An ordinary felt-tip pen that helped save two astronauts from being stranded on the Moon has been sold at auction for $857,600.During the historic Apollo 11 mission in July 1969, Buzz Aldrin used the simple writing tool to fix a broken circuit breaker, allowing the lunar module to leave the Moon and return safely to Earth. The brushed aluminium Duro Rocket pen was the highlight of Sotheby’s 2026 Space Exploration auction, where it sold within its expected price range of $800,000 to $1.2 million.The pen was sold directly from the Buzz Aldrin Family Trust and remains one of the most famous examples of emergency problem-solving in space history.
The broken switch on the Moon
The story of the pen began after a dangerous problem inside the Lunar Module Eagle. After Neil Armstrong and Buzz Aldrin finished their historic Moonwalk, they returned to the lander to prepare for departure. That was when they found a serious issue.Inside the small spacecraft, one astronaut had accidentally broken the plastic tip of the Engine Arm circuit breaker switch. This switch was extremely important because it activated the ascent engine, the only engine that could lift the upper part of the Eagle from the lunar surface.Without the switch, the engine could not start. This meant Armstrong and Aldrin could have been left permanently on the Moon, while Command Module pilot Michael Collins continued orbiting alone in Columbia, unable to help them return.
The pen is a brushed aluminum Duro “Rocket” black felt-tip pen measuring approximately 5.5 inches in length.
A simple solution in space
With time running out, Aldrin searched for a way to solve the problem. He noticed that the broken switch had left a small opening where the plastic part had been. If he could insert something small enough, he could press the internal metal contact and activate the circuit.A metal object such as a screwdriver or key could have caused a short circuit and damaged the spacecraft’s electrical system.Aldrin then remembered his Duro Rocket pen. The pen’s black plastic tip did not conduct electricity, making it safe to use. He placed the tip into the broken circuit breaker opening and pushed it down. The switch moved into position, and the system was successfully activated.The repair worked. On 21 July 1969, the ascent engine fired as planned, allowing the Eagle to lift off from the Moon and meet Collins in lunar orbit.
The small tool that became a historic artifact
The pen is about 5.5 inches long and is a standard brushed aluminium writing instrument. Its cap has a pocket clip marked with the word “Rocket” and a small Velcro strip that helped astronauts attach it to the spacecraft walls in zero gravity.Sotheby’s sold the pen along with the broken Engine Arm circuit breaker switch button that caused the emergency. Both items came with a signed letter of authenticity from Aldrin, confirming that they were flown to and used on the Moon.The auction also featured other important space artifacts, including Aldrin’s personal Omega Speedmaster watches, Apollo mission equipment, and rare engineering items from both the American and Soviet space programmes.
The legacy of Apollo 11
NASA launched the Apollo 11 mission on 16 July 1969 using the powerful Saturn V rocket. The crew spent three days travelling to the Moon before the lunar module landed in the Sea of Tranquility on 20 July.After landing, Armstrong famously told Earth, “The Eagle has landed.” He later became the first person to walk on the Moon and said, “That’s one small step for man, one giant leap for mankind.”During their two-and-a-half-hour Moonwalk, the astronauts collected 21.5 kilograms of lunar rocks, placed scientific experiments on the surface, and planted the United States flag.After Aldrin’s quick repair allowed the Eagle to return to orbit, the crew began their journey home. They landed safely in the Pacific Ocean on 24 July 1969. After a 21-day quarantine to protect against possible lunar contamination, the astronauts returned to public life.
Rather than panic, Aldrin searched for a solution.
The cost of reaching the Moon
Before the Apollo missions, NASA invested heavily in astronaut preparation, making the programme one of the most expensive and demanding space projects in history. The Apollo programme cost about $25.8 billion between 1960 and 1973, which is estimated to be more than $250 billion in today’s money after adjusting for inflation. A large share of this budget supported astronaut training, spacecraft development, mission planning, and testing.Astronauts underwent years of intensive preparation before each mission. They received classroom instruction in spacecraft systems, orbital mechanics, navigation, geology, and engineering. Because Apollo astronauts were expected to collect lunar rock samples, they trained with professional geologists and studied volcanic landscapes in places such as Arizona, Hawaii, and Iceland, where the terrain resembled parts of the Moon.Physical fitness was another key requirement. Astronauts followed strict exercise programmes and underwent regular medical examinations. They also trained in simulators that recreated every stage of the mission, including launch, lunar landing, spacewalks, and emergency situations. Water survival exercises prepared them for splashdown in the Pacific Ocean, while aircraft flights in reduced-gravity conditions helped them practise working in near-weightlessness.This extensive preparation ensured that Apollo crews could operate complex spacecraft, respond to unexpected problems, and safely complete humanity’s first missions to the Moon.
