Peculiar, junior-sized supernova discovered by New York teen

June 11, 2009,

In November 2008, Caroline Moore, a 14-year-old student from upstate New York, discovered a supernova in a nearby galaxy, making her the youngest person ever to do so. Additional observations determined that the object, called SN 2008ha, is a new type of stellar explosion, 1000 times more powerful than a nova but 1000 times less powerful than a supernova. Astronomers say that it may be the weakest supernova ever seen.

Even though this was a weakling compared to most supernovae, for a short time SN 2008ha was 25 million times brighter than the sun. However, since it is 70 million light years away, it appeared very faint viewed from Earth.

The peculiar object effectively bridged the gap between a nova (a nuclear explosion on the surface of an old, compact star called a white dwarf) and a type Ia (the destructive death of a white dwarf caused by a runaway nuclear reaction starting deep in the star). SN 2008ha likely was 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 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 (the same principle that makes a police siren change pitch as it passes). Because the ejected bits of the star were "only" moving at 4.5 million miles per hour (compared to 22 million miles per hour for a typical supernova), 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 . 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, which monitors thousands of relatively nearby galaxies with a robotic telescope at Lick Observatory in California. But a new generation of telescopes and instruments is beginning to search greater distances than ever before, effectively monitoring millions of galaxies. Foley's team concludes that hundreds of this type of event may be spotted in the next few years.

"Coincidentally, the youngest person to ever discover a supernova found one of the most peculiar and interesting supernovae ever," remarked Filippenko. "This shows that no matter what your age, anyone can make a significant contribution to our understanding of the Universe."

Source: Harvard-Smithsonian Center for Astrophysics (news : web)

Explore further: Chandra sees brightest supernova ever

Related Stories

Chandra sees brightest supernova ever

May 7, 2007

The brightest stellar explosion ever recorded may be a long-sought new type of supernova, according to observations by NASA's Chandra X-ray Observatory and ground-based optical telescopes. This discovery indicates that violent ...

White Dwarf 'Sibling Rivalry' Explodes into Supernova

November 1, 2007

Astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) have found that a supernova discovered last year was caused by two colliding white dwarf stars. The white dwarfs were siblings orbiting each other. They ...

The wild, hidden cousin of SN 1987A supernova

September 25, 2008

The supernova, called SN 1996cr, was first singled out in 2001 by Franz Bauer. Bauer noticed a bright, variable source in the Circinus spiral galaxy, using NASA's Chandra X-ray Observatory. Although the source displayed some ...

Possible progenitor of special supernova type detected

February 13, 2008

Using data from NASA's Chandra X-ray Observatory, scientists have reported the possible detection of a binary star system that was later destroyed in a supernova explosion. The new method they used provides great future ...

The Gobbling Dwarf that Exploded

July 13, 2007

A unique set of observations, obtained with ESO's VLT, has allowed astronomers to find direct evidence for the material that surrounded a star before it exploded as a Type Ia supernova. This strongly supports the scenario ...

Swift sees double supernova in galaxy

June 26, 2007

In just the past six weeks, two supernovae have flared up in an obscure galaxy in the constellation Hercules. Never before have astronomers observed two of these powerful stellar explosions occurring in the same galaxy so ...

Recommended for you

HESS J1943+213 is an extreme blazar, study finds

June 21, 2018

An international group of astronomers have carried out multi-wavelength observations of HESS J1943+213 and found evidence supporting the hypothesis that this gamma-ray source is an extreme blazar. The finding is reported ...

'Red nuggets' are galactic gold for astronomers

June 21, 2018

About a decade ago, astronomers discovered a population of small, but massive galaxies called "red nuggets." A new study using NASA's Chandra X-ray Observatory indicates that black holes have squelched star formation in these ...

The Rosetta stone of active galactic nuclei deciphered

June 21, 2018

A galaxy with at least one active supermassive black hole – named OJ 287 – has caused many irritations and questions in the past. The emitted radiation of this object spans a wide range – from the radio up to the highest ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

omatumr
5 / 5 (2) Jun 14, 2009
CONGRATULATIONS, CAROLINE!

It is great that you could experience the joy of discovery.

I wonder if your discovery was helped by lower levels of interference from nearby lights in upstate New York.

Keep up the good work!
Oliver K. Manuel

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.