But Musk’s success has brought increasing scrutiny from federal regulators, who are weighing the risk SpaceX and other rapidly advancing commercial space operations pose to the environment and the general public against the desire to return the U.S. space program to its past glory.

“These are not only the largest rockets known to mankind but they tend to explode,” said Jared Margolis, an attorney with the Center for Biological Diversity, part a coalition of environmental groups suing the Federal Aviation Administration to block SpaceX launches. “And they’re launching next to a very environmentally sensitive area with no buffer around the launch site.”