Update March 30th, 5:00PM ET: There’s still an 80 percent chance at favorable weather for tonight’s launch, according a mid-day update from the US Air Force.

Elon Musk’s private spaceflight company is going to take another swing at history today: for the first time, SpaceX plans to take a Falcon 9 rocket that successfully launched and landed in April 2016 and try to launch it to space once again. The launch window opens at 6:27PM ET and runs until 8:57PM ET, and SpaceX will live stream the attempt on its YouTube channel. The hosted webcast is embedded above, and a technical webcast (with no narration) can be seen below. Coverage should start about 20 minutes before liftoff.

SpaceX has spent the last year carefully evaluating and refurbishing this particular Falcon 9. In total, the company has landed eight rockets in 13 attempts since December 2015. Should the launch go off without a hitch, the company will also attempt to land the rocket on a drone ship in the ocean for the second time. If the landing is successful, SpaceX will most likely try to refurbish the rocket again in order to try and launch it a third time.

Successful relaunches means SpaceX could lower the cost of getting to space

Ideally, this is a proof-of-concept for reusing rockets, one of Elon Musk’s main goals for SpaceX. By recovering each rocket after launch instead of discarding it, Musk hopes to cut the cost of a rocket launch by millions of dollars. This could eventually allow SpaceX to offer launches at a 30 percent discount, which is a huge advantage in the tiny but hyper-competitive space launch market.

SpaceX isn’t the only company working on reusability. Amazon founder Jeff Bezos’ space company Blue Origin has successfully launched, landed, and relaunched the same New Shepard vehicle multiple times. The two companies are after different short-term goals, though — Blue Origin is working toward offering space tourism rides to the boundary of space in while SpaceX already has paying customers who need a ride to much higher heights.

Speaking of those customers, today’s relaunch and potential landing is still technically the sideshow. SpaceX’s mission is to send the SES-10 communications satellite to space for Luxembourg-based company SES. The rocket’s second stage will help complete that mission after the Falcon 9’s first stage separates and heads back to Earth. Once it’s been released from the rocket, the SES-10 will eventually park itself in what’s known as geostationary orbit, a spot 22,000 miles above the Earth. There, it will stay locked with the planet’s rotation and improve communications for Latin America.

As of this morning there’s an 80 percent chance that the weather conditions will be favorable for the launch. Our own Loren Grush is in Cape Canaveral to cover the event, which will take place at Launch Complex 39A — the same launchpad where the famous Apollo 11 mission began in 1969.