is denser than the gas towards the bottom. This provides scientists with information about the environments in which this star exploded.

“Supernova explosions and the elements they eject into space are the engine of new stars and planets,” said Brian Williams, of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and principal investigator of the new Kepler observations with Chandra. “Understanding exactly their behavior is crucial to understanding our cosmic history,” he adds.

The team also examined the width of the edges that form the blast wave from the explosion. This wave is the leading edge of the explosion and the first to encounter material outside the star. By measuring its width and propagation speed, astronomers learn more about the exploding star and its surroundings.