By: Yimo Liu
Have you ever wondered about the Milky Way galaxy when you were bored? Well, the galaxy has many secrets to tell us.
There’s a kind of space particle called a neutrino. It doesn’t have much mass or an electrical charge and neutrinos are also sometimes known as ‘ghost particles’. They got their name because they pass through things without leaving a trace of themselves, just like ghosts. Scientists know where all the other space objects come from, but they don’t know anything about neutrinos. So now it’s officially time to study neutrinos.
The first signs of neutrinos that scientists have found were in the Milky Way galaxy. The scientists mapped out the neutrinos and created a new version of our galaxy.
The map hinted at possible sources of neutrinos with high energy. They could probably be the left-overs of old supernovas. Or, the neutrinos could be from explosive stars. People say that scientists need to conduct more research about neutrinos.
The new map of the Milky Way galaxy was revealed on June 30th in Science. During the scientists’ research, they only found neutrinos with high energy outside of the Milky Way galaxy. Two were created from black holes that were shredding out stars. The others were from a type of galaxy called a blazar. A blazar is an active galactic nucleus with a relativistic jet directed very nearly towards an observer. Relativistic beaming of electromagnetic radiation from the jet makes blazars appear much brighter than they would be if the jet were pointed in a direction away from Earth.
“It’s clear now that researchers are spotting neutrinos from both inside and outside our galaxy,” says Kate Scholberg, a physicist at Duke University in Durham, N.C., who did not take part in the new mapping project. “There’s so much more to learn,” she says. “It can be tremendous fun to figure out how to see the universe with neutrino eyes.”
In Antartica, scientists have an outdoor lab with a neutrino detector called IceCube. The detector can live with subzero temperatures. It can be stuck in thick, cold ice and not freeze. To be able to detect ghost particles, the detector is very long; about 1 kilometer long. Kurahashi Neilson and her team decided to help. They used the IceCube to find ghost particles. “You can train the neural nets to identify which events are worth keeping,” Kurahashi Neilson explains.
Neilson has volunteered since 2017. She also needed to make a new map for the neutrinos.