Launch day arrives for NASA's Artemis I mission that will journey around the moon

Weather conditions remain 80% favorable for a launch at the beginning of a window that opens at 8:33 a.m. and closes at 10:33 a.m. ET, according to the latest forecast.

However, offshore storms with the potential for lightning prevented the team from beginning the fueling process, due to start at midnight, for more than an hour.

The hold was lifted at 1:13 a.m. ET, and the tanking process has begun.

The rocket's core stage will be loaded with supercold liquid oxygen and liquid hydrogen over the next several hours.

Currently, engineers are also working to find out what has caused an 11-minute delay in communications between the Orion spacecraft and ground systems. The issue could impact the beginning of terminal count, or the countdown that begins when 10 minutes remain on the clock before liftoff. But engineers feel good about figuring out the issue ahead of the terminal count, according to NASA.

Mission overview

Orion's journey will last 42 days as it travels to the moon, loops around it and returns to Earth -- traveling a total of 1.3 million miles (2.1 million kilometers). The capsule will splash down in the Pacific Ocean off the coast of San Diego on October 10.

While the passenger list doesn't include any humans, it does have passengers: three mannequins and a plush Snoopy toy will ride in Orion.

The crew aboard Artemis I may sound a little unusual, but they each serve a purpose. Snoopy will serve as the zero gravity indicator -- meaning that he will begin to float inside the capsule once it reaches the space environment.

The mannequins, named Commander Moonkin Campos, Helga and Zohar, will measure deep space radiation future crews could experience and test a new suit and shielding technology. A biology experiment carrying seeds, algae, fungi and yeast is tucked inside Orion to measure how life reacts to this radiation as well.

Cameras inside and outside of Orion will share images and video throughout the mission, including live views from the Callisto experiment, which will capture a stream of Commander Moonikin Campos sitting in the commander's seat. If you have an Amazon Alexa-enabled device, you can ask it about the mission's location each day.

Expect to see views of Earthrise, similar to what was shared during Apollo 8 for the first time, but with much better cameras and technology.

Science experiments and technology demonstrations are riding in a ring on the rocket. The 10 small satellites, called CubeSats, will detach and go their separate ways to collect information on the moon and the deep space environment.

The inaugural mission of the Artemis program will kick off a phase of space exploration that lands diverse astronaut crews at previously unexplored regions of the moon and eventually delivers crewed missions to Mars.

The rocket and spacecraft will be tested and put through their paces for the very first time before they carry astronauts to the moon on Artemis II and Artemis III, slated for 2024 and 2025 respectively.