After years of anticipation and a number of delays, SpaceX successfully fired all 27 engines on its Falcon Heavy rocket Wednesday—marking a necessary step ahead of the vehicle’s inaugural voyage in the upcoming weeks.

The fire test was conducted at 12:30 p.m. ET at the Kennedy Space Center in Florida. According to CBS News, the firing lasted a little more than 10 seconds and produced a deafening roar as well as a large plume of steam that had witnesses in awe.

SpaceX has yet to release any information about the rocket’s performance during the test; however, the company’s founder, Elon Musk, tweeted Wednesday that the firing “was good,” and that he expects the rocket to launch in the next “week or so.”

The static fire test is intended to evaluate the rocket’s engines prior to its maiden flight. The spacecraft is placed on a launching pad and fired up without actually leaving the ground. Though these kinds of inspections are pretty standard for the company, this test was particularly notable because it marked the first time SpaceX was able to ignite this many engines simultaneously.

But the show is far from over.

If all goes according to plan, the Falcon Heavy will become the world’s most powerful operational rocket to ever successfully launch. The vehicle is basically three Falcon 9 rockets bonded together and can generate over 5 million pounds of thrust at liftoff; SpaceX claims that is equal to about 18 747 aircraft. However, as CBS points out, Musk isn’t letting his expectations get too high.  

“There's a lot of risk associated with Falcon Heavy, a real good chance that that vehicle does not make it to orbit,” he said in 2017. “I want to make sure to set expectations accordingly. I hope it makes it far enough beyond the pad so that it does not cause pad damage. I would consider even that a win, to be honest.”