Changing Planet

Whirlpool Revisited

Who would have imagined that just a few weeks after I blogged about the 2005 supernova in the Whirlpool Galaxy, we’d be treated to a second supernova in the same galaxy.   It’s quite unusual to have two in the same nearby galaxy in such a short time.

The animation above was made from three images of the Whirlpool: (i) one taken just weeks before the 2005 event, (ii) one taken just a few weeks after the 2005 discovery of supernova SN 2005cs, and (iii) one taken a few nights ago showing SN 2011dh.  All three pictures were taken with the same equipment—a 10 inch reflector telescope and a cooled CCD camera.

Here’s the picture from a few nights ago showing SN 2011dh.  Note the interesting distant edge-on galaxy also appearing in the lower left corner of the image.

Whirlpool Galaxy showing SN 2011dh
And, here’s the picture from 2005 taken before the event of that year.

Whirlpool Galaxy in 2005

Kudos to discoverer, Amédée Riou, for noticing the subtle difference between his before and after images.   Such things are easy to miss.


More details on these images and the equipment used to acquire them can be found here:

Robert J. Vanderbei is chair of the Operations Research and Financial Engineering department at Princeton University and co-author of the National Geographic book Sizing Up the Universe. Vanderbei has been an astrophotographer since 1999, and he regularly posts new images on his astro gallery website.
  • Bobette Doerrie

    Thanks for the new information! I got to see the supernova with the 15″ refractor at the Three Rivers Foundation site near Crowell, TX, and I have been looking for more information on it. I will look for your blog.

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