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In late June a 21-year-old named Mathew Roberts created a public Facebook event titled "Storm Area 51, They Can't Stop All of Us." What started off as a joke become a phenomenon, with over 2 million hitting the "going" button. The initially tongue-in-cheek event turned into a real festival, now called Alienstock. The original event even has its own Wikipedia page.

Alienstock is planned to be an alien festival in Rachel, Nevada on Sept. 20. However, according to Fox 5, Roberts has pulled out of the event. Connie West, who owns the Little A'Le'Inn Motel the event is based at, told the publication Roberts had backed out out of concern over permits and logistics.

In a separate interview with ABC Arizona, Roberts said he was worried the event would end up being "a disaster." His co-organizer Frank DiMaggio added: "We don't have a good feeling about people going out 150 miles into the desert without the resources that they need."

It's something of a 180 for Roberts, who less than 24 hours earlier told Fox 5 that the event is happening "no matter what." Alienstock is set to feature at least 20 bands and two comedians, and West told the publication that the event will still go on even without Roberts, West told Fox.

It's not the first bump in the road for Alienstock. On Aug. 3 Roberts' "Storm Area 51" page was taken down by Facebook for violating community standards. "I never got any reason behind the event being removed," Roberts told CNET at the time, but Facebook revived the page days later. Even the US Air Force chimed in, strongly encouraging people to not go anywhere near Area 51.

Area 51 is a highly classified zone around 150 miles from Las Vegas, Nevada, a detachment of the famed Edwards Air Force Base. No one really knows what the base is used for, though it's speculated to be a location for aircraft development and, as such, Area 51 has become synonymous with alien conspiracies. The most popular ones involve alien spaceships or aliens themselves, all allegedly housed within the classified zone.