Alex McColgan

As they left the planet behind,

Orion transitioned to a new era of deep space communications.

Alongside the traditional S-band radio of the deep space network, which has been the backbone of spaceflight since Apollo, Artemis II debuted a game changer, the O2O, or Orion Artemis II Optical Communications Terminal.

The system uses near-infrared laser light at a wavelength of 1,550 nanometers.

Unlike radio waves, which spread out significantly over long distances, these lasers remain tightly focused, allowing for a 30-fold increase in data density.

At its peak, O2O downloaded data at 260 megabytes per second, enough to stream high-definition 4K video from around the moon, all the way back to ground stations in New Mexico and California.

By day 4, the O2O terminal had transmitted more than 100GB of data.

Among these files was the already infamous Hello World photo.

Captured by Commander Wiseman through Integrity's window, it shows Earth as a dark sphere, lit only by a thin, razor-sharp rim of light as it eclipses the sun.

To capture the faint details of the Earth's night side, Wiseman had to push his Nikon D5 camera to a staggering ISO of 51,200 with a quarter-second shutter speed.

The camera is so sensitive that it also saw something the human eye could only dream of, the ethereal green glow of the auroras shimmering at the poles.

and the planet Venus has a bright silver glint in the corner of the frame.

You can even see our atmosphere, with air glow from excited sodium atoms lighting up its very edge, and the zodiacal light from space dust reflecting sunlight, a phenomenon usually seen only in the darkest skies on Earth.

This, to my mind, is one of the most beautiful images ever captured by a human hand, and it was the first of many as the mission progressed.

But while the view from the window of integrity was spectacular, it was what the crew couldn't see that posed a great threat.

As Integrity left the protective magnetic umbrella of Earth, the crew faced the invisible hazard of deep space, radiation.

Radiation beyond Earth's orbit is up to 100 times more powerful than what we experience on the ground, consisting of galactic cosmic rays and solar particle events.

To track this, Orion was equipped with six hybrid electronic radiation assessors,

and four specialized detectors called M42EXTs, which featured six times the resolution of previous models to distinguish between hazardous heavy ions and protons.

But why did they want to track it with such precision?