Updated: After the launch attempt on Wednesday had to be scrubbed due to weather, SpaceX and NASA have successfully launched a truly historic mission.

At 3:22 pm ET on 30 May 2020, SpaceX became the first private space company to deliver NASA astronauts to the International Space Station (ISS).

This marks the first time since the 2011 end of the Space Shuttle program that American spacecraft has carried NASA astronauts into orbit, and on to the ISS.

You can watch the SpaceX livestream here:

LIVE BLOG (all timestamps ET/refresh to see the latest):

The final launch preparations for the Demo-2 mission are currently taking place at Cape Canaveral, Florida, and we're here to bring you a live blog of the final countdown and the launch as it happens - weather pending!

The two astronauts already strapped in aboard the Crew Dragon are Bob Behnken and Doug Hurley, both veteran spacefarers with several missions under their belts. For the second time this week, they have donned the new spacesuits and are patiently waiting as the teams go through the final preparations.

2:20 pm: Ahh, feels like deja vu to be here again for that final hour of launch preparations. We're sure we're not alone.

2:22 pm: T minus one hour! The team is go for the final checks.

2:23 pm: The crew is go for launch. We've been watching a re-run of Bob and Doug going through the crew ingress process. Those spacesuits really look spectacular.

"The old spacesuits are really heavy," Hurley said in 2018. "SpaceX started from scratch and built this in-house. It's pretty neat-looking. I've worn the suit over 20 times already, and it's lighter and a lot more comfortable to wear."

2:29 pm: "It's starting to feel real."

2:32 pm: Leland D. Melvin, retired NASA astronaut and space engineer who has logged over 565 hours in space, is part of a commentary panel at Kennedy Space Center in this livestream, and he's reminiscing how surreal it felt to put on a spacesuit for the first time. "It took me 10 years of training to go to space."

2:33 pm: It's go for weather! For now… trying not to get our hopes up, but things are looking hopeful! (Also, we just noticed we've been labelling the timestamps in Australian time. It's 4 am here, bear with us.)

2:36 pm: Launch director Mike Taylor just announced an early call of "go for propellant load", and the crew arm is ready to retract! There's a 70 percent chance of good weather, which is already much better than what we were experiencing on Wednesday.

2:38 pm: We're hearing the safety briefing. If anything were to go wrong, the Crew Dragon has a unique emergency abort system you can read more about here.

2:39 pm: Green across all weather conditions! They have to be monitored until the last minute, but!

2:42 pm: The crew access arm has retracted. As you might remember from Wednesday, the next crucial step is propellant load into Falcon 9, the rocket carrying the Crew Dragon capsule.

There are two substances being loaded in this stage - densified liquid oxygen and RP-1 kerosene. Those two won't ignite on their own - the rocket uses the addition of a third fluid known as TEA-TEB (triethylaluminium-triethylborane) to ignite the engines. TEA-TEB catches fire spontaneously when it comes into contact with oxygen, this is known as a pyrophoric substance.

2:52 pm: Propellant load is happening. You can see a puff of white on the body of the rocket, where the liquid oxygen is off-gassing.

2:53 pm: Weather is still looking good. The instantaneous launch window is at 3:22 pm ET.

2:56 pm: We're hearing an explanation of how Crew Dragon will dock with the ISS, spend up to 100 days up there, and then return with a splashdown in the ocean. The weather still looks clear.

2:57 pm: "This will mark a new era when more people than ever before will be able to go to space."

3:00 pm: SpaceX engineer Lauren Lyons is talking about how Bob and Doug are just "good people", and around the office are referred to as "the dads". "We're so excited to see the dads up there today!"

3:02 pm: T minus 20 minutes! The giant white cloud might look alarming, but it's perfectly normal - the humid Florida air is turning that off-gassing liquid oxygen into a pretty little cloud. WEATHER CONTINUES TO BE GO.

3:04 pm: SpaceX principal integration engineer John Insprucker is starting to sound pretty excited as he gives continuous updates on mission status.

3:05 pm: Experts on the livestream are now starting to cautiously talk about how the spaceflight will actually occur. It will take 9 minutes to reach orbit, and it will be a 19-hour ride to the ISS.

Liquid oxygen is now being pumped into stage two of Falcon 9. On Wednesday, at this point weather conditions forced the launch to be scrubbed… so the countdown is going better. At T minus 7 minutes we can expect to hear an update about the weather downrange, and any lightning risks.

3:10 pm: T minus 12 minutes… "We want to hear 'nominal' as much as possible on the way uphill."

3:14 pm: What's next? At T minus 7 minutes Falcon 9 begins engine chill - allowing small amounts of the cryogenic propellants into the engine system to bring the temperature down.

3:17 pm: We're so, so close.

3:19 pm: "Dragon has transitioned to terminal count and is now on internal power."

3:21 pm: GO FOR LAUNCH! "Let's light this candle."

3:22 pm: LIFTOFF!

3:23 pm: "Look at them go!" John Insprucker exclaims as the Falcon 9 rockets off into the sky. We're hearing lots of 'nominal' assessments so that's good.

3:25 pm: The first stage of Falcon 9 has successfully separated. There's lots of cheering on the livestream. Stage two of Falcon 9 is powered by a single Merlin engine. Still about 6 minutes before the astronauts reach orbit.

3:28 pm: As Bob and Doug continue to gain speed - the counter on the screen sits at 13,000 km/h and rising fast - the first stage of Falcon 9 is attempting to return to the landing ship at sea. That's a lot to take in all at once!

3:31 pm: The two astronauts are currently experiencing the highest Gs in their travels. And we have confirmation of second engine cutoff. Everything is still looking fantastic!

3:32 pm: Falcon 9 just successfully landed on Of Course I Still Love You drone ship! That's right, we get to keep the rocket that just launched the two humans into space.

3:33 pm: Bob and Doug just whipped out some sort of sparkly… balloon? Nobody on the livestream knows what that was. [Okay, so it was a purple foil dinosaur balloon floating off, showing the microgravity at work.]

The two astronauts are already 200 kilometres or 124 miles above Earth.

3:35 pm: Dragon separation confirmed!!!!!!!!!!

3:37 pm: Falcon 9's job is done for today, but the mission is not over. Tomorrow morning, Bob and Doug will be docking with the ISS. The astronauts will get around eight hours of sleep later today, before they arrive at the space station. Live coverage will continue the entire way.

3:39 pm: "A day for the history books."

3:46 pm: Well, that's all for the live blog, folks! As we mentioned, the livestream coverage will continue all the way through to Bob and Doug's arrival at the ISS.