Chilean researchers add new layer of mystery to dark matter
A recent study from two Chile-based observatories contradicts leading theories to explain the intangible substance thought to comprise 80 percent of the universe.
Monday, April 30, 2012
Category: Education - Technology
Artist’s impression of the expected dark matter distribution around the Milky Way. (Photo courtesy of European Southern Observatory)
It’s one of the most enigmatic mysteries of our age - an invisible substance that is believed to make up more than 80 percent of all matter in the universe.
Now a study by Chilean researchers at two of the country’s world leading astronomical facilities has shaken up a few theories that explain just how dark matter actually functions.
"Our results contradict the currently accepted models,” said study lead author Christian Moni-Bidin, an astronomer at the Universidad de Concepción in Chile.
It was previously thought that dark matter is comprised of an unknown particle that interacts normally with gravity but which has a tenuous relationship with all other known cosmic forces.
The idea of a substance that was only detectable by its gravitational pull conveniently explained the anomalies in star movements in the Milky Way - which seem to operate as if something else is exerting a gravitational pull.
According to these theories - widely accepted in the astronomical community - the space surrounding the sun should be heavy in dark matter.
However, the recent Chilean study found no trace of the substance.
Using telescopes at the La Silla Observatory and the Las Campanas Observatory, the team mapped the motions of more than 400 red giant stars up to 13,000 light-years from the sun.
"The amount of mass that we derive matches very well with what we see - stars, dust and gas - in the region around the sun," Moni-Bidin said. "But this leaves no room for the extra material, dark matter, that we were expecting. Our calculations show that it should have shown up very clearly in our measurements. But it was just not there!"
“The mystery of dark matter has just become even more mysterious,” said Moni-Bidin.
The scientists will detail their findings in a future issue of the Astrophysical Journal.
For more information see the European Southern Observatory’s official website.