If you haven’t already heard, Virgin Orbit successfully dropped a 70-foot rocket from a modified Boeing 747 jumbo jet at 35,000 feet. Although that sounds more like a dreadful occurrence that would happen during a war, it’s actually a good thing. Here’s why.

Currently, launching a satellite into orbit from the ground requires a massive amount of rocket fuel, not to mention a lot of money. By launching a rocket from a height of 35,000 feet, which is a typical cruising altitude for commercial planes, far less fuel needs to be used— sparing the environment a bit.

During the recent test, Virgin Orbit, which is a Richard Branson-backed space startup, did not actually launch the rocket once it detached from the wing of the modified 747. Instead, it fell 35,000 feet to the ground, where it impacted in a planned drop zone at Edward’s Air Force Base in the Mojave desert. Later this year, Virgin Orbit plans to test its first actual orbital test rocket launch.