Today (July 9) is the long-delayed launch of Europe’s new heavy-lift rocket, the Ariane 6. If all goes as planned, the Ariane 6 will lift off from Europe’s spaceport in Kourou, French Guiana, on a four-hour flight on Tuesday. The window opens at 2 p.m. EDT (18:00 GMT).

You can watch the launch live on Space.com, courtesy of the European Space Agency (ESA); coverage will begin 30 minutes before kickoff. Operated by France’s Arianespace on behalf of ESA, Ariane 6 will replace the venerable Ariane 5, which was retired last year after 117 flights over nearly three decades.

The Ariane 6 has been in development for nearly a decade. It was initially scheduled to launch in 2020, but technical issues and external concerns like the COVID-19 pandemic and Russia’s ongoing invasion of Ukraine have pushed back the timeline several times. Europe has high hopes for the new launch vehicle, which is expected to make nine to 12 flights per year through 2026.

In a preview of the first launch, ESA officials wrote that Ariane 6 “will deliver our assured autonomous access to space and all the science, Earth observation, technology development and commercial opportunities that this entails.”

“With many completely new features on Ariane 6, we will be able to carry more and carry it farther, while also protecting the upper part of the launcher from becoming space junk without harming the environment,” they added.

If all goes as planned, Ariane 6 will deliver nine cubesats into low Earth orbit (LEO) during its flight on Tuesday. The rocket will also carry out a variety of out-of-orbit experiments, including two capsules that will be fire-tested as it returns to our planet through its thick atmosphere.

As ESA noted in a previous mission review, the rocket’s upper stage will also return to Earth, but the top section will not survive the journey and will instead burn up in our air.