New York (NY) – A 14-year-old student from New York State, Caroline Moore, has become the youngest ever person to discover a supernova.
The nova itself is on the titchy side: further observation has established that the object, called SN 2008ha, is a new type of stellar explosion, 1,000 times more powerful than a nova but 1,000 times less powerful than a normal supernova. Astronomers say that it may be the weakest supernova ever seen, and that it may have been a failed supernova where the explosion was unable to destroy the entire star.
“If a normal supernova is a nuclear bomb, then SN 2008ha is a bunker buster,” said team leader Ryan Foley, Clay fellow at the Harvard-Smithsonian Center for Astrophysics and first author on the paper reporting the findings. “From one perspective, this supernova was an underachiever, however you still wouldn’t want be anywhere near the star when it exploded.”
Caroline Moore was able to discover the object using a relatively small telescope, but some of the most advanced telescopes in the world were needed to determine the nature of the explosion. Data came from the Magellan telescopes in Chile, the MMT telescope in Arizona, the Gemini and Keck telescopes in Hawaii, and NASA’s Swift satellite.
In typical supernova explosions, light from different chemical elements (such as calcium or iron) is smeared out across the electromagnetic spectrum by the Doppler effect. Because the ejected bits of the star were moving at a quarter the usual speed, the light wasn’t as smeared out, allowing the team to analyze the composition of the explosion to a new precision.
“You can imagine many ways for a star to explode that might resemble SN 2008ha,” said Robert Kirshner, Clowes Professor of Science at the Harvard-Smithsonian Center for Astrophysics. “It could have been a massive star suddenly collapsing to form a black hole, with very little energy leaking out. But it looks a lot like its brighter cousins, which we think are nuclear explosion of white dwarfs. Maybe this one was an explosion of that general type, just much, much weaker.”
One reason astronomers haven’t seen this type of explosion before might be because they are so faint. “SN 2008ha was a really wimpy explosion,” said Alex Filippenko, leader of the University of California, Berkeley supernova group. “Coincidentally, the youngest person to ever discover a supernova found one of the most peculiar and interesting supernovae ever. This shows that no matter what your age, anyone can make a significant contribution to our understanding of the Universe.”
The paper has been accepted for publication in the Astronomical Journal and is available online here.