Some Moon missions that ended up in a crash were a success! We’re talking about the NASA Ranger missions.

The Ranger spacecraft sent by NASA to intentionally crash onto the Moon! Credit: NASA

Before the time of the famous Apollo Moon landings in 1969-72, scientists didn’t know what the Moon was like up close. To ensure that astronauts could land safely, it was important to know what kind of local terrain the Moon hosts and map hazards on it to avoid.

Back then, the only way to capture images of the Moon was with big telescopes on Earth, which couldn’t discern much. Post the advent of the space age, images of the Moon’s surface captured from orbit wouldn’t be as high-res as they’re today. To truly determine what the local lunar surface was like, NASA had to send spacecraft smashing into the lunar surface! And thus the Ranger program was born. Not Power Rangers, mind.

Each craft in the Ranger program was equipped with a TV camera setup to send images to Earth in near real time while descending towards the Moon.

Ranger spacecraft diagram. Credit: NASA

The resolution of images the Rangers could capture was be 100 to 1,000 times higher than any other method at the time. It is only now that NASA’s Lunar Reconnaissance Orbiter can image areas at a best resolution of 0.5 m/pixel from orbit. ISRO’s newly put lunar orbiter, Chandrayaan 2, can do a best of 0.3 m/pixel.

When the first such successful mission of the Ranger Program, Ranger 7, took the fall in 1964, everyone was surprised. Vast plains on the Moon which looked welcoming turned out to marked with craters all over when inspected up close.

Photographs sent by NASA’s Ranger 7 spacecraft 90 seconds before smashing into the Moon. The top two images are about 15 km across and the bottom ones 5.5 km across. Credit: NASA

The Ranger missions revealed the Moon to be a land of craters more than anything else, at scales large or small. Here’s a video made from Ranger 7’s camera shots, capturing images starting from 2000 kilometers above the Moon’s surface down to just 500 meters, after which the craft crashes.

NASA Ranger 7 descending towards the Moon. It’s craters all the way down! Image credits: NASA

The Ranger 8 and 9 missions all but confirmed that the Moon is riddled with craters. In all, the Ranger missions sent over 15,000 high-resolution photographs to Earth. It is from this data that NASA selected safe landing regions for the Apollo missions. The robotic Ranger missions were thus critical for NASA to safely land humans on the Moon in 1969.

The NASA Ranger missions were literally and figuratively a smashing success!

Heck, closeup images of rock samples brought back from Apollo missions revealed that the Moon is cratered even at microscopic scales!

Comparison of micro-sized lunar crater with a small tardigrade and a human hair strand. Image sources: 1, 2.

It’s craters all the way down.