astronomy@iowa

On April 13 a Type II supernova was discovered in the unusual galaxy NGC4088. This particular 90-second image was taken by Cedar Amateur Astronomers charter member Doug Slauson on April 21, using his 9.25-inch Celestron Schmidt-Cassegrain telescope with an attached SBIG STV at f/3.75.

At a distance of 55 million light-years, NGC4088 is a spiral galaxy in the Ursa Major cluster that has some properties of a barred spiral. Designated SN2009dd, the supernova is thought to be a type II supernova—the result of a cataclysmic explosion of a massive supergiant star at the end of its thermonuclear life. After fusing less massive nuclei into more and more massive nuclei, the supergiant star eventually ends up with iron in its core and a dead-end. Since iron has the greatest binding energy of all nuclei, all reactions involving iron are endothermic and rob the star’s core of energy resulting in an inability to support the star against the crush of gravity due to its extreme mass. In a fraction of a second, the massive star’s core implodes triggering a shock wave that eventually rips the star apart is a spectacular explosion.

The energy released in the supernova explosion is almost unimaginable—in a few seconds, the destroyed star gives off more energy than 10,000 sun-like stars will emit over their entire 10 billion year main sequence lifetimes!