Scientists at the European Organization for Nuclear Research (CERN) near Geneva have found a new subatomic particle that could be the Higgs boson, the basic building block of the universe.
A spokesman for one of the two teams hunting for the Higgs particle has said that while it is a preliminary result, they think it's very strong and very solid.
The Higgs boson, otherwise known as the God particle, is thought to give all other particles in the universe their mass.
Because the Higgs boson cannot be seen, scientists had to infer its existence. The process has been likened to proving the existence of wind; it cannot be seen, but it's known to exist from the effect it has on other things.
This inference is tested by smashing protons together in the Large Hadron Collider, a massive 27 kilometre-long particle accelerator that lies beneath the Franco-Swiss border near Geneva.
The British scientist after whom the subatomic particle is named, Professor Peter Higgs, first mooted its existence back in 1964.
Professor Higgs was present at the announcement of the results in Geneva on Wednesday and said later that the finding is an incredible thing to have happened in his lifetime.
"I certainly had no idea at the beginning, more than 40 years ago, because at the beginning people had no idea about where to look for it.
"It's really amazing for me to find out that it's really enough, shall we say, enough for a discovery claim."
The Higgs particle, although crucial for understanding how the universe was formed, remains theoretical.
It explains how particles clumped together to form stars, planets and even life.
It is the last undiscovered piece of the Standard Model that describes the fundamental make-up of the universe.
What scientists don't yet know from the latest findings is whether the particle they have discovered is the Higgs boson as described by the Standard Model, a variant of the Higgs or an entirely new subatomic particle that could force a rethink on the fundamental structure of matter.
The last two possibilities are, in scientific terms, the most exciting.
Dr David Krofcheck from Auckland University is a member of one of the teams responsible for the discovery.
He told Morning Report the research team has done a wonderful job. The discovery completes the Standard Model of particle physics, he said, though that model only accounts for 4% percent of matter in the universe.
Renowned physicist Stephen Hawking said it is an important result and should earn Peter Higgs the Nobel Prize.
A lesser-known contribution has come from the pioneering work of late Indian physicist Satyendra Nath Bose, after whom the term boson is named. In 1924, Professor Bose sent a paper to Albert Einstein that laid the basis for describing a fundamental class of sub-atomic particles.
Listen to Dr Krofcheck