Bert and Ernie have neutrino namesakes (Image: Moviestore/REX)

Welcome to Sesame Street, Antarctica, home of the astrophysical neutrino. It is now clear that a growing number of ghostly subatomic neutrinos – many affectionately nick-named after characters from the children’s TV programme – have been detected streaming in from outside the solar system and colliding with a detector at the South Pole.

Thought to come from exotic, distant objects such as supermassive black holes and exploding stars, these particles should open up a unique window on our cosmos.

Neutrinos are subatomic particles that have no electrical charge and only a very tiny mass, so they barely interact with the rest of the universe. Each second, billions of neutrinos pass through every spot on Earth’s surface, but the vast majority are from the sun. The IceCube neutrino observatory in Antarctica was set up in 2010 to search for neutrinos from much further afield and use them to probe the distant universe.


The first hints of astrophysical neutrinos came in April this year, when the IceCube collaboration reported detection of two very high-energy spikes in the data, which the group dubbed Bert and Ernie. Neutrinos are also thought to be produced when cosmic rays hit Earth’s atmosphere, so the team was initially cautious about assigning the pair an extraterrestrial origin.

Muppets from outer space

Next, in May, the team reported an additional 26 neutrino candidates. These neutrinos, along with the first two, have now all been confirmed in a paper published in the journal Science this week.

Some have even been given personable nicknames – the two most energetic of the 26 are called Miss Piggy and Mr Snuffleupagus, reports the New York Times. Another, from more recent data, is dubbed Big Bird.

Before IceCube started looking, the only detection of astrophysical neutrinos was in 1987, when a supernova in the Large Magellanic Cloud spat a few in our direction. Researchers are now looking forward to doing neutrino astronomy – using the particles to learn more about gamma-ray bursts and far-off black holes.

Since IceCube’s announcements earlier this year, one team of researchers has already suggested that these neutrinos could be the spawn of mysterious dark matter. Not bad for a bunch of Muppets.

Journal reference: Science, DOI: 10.1126/science.1242856