Credit: X-ray: NASA/CXC/Univ. of Wisconsin-Madison/S.Heinz et al; Optical: DSS

Chandra data of Circinus X-1 reveal a set of four rings that appear as circles around the neutron star, providing a rare opportunity to determine the distance to an object on the other side of the Milky Way galaxy. These rings can be seen in the composite image of X-rays from Chandra (red, green, and blue) with a visible light image from the Digitized Sky Survey. These rings are light echoes, which are produced when a burst of X-rays from the star system ricochets off of clouds of dust between Circinus X-1 and Earth. By combining the X-rays with radio data, astronomers can use relatively simple geometry to pinpoint the location of the intervening clouds and then Circinus X-1.

Provider: Chandra X-ray Observatory

Image Source: http://chandra.harvard.edu/photo/2015/cirx1/

Curator: Chandra X-ray Observatory, Cambridge, MA, USA

Image Use Policy: http://chandra.harvard.edu/photo/image_use.html