Artemis II: Day Four

Destination in Sight

It won’t be long until the crew of Artemis II become the first humans to enter the Moon’s sphere of influence in 54 years - this is the area in which the Moon’s gravity is exerts more of a pull on the spacecraft than that of Earth. By any reasonable definition they will have reached the Moon at this point.

The Moon is now quite large in the window, and the crew have already begun visual observations of it.

At the current distance of the spacecraft, around 366,000 km at the time of writing, there is notable lag in radio communications due to the speed of light. Another way to write their distance would be as 1.2 light seconds, so a round trip signal to them takes 2.4 seconds. You may notice in live conversations with the crew this delay in their response.

Approaching the Moon

I’ve now plotted the Moon on the orbit diagram; it will pass through the centre of the loop when Artemis II is at the very bottom of the orbit as shown. It might not seem as if the two objects will intersect, but bear in mind that Integrity is slowing down significantly at this point.