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Music of the Spheres: 'Supernovae: Past, Present, and Future' - Sold Out

Virginia Trimble

Astronomers use the phrase "historical supernovae" to mean stellar explosions that were seen and recorded by someone before the invention of the telescope. All were, therefore, necessarily within our own Milky Way Galaxy. There are six or eight of them, most seen first by Chinese astronomers, though there are also records from Japan, Korea, Europe and an Arab site. The last two historical supernovae were caught in Asia, but have attached to them the names of Tycho Brahe (1572) and Johannes Kepler (1604). Curiously, there have been no supernovae found within our Galaxy since the 1608 invention of telescopes, and we are definitely overdue for one! In the interim however, many hundreds of events have been discovered and studied in other galaxies, assigned types and ranges of properties, and attributed to different causes of the explosions, some nuclear and some gravitational. The supernovae 1987A (the first one seen that year) was, just barely, a naked eye event, blowing up in a nearby small galaxy, called the Large Magellanic Cloud, because Magellan was the first European to see it. Like Tycho's and Kepler's supernovae, this is an example of European dominance of astronomy from 1400 to 1850 or so.  He also saw the Small Magellanic Cloud, which obviously had also been known to millions of residents of Africa, Australia, and South America for thousands of years. Whether 1987 counts as "historical" depends on how old you are. Because they are close to us, the remnants of the historical SNe yield some very impressive images, in visible light, but also in radio and X-ray wavelengths. They are obviously also  trying to tell us more about supernovae in general, because, long after the explosions, we have a chance to see how much energy, rotation, and magnetic field had to be involved, whether any of the star's core is left behind, how much stuff was blown out, and what it is made of. Most stars and galaxies in the universe are made mostly of hydrogen. This is definitely not true of supernova progenitors.  Indeed some contain no hydrogen at all, but only the products of a long series of nuclear reactions in their parent stars.

Speaker: Virginia Trimble, UC Irvine

Musical Performer: Melody of China

General tickets on sale at 12:00 noon, April 18th

Saturday, 07/07/18

Contact:

Website: Click to Visit

Cost:

$45 - $199

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Lick Observatory

7299 Mt. Hamilton Rd
Mt. Hamilton, CA 95140


Phone: 408-274-5061
Website: Click to Visit