About 11,000 years ago a star in the constellation of Vela exploded. This bright supernova may have been visible to the first human farmers. Today the Vela supernova remnant marks the position of a relatively close and recent explosion in our Milky Way Galaxy. A roughly spherical, expanding shock wave is visible in X-rays. In the optical photograph shown here, the 100+ light-years span spherical blast wave is shown in detail. As gas flies away from the detonated star, it reacts with the interstellar medium, knocking away closely held electrons from even heavy elements. When the electrons recombine with these atoms, light in many different colors and energy bands is produced.
(Text adapted from the Astronomy Picture of the Day website)

This image has been chosen as NASA Astronomy Picture of the Day for February 13, 2007.

The Vela SNR image presented here is one of the largest deep-sky image ever released; the full-resolution version is a whopping 1.018 gigapixel, or 1,018 megapixel. For comparison, a modern digital camera produces images of just 8-10 megapixel and a good modern LCD screen is able to show just 1/1000^th of the full-res in a time. The uncompressed version of the file is nearly 3 Gigabytes.

The image's field of view is about 9.3 × 8.5 arc degrees, so it shows a plague of sky nearly wide as 19 times the apparent diameter of the full Moon.

Remarkable features Moving the cursor over the image will bring up an annotated version. Clicking on the image will bring up the zoomable high resolution version (half-res). NGC 2736 is the Pencil Nebula, a shockwave expanding through interstellar space at 500,000 kilometers per hour. The Pencil Nebula is part of the Vela Supernova Remnant. Initially the shockwave was moving at millions of kilometers per hour, but the weight of all the gas it has swept up has slowed it considerably.     Vela SNR Video Why don't you take three minutes of additional relax? Click the "play" button, adjust the volume and start a brief voyage throughout the delicate filaments of the Vela Supernova Remnant, the nice Gum nebulas and the many clusters rich of stars that populate this plague of sky. Enjoy! Do you want a better quality? To download the video in nearly DVD-quality right click here, then click "Save target as..." on the menu (format WMV- about 32 Megabyte).   Find Chart The position of the Vela Supernova Remnant (in the red circle) in Vela. Image from Cartes du Ciel.

In order to produce the color image seen here, I worked with data coming from 19 different photographic plates taken at the UK Schmidt Observatory starting from 1975.  The original file is 33,421 × 30,477 pixels with a resolution of about one arc second per pixel. The image show an area of sky large 9.3° × 8.5° (for comparison, the full-Moon is about 0.5° in diameter).
Copyright: Davide De Martin (http://www.skyfactory.org).

Links

• http://fuse.pha.jhu.edu/~wpb/hstvela/hstvela.html - Bill Blair's Vela Supernova Remnant File;
• http://wave.xray.mpe.mpg.de/rosat/publications/highlights/vela_snr - Discovery of explosion fragments outside of the Vela supernova remnant shock-wave boundary (ROSAT All-Sky Survey);
• More links by Google.

This image is a composite from black and white images taken with the Anglo Australian Observatory's 48-inch (1.2-meter) UK Schmidt Telescope. Credit: Anglo-Australian Observatory, UK Schmidt Telescope, Digitized Sky Survey.