Way back in 2006, a group of scientists inflated a giant balloon intended to float over Antarctica. Kitted out with sophisticated equipment, the inflatable was launched in order to detect high-energy particles arriving on Earth from space. While it was in the air, though, the balloon observed something peculiar. And now the scientific consensus of the past century or so is being called into question.
Antarctica – the most southerly continent on planet Earth – was initially sighted in 1820 by a Russian naval expedition. The first landing on Antarctica, however, is not thought to have taken place until January 1895, when a pair of Norwegian adventurers finally arrived at Cape Adare, to the north of the continent.
And as the majority of Antarctica is coated with thick ice, human exploration there has proven difficult since its discovery. Still, given the unique conditions found on the continent, it’s naturally of great interest to the global scientific community. In order to aid scientific investigation there, then, the Antarctic Treaty System began to be enforced in 1961.
The Antarctic Treaty System is an understanding between nations to support scientific interest in the continent and ensure peace there. Today there are 53 signatories to the treaty, though initially there were only 12. Among the dozen countries to first agree to the system were the United States and the Soviet Union; interestingly, the treaty then served as the inaugural arms-control pact made during the period of the Cold War.
And thanks to the Antarctic Treaty System, researchers from all over the world come to Antarctica to carry out experiments. These groups include people from many different fields, including those with knowledge in astronomy, biology and physics. What’s more, given the breadth of investigation undergone in Antarctica, many vital discoveries have been made there over the years.
For example, in 1985 researchers focused on Antarctica discovered a hole in the ozone layer. The alarming feature was eventually ascertained to have been created through use of chlorofluorocarbons (CFCs). And in 1989 this crucial discovery led to the Montreal Protocol, which saw CFCs being phased out worldwide – a move that has led to the gradual renewal of the ozone layer.
That said, less publicized discoveries have been made in the continent for decades. In 2006, then, when scientists witnessed something new, that they had made a find wasn’t surprising in and of itself. What is significant, though, is that the consequences of the research may call for an overhaul of established scientific thought.
In December 2006 the big balloon – launched as part of the Antarctic Impulsive Transient Antenna (ANITA) experiment – was sent into the air by experts associated with NASA. Rigged with specialized equipment, the ANITA balloon floated for a month above Antarctica at a height of around 120,000 feet. Its purpose was to identify so-called “cosmic rays” that emanate from space and eventually land on Earth.
Cosmic rays – or highly energetic particles – are known to move throughout space at somewhere near the speed of light. Yet while scientists have been aware of this form of radiation for some time, the ANITA experiment seemingly identified something unusual: some rays, it appeared, were coming up from the ground itself. This in turn suggested that the particles were actually traveling from one end of the planet to the other.
Furthermore, successive ANITA experiments in 2009 and 2014 have presented similar results. And while experts haven’t ascertained where the rays are coming from, theories as to their origin have been posited. Many of these hypotheses, however, do not have a place within the Standard Model of particle physics.
The Standard Model of particle physics was developed during the 20th century thanks to the efforts of multiple scientists worldwide. Now, it represents the most precise theory ever devised for explaining how fundamental particles interrelate. And so, given this importance to scientific knowledge, the ANITA discovery might well prove to be a revelation.
Then in September 2018 scientists presented a paper theorizing that the cosmic rays coming from the ground are evidence of what has been termed a “supersymmetric particle” – one with a partner. If this is the case, it would be the first time that proof of such a particle has been found.
In addition, while supersymmetric particles wouldn’t make the Standard Model redundant, they would call for a reexamination of that theory. The Standard Model would need to be expanded, too, in order to consider this new category of particle. Derek Fox, the lead researcher of the paper, attempted to break down the Antarctica findings to Vice’s Motherboard website.
“We argue that if the ANITA events are correctly interpreted, then they require some beyond the Standard Model particle,” Fox explained to Motherboard in September 2018. “The likely properties of the particle seem consistent in at least some ways with the predicted properties… in some supersymmetric models.”
To back up their hypothesis, Fox and his team had to illustrate that the phenomenon recorded by the ANITA experiment is unlikely to occur under the Standard Model. Specifically, they argued that the paths of the cosmic rays could not be explained through the long-standing theory. But, understandably, these arguments haven’t been taken on board by everyone in the scientific community.
For instance, The Ohio State University associate professor Amy Connolly, who has also helped produce research into the matter, has urged against making any hasty judgments. As she and her colleagues see it, the events observed by ANITA certainly open up encouraging lines of investigation; they do not, however, necessarily point to a new way of understanding physics.
“Any time an experiment has observed only two events of interest, there is a possibility that, as more data is taken, the anomalous events may be found to be a background not previously anticipated,” Connolly told Motherboard. “Although it is exciting that ANITA can be sensitive to beyond-the-Standard-Model physics, we must exercise caution and carry on assuming that the most likely possibility is that these events are an as-yet-unexplained background.”
In fact, even Fox himself is unwilling to overstate the significance of the cosmic rays discovered through the ANITA experiment. The theory can only gain credence among the wider scientific community when similar phenomena have been observed in multiple locations; as a result, then, Fox and his team set out to do just that.
To begin with, Fox and his fellow researchers looked at what was going on in the Arctic. And, interestingly, by examining data obtained by the IceCube Neutrino Observatory, the team did in fact identify three events comparable to those detected by the ANITA experiment. It’s hoped that there are yet more such examples to be uncovered within findings made at IceCube.
The Fox-led scientists may even have more evidence of the unusual cosmic rays to come, as data from a 2016 ANITA mission is now being analyzed. And even if the information gleaned by way of that scrutiny does not ultimately reshape particle physics, the possibility of it doing so is nevertheless a tantalizing one.