- GPS satellites suggest a halo of dark matter is surrounding our planet
Ever since scientists have theorised that dark matter exists, concrete evidence of the elusive substance has continued to confound them.
Now, data from a number of GPS satellites suggest that a halo of the strange matter may be surrounding Earth, causing our planet to be heavier than first believed.
From his calculations, Professor Ben Harris from Texas University claims this halo could affect the Earth’s gravity and that the planet could be 0.005 and 0.008 per cent heavier than the mass established by the International Astronomical Union.
This would be the equivalent of a disc of dark matter around the equator which is 191km (120 miles) thick and 70,000 km (43,000 miles) across.
According to International Astronomical Union, the current Earth mass is quoted as 5,972,000, 000,000,000,000,000,000kg, or 5.972E24 kg.
Dark matter is considered crucial to theories explaining how the universe is expanding and how galaxies interact.
It is thought to make up 27 per cent of the universe, but despite huge amounts of funding and research effort, experiments have so far failed to confirm its presence.
In 2009, researchers at the Institute of Advanced Studies in Princeton, argued that changes in the speeds of space probes as they flew past the Earth could be explained by dark matter bound by Earth’s gravity.
The theory has now been put to the test by Professor Ben Harris at the University of Texas, according to a report by Anil Ananthaswamy in New Scientist.
Using data on the satellites in the U.S. GPS, Russian GLONASS and European Galileo groups, Professor Harris measured Earth’s mass as ‘felt’ by each satellite.
As satellites orbit the Earth, their location in space is determined by the Earth’s gravitational pull.
By using the data and location of these satellites, Professor Harris was able to estimate how strong this pull was, which in turn gave an indication to how heavy the Earth is.
‘The nice thing about GPS satellites is that we know their orbits really, really well,’ he told New Scientist.
Professor Harris is now planning to factor in changes to the satellites’ orbits due to the gravitational pull of the sun and moon.
If his calculations prove to be correct, satellites could help unlock some longstanding mysterious surrounding dark matter.
Scientists still have no concrete proof that dark matter exists, but the evidence for it is significant.
Galaxies, for example, could not rotate the way they do and hold their shape without the presence of dark matter, researchers say.
The quest to find it is now gaining pace. Last year one of the biggest quests in physics, the search for the enigmatic substance known as dark matter, failed to provide answers.
The Large Underground Xenon (LUX) experiment, the world’s most advanced test to find this elusive material, was unable to detect its presence after its first 90-day run.
A number of researchers are currently re-examining dark matter candidates once written off as unlikely, and considering unpopular ideas such as dark matter could be made out of something undetectable.
