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I'm a SINner!

HST images of SN1987A

As part of the SINS project, many images of supernova 1987A have been made with the Hubble Space Telescope.

  • a picture This is an image of the supernova and surrounding nebulosity. It was made by first adding together many images taken over a period of three years, subtracting off two nearby stars (which can be seen in the newer, "fixed" HST image), and then cleaning the image up using a process called deconvolution. This image appears in a paper submitted to The Astrophysical Journal, which came out February 1st, 1995.

  • a picture This image was taken after HST had been `fixed', correcting the flaw in the optics. It was taken as part of the Wide Field/Planetary Camera assessment just after the fix. Note that the loops seen here are also visible in our earlier image (I sometimes need to pat myself on the back). Note also that this image is rotated a bit compared to mine, above.

  • a picture This image shows the ring in [OIII] fading over a three year period. Each image is to the same brightness scale, except the first one which is so bright it is further scaled down by a factor of two. The neat thing here is that the ring faded fairly evenly all the way around; the bright region to the upper right faded about as fast as the dimmest region to the lower left. The oddly shaped spot to the lower left of the ring in each image is the residual from subtracting a bright nearby star. In order, the images are from a) August 24, 1990; b) December 13, 1991; c) April 13, 1992; d) September 15, 1992, e) May 1, 1993, and e) October 20, 1993.

  • a picture This shows the ring in three different types of light: The first is in the light of doubly ionized oxygen ([OIII] at 5007 Angstroms); the second is a sharpened version of the same image (note how the supernova debris in the center of the ring got noticeably smaller after sharpening); the third shows hydrogen (H beta at about 4860 Angstroms) and the fourth in nitrogen ([NII] at about 6580 Angstroms). Note that the structure is very similar in all three filters.

  • a picture This was an odd idea: what if I took the images of the ring and resampled them in elliptical coordinates? If done correctly, the ring would be "straightened out" into a line. I did it, and here are the results. Besides being a curiosity, it also helps in finding some of the properties of the ring (such as thickness, axes lengths, etc.). The six images going from top to bottom are the same as the six ring images above, except the that the images are negative; that is, black is where the image is bright, and white is where it is dim.

  • Smile! This is an actual image of the supernova SN1987A itself taken with the Hubble Space Telescope. I was trying to bring out middle range brightness details in the ring around the supernova, and scaled the images so that bright and dark values both came out as black (technically, I used a sin2 color lookup table). To my amazement, this popped up. Maybe someday I'll send it in to the National Enquirer. Each pixel is about 1/45th of an arcsecond across, which, at the distance of the ring (50 kiloparsecs) turns out to be about 160 billion kilometers each. The whole ring is about 13 trillion kilometers across, or just a bit over a light year. And oh-- have a nice day! ;-)
  • More images have been taken, and maybe someday I will install them here. In the meantime, check out Bill Arnett's SN87A page .

    ©2008 Phil Plait. All Rights Reserved.

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