It is rare and exciting to see any changes, even tiny movements in astronomical objects outside of our solar system. Most objects, even in our own galaxy, are so far away, they move or change too slowly to see any difference during our entire lives. However, incredibly, the above time lapse video is two images taken exactly 13 years apart - the first in October 2008 and the second in October 2021, a long time lapse indeed! Several things are noteworthy in the video. First, note the gas and dust, especially the red glowing filaments of hydrogen and helium seen to expand considerably*, in fact, the shell is moving outwards at nearly 1000 miles per second or 0.5 percent the speed of light. The nebula has, therefore, expanded nearly 1 trillion miles in the 13 years between images. Reversing this rate gives a nice calculation of the explosion origin at about 1000 years ago as seen by the ancient Chinese. Second, note the blue-white cloudy material illuminated by synchrotron radiation inside and throughout the nebula moving during its expansion. Third, note the movement of the yellow-orange star in the lower left corner of the image. The star is Tycho 1309-1640-1 and exhibits what is called proper motion since it is relatively nearby to us compared to all the other stars in this image. Proper motion is the movement of stars, each in their own path around our galaxy. Every star has its own proper motion; we can see this ones clearly over 13 years due to both its and our sun’s movement. Looking forward to the next timelapse image in a decade or so!

Click on video above to see full size video zoomed out!

Visit the main page for the Crab Nebula for more information on this supernova by clicking here.