[img_inline align=”right” src=”http://padnws01.mcmaster.ca/images/Welch_Doug.jpg” caption=”Astrophysicist Doug Welch will deliver the next Science in the City public lecture on Tuesday, May 8. File photo.”]Repeating history isn't always a good thing. But imagine having the opportunity to observe a rare celestial event as if we were there, standing shoulder to shoulder with our ancestors hundreds of years ago.

Now imagine having state-of-the-art equipment such as large telescopes and modern instrumentation on hand to observe this celestial event — a supernova — a stellar explosion that produced as much light as millions and millions of stars together.

Astrophysicist Doug Welch describes supernovae as “spectacular in their own right,” noting that the supernova of 1006 was visible to the naked eye for 3.5 years after the outburst. In 2005, Welch was part of a team that discovered the light echoes from centuries old supernovae in one of the companion galaxies to the Milky Way.

Welch, a professor in the department of physics and astronomy, will be sharing the story of this discovery, the results to date and the ongoing research that seeks to better understand how supernovae work at the next Science in the City public lecture, Deja Vu All Over Again: Seeing Supernova Again…for the First Time. The lecture takes place on Tuesday, May 8 at 7 p.m. in The Hamilton Spectator Auditorium.

“There have been six bright supernovae since 1000 A.D. that have been seen by people with the unaided eye,” explains Welch. “The last one was in 1604 — well before any scientific instruments were developed. We thought that that light would be forever unavailable since it has 'passed us by.' But the light from the echoes is the light from the outburst that just took a longer path and so is arriving now.”

This is a free public lecture and all are welcome. To reserve your seat(s), please call 905-525-9140, ext. 24934 or e-mail sciencecity@mcmaster.ca.