An end to our darkest secret? Scientists close to explaining dark matter

A £1.3bn experiment could soon reveal the true nature of the mysterious dark matter

Science Editor

Scientists are close to solving one of the biggest mysteries of the universe. They have found tantalising evidence that might soon explain dark matter – the 95 per cent of cosmic “stuff” that we know exists, yet cannot see or detect with conventional scientific instruments.

The first results of a £1.3bn experiment on the International Space Station suggest that dark matter is composed of sub-atomic particles that permeate all regions of space, with a combined gravitational force that influences the movements of the biggest objects, from planets and solar systems to stars and galaxies.

For decades, cosmologists have argued over the nature of dark matter. Estimates show that we can see only about 5 per cent of the matter in the universe – composed of visible objects such as stars and galaxies – and that a further 24 per cent of mass is in the form of invisible dark matter, with the rest of the Universe composed of something even more mysterious called dark energy.

Some cosmologists have suggested that the “missing mass” of the universe is made of massive objects such as brown dwarf stars that do not emit light, whilst other experts have pointed to the possibility of a cosmic-wide ocean of sub-atomic particles that permeate everywhere, yet do not interact with ordinary matter.

Now the alpha magnetic spectrometer (AMS) instrument on the space station has detected the strongest signs yet that dark matter may indeed be composed of sub-atomic particles known as neutralinos, which are so weakly-interacting that they pass straight through the Earth without stopping.

Professor Sam Ting, the head of the AMS experiment, released the first 18 months of data from the AMS experiment yesterday at a scientific seminar at the European Organisation for Nuclear Research (Cern) in Geneva – but disappointed many by declining to confirm that dark matter had actually been found.

“These observations show the existence of a new physical phenomena, whether from a particle physics or an astrophysical origin,” Professor Ting said. Essentially, the results support the existence of dark matter in the form of sub-atomic particles, but other explanations for the results are still possible, he said.

“I’ve never made a mistake and this is a very difficult experiment,” Professor Ting said in reply to questions about whether he had further preliminary results to support the neutralino theory.

“It took us 18 years to build this detector. Nobody will be foolish enough to repeat this so we want to do it correctly,” he said.

The AMS experiment does not detect neutralinos directly. Instead, it is designed to detect the electrons and positively charge particles called positrons that are, in theory, given off when neutralinos collide in a process known as annihilation.

The AMS has indeed detected an excess of positrons that supports the sub-atomic particle model of dark matter, but these positively-charged particles could also be the result of nuclear interactions going on in distant pulsars – rotating neutron stars in space.

“AMS is the first experiment to measure to 1 per cent accuracy in space. It is this level of precision that will allow us to tell whether our current positron observation has a dark matter or pulsar origin,” Professor Ting said.

“Over the coming months, AMS will be able to tell us conclusively whether these positrons are a signal of dark matter, or whether they have some other origin,” he said.

Start your day with The Independent, sign up for daily news emails
ebooks
ebooksA special investigation by Andy McSmith
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Online Sales and Customer Services Associate

£14000 - £16000 per annum: Recruitment Genius: Full time and Part time positio...

Ashdown Group: IT Manager - Salesforce / Reports / CRM - North London - NfP

£45000 per annum: Ashdown Group: An established and reputable Not for Profit o...

Recruitment Genius: Sales Ledger & Credit Control Assistant

£14000 - £17000 per annum: Recruitment Genius: A Sales Ledger & Credit Control...

Recruitment Genius: Project Administrator

£16000 - £19000 per annum: Recruitment Genius: A Project Administrator is requ...

Day In a Page

Syrian conflict is the world's first 'climate change war', say scientists, but it won't be the last one

Climate change key in Syrian conflict

And it will trigger more war in future
How I outwitted the Gestapo

How I outwitted the Gestapo

My life as a Jew in wartime Berlin
The nation's favourite animal revealed

The nation's favourite animal revealed

Women like cuddly creatures whilst men like creepy-crawlies
Is this the way to get young people to vote?

Getting young people to vote

From #VOTESELFISH to Bite the Ballot
Poldark star Heida Reed: 'I don't think a single bodice gets ripped'

Poldark star Heida Reed

'I don't think a single bodice gets ripped'
The difference between America and Israel? There isn’t one

The difference between America and Israel? There isn’t one

Netanyahu knows he can get away with anything in America, says Robert Fisk
Families clubbing together to build their own affordable accommodation

Do It Yourself approach to securing a new house

Community land trusts marking a new trend for taking the initiative away from developers
Head of WWF UK: We didn’t send Cameron to the Arctic to see green ideas freeze

David Nussbaum: We didn’t send Cameron to the Arctic to see green ideas freeze

The head of WWF UK remains sanguine despite the Government’s failure to live up to its pledges on the environment
Author Kazuo Ishiguro on being inspired by shoot-outs and samurai

Author Kazuo Ishiguro on being inspired by shoot-outs and samurai

Set in a mythologised 5th-century Britain, ‘The Buried Giant’ is a strange beast
With money, corruption and drugs, this monk fears Buddhism in Thailand is a ‘poisoned fruit’

Money, corruption and drugs

The monk who fears Buddhism in Thailand is a ‘poisoned fruit’
America's first slavery museum established at Django Unchained plantation - 150 years after slavery outlawed

150 years after it was outlawed...

... America's first slavery museum is established in Louisiana
Kelly Clarkson: How I snubbed Simon Cowell and become a Grammy-winning superstar

Kelly Clarkson: How I snubbed Simon Cowell and become a Grammy-winning superstar

The first 'American Idol' winner on how she manages to remain her own woman – Jane Austen fascination and all
Tony Oursler on exploring our uneasy relationship with technology with his new show

You won't believe your eyes

Tony Oursler's new show explores our uneasy relationship with technology. He's one of a growing number of artists with that preoccupation
Ian Herbert: Peter Moores must go. He should never have been brought back to fail again

Moores must go. He should never have been brought back to fail again

The England coach leaves players to find solutions - which makes you wonder where he adds value, says Ian Herbert
War with Isis: Fears that the looming battle for Mosul will unleash 'a million refugees'

The battle for Mosul will unleash 'a million refugees'

Aid agencies prepare for vast exodus following planned Iraqi offensive against the Isis-held city, reports Patrick Cockburn