The mystery of dark matter may have had some more light shed upon it today after an announcement from NASA. Scientists from NASA have announced that they may have found hints of the mysterious substance after reviewing data from an experiment on the International Space Station.
The new data comes from the newest addition to the ISS, the Alpha Mass Spectrometer. The Alpha Mass Spectrometer is a particle physics experiment module that took 16 years to develop, construct, launch into space, and begin running its experiments at a cost of $1.6 billion. The device measures cosmic rays and sends the results to scientists back on Earth. This latest patch of results could provide us with new insights into the fundamental nature of the universe.
Dark matter is a building block of the universe that scientists know extremely little about. It makes up 26% of the known universe, according to scientists. It does not absorb, reflect, or emit light, the "dark" part of its name. Up to now the only effect that have suggested its existence has been the gravitational effect it has on regular matter.
The AMS has confirmed theories that space is filled with a wealth of high-energy particles, much more than should exist. Such an amount of high-energy particles could be seen as evidence for dark matter. Scientists have long theorized that high-energy collisions of dark matter would produce high-energy particles and any excess that could not be explained by normal non-dark matter cosmic phenomena would be more evidence for the mysterious substance. The two areas in which scientists theorized that this would be most easily observed was in a precisely-controlled environment, a high energy particle accelerator such as the Large Hadron Collider in Switzerland, or in outer space, because high-energy collisions can be measured more easily there.
The graph above shows an increase in the fraction of positrons, a sort of anti-electron that many think of as sign of dark matter. According to scientists, the data showed no significant variation in time or direction. This would make it consistent with the constant background annihilation of dark matter in space. In their words, "a significant portion of the high energy electrons and positrons originate from a common source."
Of course, a single piece of evidence is far from a theory confirmed. There are other cosmic phenomena that would explain the high amounts of high-energy particles. The possible alternative explanations include pulsars, highly compressed stars that ring the edge of the Milky Way galaxy.
Concerning the AMS itself, the flight to launch it to the stars was nearly threatened when it happened, taking an act of Congress during the last term of the George W. Bush administration in 2008. The AMS was sent up in 2011 on the second to last space shuttle flight before the entire fleet was retired.
Although hailed as the proof of dark matter in many media outlets, the data represents just the first two years of what could be a 10-year voyage. If the next few years are as productive as the first two, the AMS could have much more to tell us in the future.