Update July 25th, 9:25AM ET: Both rockets successfully launched on time this morning. While the Ariane 5 launch is still ongoing, SpaceX’s Falcon 9 completed its mission in a little over an hour. The rocket’s booster managed to land on the company’s drone ship in the Pacific, despite poor weather conditions at the site. There was some confusion at first about whether it survived, thanks to bad lighting on the boat, but SpaceX later got visual confirmation that the booster touched down successfully. Additionally, SpaceX was not able to catch its rocket’s nose cone. The company’s recovery boat, Mr. Steven, saw the structure falling from the sky but was unable to catch it.

Original Story: Early Wednesday morning, rocket enthusiasts will have the lucky experience of being able to watch two launches at roughly the same time. Around 7:30AM ET, SpaceX is slated to launch one of its Falcon 9 rockets from the California coast, while European launch provider Arianespace will send up its Ariane 5 rocket from its South American spaceport in French Guiana. If all goes according to plan, the vehicles will launch around 15 minutes apart.

Here’s what’s going up (and down) tomorrow

The two rockets will be traveling in very different directions, though. The Ariane 5 will be launching to the east over the Atlantic Ocean, while SpaceX’s Falcon 9 will be launching to the south in the Pacific. But thanks to live-streaming, viewers will be able to see the two missions back-to-back on their screens. Of course, that will only happen if the weather is good in both locations, there are no problems with the rockets, and no wayward boats or planes get in the way.

Here’s what’s going up (and down) tomorrow and where to watch these flights.

SpaceX

Tomorrow’s SpaceX launch will be the seventh mission the company does for long-standing customer Iridium. SpaceX has a contract with Iridium to launch 75 satellites for the company’s Iridium NEXT constellation, which provides global telecommunications coverage. SpaceX has been launching these probes in batches of 10 (except for the sixth mission, which sent up five satellites). After this seventh flight, SpaceX only has one more group of satellites to launch, and then its job for Iridium will be complete.

SpaceX’s Falcon 9 is slated to take off from Vandenberg Air Force Base in Southern California at 7:39AM ET. Following launch, SpaceX hopes to recover as much of the rocket as it possibly can right now. The rocket booster will attempt one of the company’s signature landings on a SpaceX drone ship in the Pacific Ocean. And a little while afterward, SpaceX will also try to catch the Falcon 9’s nose cone, or payload fairing, the bulbous structure that surrounds the satellites at the top of the rocket.

SpaceX has been trying to catch its rockets’ fairings for months now, but it hasn’t been able to snag one out of the sky yet. To recover these structures, the company has equipped them with parachutes to help slow their fall down to Earth. Then, once they get close to the ocean’s surface, SpaceX tries to catch them with a huge net attached to a boat called Mr. Steven. SpaceX just recently expanded the net on Mr. Steven, making it four times its original size. We’ll see if that does the trick for this flight, though this is also the first time that SpaceX will try to catch a fairing at night.

No matter what, this all should make for a dramatic mission tomorrow, and Iridium has the perfect thing to make the experience even more interesting: a launch playlist. Iridium curated a Spotify soundtrack that is meant to “reflect what viewers of the SpaceX webcast are watching or are in some way related to the Iridium story (including metaphorically),” according to the company. Just log in to Spotify, select the Iridium-7 Launch Soundtrack from the playlists, and hit play when the countdown timer is at 10 minutes and 30 seconds. The songs are all pretty on point, too, like “Intergalactic” from the Beastie Boys and “I Want to Break Free” from Queen.

Arianespace

Arianespace’s Ariane 5 is expected to take off at 7:25AM ET, around 14 minutes before SpaceX flies. This is the fourth launch of an Ariane 5 this year, and the rocket will carry four satellites into orbit. They’ll join 22 similar ones already in space that make up the Galileo constellation, which provides global navigation services for Europe.

This mission also marks the final launch of a version of the rocket called the Ariane 5 ES. It’s a variant that’s been used to launch Galileo satellites before. But after this flight, all future Galileo satellites will be launched on Arianespace’s next rocket, the Ariane 6, which is currently in development. The first flight of that vehicle is slated to take place in 2020.

The European Space Agency’s coverage of the Ariane 5 flight is set to begin at 7AM ET, while SpaceX’s coverage of the Iridium launch will begin 15 to 20 minutes before liftoff. Check back in the morning to get a double dose of live rocket launches on your computer screen.