Today marks 50 years since Apollo 11 landed on the surface of the Moon – the first manned craft to do so. To mark the historic moment, I’m writing a series dedicated to Apollo 11, with this part looking in detail at the landing and how Neil Armstrong and Buzz Aldrin almost faced disaster – twice.

The Eagle preparing to land
Image: NASA

At 17:44 UTC, the ‘Eagle’ (codename given for the Lunar Module) separated from the Command Module (dubbed ‘Columbia’) – with Armstrong proclaiming ‘The Eagle has wings!’ He, along with Aldrin, began the descent to the lunar surface, while Collins remained in Columbia awaiting their return.

The descent soon ran into some difficulty, however, when the two astronauts realised they were travelling too fast. As a burn was carried out, the guidance computer began showing alarms which indicated it was overloaded. Mission Control back on Earth decided that this posed no threat, and descent continued as planned.

Armstrong noticed that the landing site the computer was directing the Lunar Module to was strewn with boulders, so to avoid this area, he took control of piloting the Eagle to the lunar surface. Armstrong looked for level ground to land, but the craft’s propellant was dwindling.

After finding what he thought was a suitable site, closer inspection revealed it had a crater in it. Once the crater was cleared, Armstrong found a suitable landing site, with just 90 seconds of fuel spare.

As the two men tried to land the craft, dust from the engine began to obscure their ability to determine their motion. Thankfully, some rocks were peaking out from the dust cloud, giving the crew something to focus on as they made their final descent.

As a light indicated one of the probes hanging from the footpads of the Lunar Module had touched the surface, Aldrin said ‘Contact light’. Three seconds later, Armstrong shut down the engine and the craft had safely landed on the surface of the Moon.

At Mission Control, Capsule Commander Charlie Duke acknowledged the landing, saying ‘We copy you down, Eagle.’ Armstrong replied with the immortal words ‘Houston, Tranquillity Base here, the Eagle has landed.’