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Imagine that you're looking down the eyepiece of a telescope, staring at light from a distant galaxy that's been traveling for millions of years.  Now, imagine that you look at that galaxy again the next day, and you see something peculiar: a new speck of light shining brighter than all of the other stars in the galaxy put together.  That new speck of light is a supernova, the violent and explosive death of a star.  Finding one is pretty rare, but one person has not only discovered a supernova exploding, he's done it 42 times.  His name is Robert Evans, and he's a supernova superstar.

A supernova is tough to spot for a few reasons.  For one thing, in the average galaxy, a supernova only goes once every few decades, and even if you do see an extra speck of light, making sure it's a supernova is tricky.  You have to figure out if that point of light is new and whether it's changing over time.  That's why most supernovae are found by automated survey telescopes that look at huge chunks of the sky on a regular basis, comparing new images to older ones.  Then, a follow up investigation measures the supernova spectrum, the fingerprint of its light, to identify the elements in the explosion and figure out what type of supernova it is. 

But Evans, an Australian minister who spent decades exploring the night sky, found his supernovas manually, by carefully checking galaxies for changes.  When he first started observing back in the late 1950s, fewer than 60 supernovas had ever been discovered, and since Evans was observing in the Southern hemisphere, he had another problem: There weren't many images of the galaxies visible in the Southern sky because most early professional telescopes and the astronomers who ran them were North of the equator.  Evans needed to know what those galaxies usually looked like in order to figure out if a point of light was new and could be a supernova.  So he built his own database. 

By 1980, he had compiled hand-sketched observations and slides from photographic surveys for more than 1,000 galaxies.  That same year, he noticed a likely supernova candidate near the galaxy NGC 1316 and asked a professional astronomer to confirm his find.  But they were a little too slow, and credit for the discovery went to a team of Chilean astronomers instead.  Evans' first official supernova discovery came in February of 1981, when he found Supernova 1981A, the first supernova of the year.  Just a few weeks later, Evans found his second supernova in the same galaxy where the group of Chilean astronomers had beaten him to the previous year's discovery. 

Over the next few decades, Evans learned to identify more than 1,000 galaxies by sight, memorizing their star patterns so that he could tell when a point of light was out of place.  He earned a reputation as an efficient supernova hunter, and at top speed, he could check a galaxy a minute.  If the galaxies were close enough together in the sky, like in the Virgo cluster, he could do one in 30 seconds.  Between 1981 and 2008, Evans broke the world record for supernovas discovered by eye with 42 new supernovas, plus Evans also discovered a comet named 1996 J1 Evans-Drinkwater, after both him and the astronomer Michael Drinkwater who took the first photo of the comet.

These days, most supernovas are discovered using images taken by pre-programmed telescopes, which makes the process much faster.  In 2014, the Pan-Starrs consortium discovered 712 new supernovas, and the Catalina Real Time Transient Survey identified another 306.  These surveys end up generating thousands of images and sometimes they need help finding supernovas in them, which is where citizen science projects come in, like Snapshot Supernova, which you may remember us telling you about in SciShow Space News.

So even if you don't have a telescope good enough to find supernovas manually, Robert Evans style, you can still join the ranks of supernova superstars thanks to the wonders of the Internet.  Thanks for watching this episode of SciShow Space, and thanks especially to our Patrons on Patreon, who we couldn't do this without.  If you wanna help support this content, go to Patreon.com/SciShow and don't forget to go to YouTube.com/SciShowSpace and subscribe.

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