For more than 40 years, astronomers have speculated the extra lithium found in young stars were the result of massive stellar explosions, or novae. But, studying several novae turned up nothing. Until now.
Using telescopes at ESO’s La Silla Observatory and the Observatory of Pontificia Universidad Catolica de Chile, a team of astronomers detected lithium. The team of astronomers, led by Luca Izzo, observed Nova Centauri 2013 (V1369 Centauri).
Nova Centauri 2013 exploded in December 2013 and could be seen with the naked eye.
What is lithium’s story?
Lithium is believed to have been created by the Big Bang. But, the amounts of lithium observed throughout the universe has puzzled astronomers. Older stars, or Population II stars, have less lithium than expected. While certain younger stars, or Population I, have ten times more.
Population II stars are classified as older stars with a low heavy-element content. Population I stars, including our sun, are much richer in heavier chemical elements. Age isn’t the most important factor in these classifications. Population I stars can be several billion years old. It’s all about their composition.
The team of astronomers detected a lithium signature expelled at two million kilometers per hour from Nova Centauri 2013.
Co-author Massimo Della Valle explains why the lithium finding is so important:
“It is a very important step forward. If we imagine the history of the chemical evolution of the Milky Way as a big jigsaw, then lithium from novae was one of the most important and puzzling missing pieces. In addition, any model of the Big Bang can be questioned until the lithium conundrum is understood.”
Astronomers believe the amount of lithium expelled from the nova is less than a billionth of the mass of the Sun. That doesn’t seem like much, but the Milky Way is a big place. Billions of stars have exploded in its history according to astronomers. The estimated amount is enough to explain the surprisingly large amount of lithium in our galaxy.
For Luca Izzo, this finding was a great birthday present. “It is very exciting,” said Izzo. “To find something that was predicted before I was born and then first observed on my birthday in 2013!”
For the older astronomers, it ends a decades-long search.
The telescope behind the discovery
The team of astronomers used the MPG/ESO 2.2 meter telescope at the La Silla Observatory along with the ESO 0.5 meter telescope at the Observatory of Pontificia Universidad Catolica de Chile.
Let’s take a closer look at the MPG/ESO 2.2 meter telescope.
You don’t need a fancy new telescope to make new discoveries. This telescope was first used on June 22, 1983.
Three instruments make up the telescope: a 67-million pixel Wide Field Imager, a Gamma-Ray Burst Optical/Near-Infrared Detector and a high-resolution spectrograph called FEROS.
FEROS was specifically used to observe Nova Centauri 2013.
The Wide Field Imager has snapped some fantastic images over the years.
Here’s the deepest wide-field color image in the southern sky.
And, the Helix Nebula.
Today, the ESO no longer uses the telescope, but the Max Planck Society and Chilean astronomers still do.
Image credits: ESO