"From the landing site, Snoopy sends the word"
—(LIFE, 6 June 1969, pg. 30B)
A major objective of the Apollo 10 crew was to describe and photograph with the 250mm telephoto lens the tracking landmarks leading to Tranquility Base – designated as landing site 2 at the time – where the Apollo 11 astronauts landed two months later. These two photographs were taken successively as the spacecraft was flying westward over the future Apollo 11 landing site on orbit 18.
The first photograph is a superbly detailed photograph of the Moon’s surface near Tranquility Base. The photograph was taken from the CSM Charlie Brown shows the 6-km Crater Maskelyne G and “Diamondback Rille” branching off into a fork at the right (2.5° N / 27° E ) in the immediate area preceding Tranquility Base to the east.
From the LM Snoopy, Stafford and Cernan were so temptingly close they felt they could reach out and touch every boulder. They saw _ and the Command Module overhead photographed _ the Moon as man had never seen it. The photograph shows landmarks that will guide crewmen of Apollo 11 in their attempt to land on the Moon this summer: in particular, the deep rille called ”Diamondback.” (LIFE, 6 June 1969, pg. 30B)
The second photograph shows Tranquility Base (Apollo landing site 2), photographed for the first time by humans from lunar orbit. The great detail confirmed that this area of the Moon was suitable for the first Moon landing in the history of humankind.
From the mission transcript when the photographs were taken:
And we’ve got the Sidewinder Rille over on the right. We’ve got - here’s Diamondback on the right, Sidewinder’s on the left, and this whole chain of craters leading up to site 2. And, again, if you didn’t hear me, down below, there, it doesn’t look near as rough and as rugged out here in the mare areas as it does in the other parts. It’s pretty well chained up.