Shown here is an artist's impression of a star system where helium flows from one white dwarf onto another. The helium may end up exploding.
Click on image for full size
Credit: Tony Piro (2005)

Unusual Explosion Sparks New Insight Into the Life of Stars
News story originally written on November 5, 2009

An unusual explosion in a galaxy about 160 million light years away has helped scientists learn about another way that stars explode.

The more astronomers learn about how stars explode, the more we will understand how the Universe changes over time. These explosions influence the formation of stars and the growth of galaxies, and they produce nearly all of the metals that form the cores of planets like Earth.

The explosion made a flash of light that could be seen from Earth in 2002. Scientists thought it was an ordinary type of supernova, an explosion that destroys a massive star. But after re-examining data recorded by a telescope, they realized that this wasn’t just any ordinary exploding star.

The explosion's light didn't look like a typical supernova. It was much less bright and was three to four times faster.

This may not be a supernova at all, suggest scientists. Instead, two white dwarf stars orbiting around each other may have caused it.

White dwarfs are the ultimate end of stars like the Sun. They are very dense, with the mass of an entire star packed into a space roughly the size of Earth. When two white dwarfs orbit close together, matter flows from one to the other. This allows a thick layer of helium to build up. That helium can explode, which is what scientists suspect happened during this 202 event.

"We think this may well be a new physical explosion mechanism," said astronomer Alex Filippenko, one of the team’s scientists. "It whets my appetite for what else we might find."

Last modified February 5, 2010 by Lisa Gardiner.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Galaxies

During the early 1900's, which is not very long ago, astronomers were unaware that there were other galaxies outside our own Milky Way Galaxy. When they saw a small fuzzy patch in the sky through their...more

White Dwarfs

When stars like our own sun die they will become white dwarfs. As a star like our sun is running out of fuel in its core it begins to bloat into a red giant. This will happen to our sun in 5 Billion years....more

Density Definition Page

Density is a measure of how much mass is contained in a given unit volume (density = mass/volume). It is usually expressed in kg/m^3. Put simply, if mass is a measure of how much ‘stuff’ there is in an...more

What is mass?

Would it be more difficult to pull an elephant or a mouse? If you pulled each animal with the same amount of force, the elephant would respond less to pulling, even if he didn’t pull back at all. That’s...more

Triggers of Volcanic Eruptions in Oregon's Mount Hood Investigated

Scientists have learned that Mount Hood, Oregon's tallest mountain, has erupted in the past due to the mixing of two different types of magma. "The data will help give us a better road map to what a future...more

Oldest Earth Mantle Reservoir Discovered

The Earth's mantle is a rocky, solid shell that is between the Earth's crust and the outer core, and makes up about 84 percent of the Earth's volume. The mantle is made up of many distinct portions or...more

It’s Not Your Fault – A Typical Fault, Geologically Speaking, That Is

Some geologic faults that appear strong and stable, slip and slide like weak faults, causing earthquakes. Scientists have been looking at one of these faults in a new way to figure out why. In theory,...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA