Forty-five years ago, a simple pen played a critical, if unplanned role in the return to Earth of the first astronauts to land on the moon. Now there are new pens — space pens, no less — to mark the 45th anniversary of the Apollo 11 mission.

Fisher Space Pen, the company that privately-developed and provided the pressurized ballpoint pens used by Neil Armstrong and Buzz Aldrin on the moon, has released two collectible pen sets to commemorate the historic July 20, 1969 lunar landing.

Fisher's "Special Edition" and "Limited Edition" 45th Moon Landing Anniversary pens are modeled after the AG-7, the same writing instrument that the Apollo 11 astronauts had onboard the lunar module Eagle when they touched down at Tranquility Base. The pens have engraved designs and come with accessories to distinguish them as anniversary editions of the original model.

Fisher's Special Edition 45th Anniversary Astronaut Space Pen, which retails for $88, features a blue titanium nitride finish over the original pen's chrome body. The barrel has been laser engraved with "Apollo 11" and streaming stars. [NASA's Historic Apollo 11 Moon Landing in Pictures]

The $600 Astronaut Space Pen 45th Year Moon Landing Celebration Commemorative Pen and Box is limited to just 250 individually-numbered sets. The pen features a black titanium nitride finish over chrome, diamond engraved with a moon landing scene. The boxed pen set includes a blue crystal base with a clear crystal globe engraved with a 3D lunar module.

While the pens highlight Fisher Space Pens' role on Apollo 11, they can also serve as a reminder that another type of pen helped make the moon landing a success.

For decades, Fisher's standard-issue pens have included in a pamphlet or on part of their packaging the story about how a pen "saved" the mission. Sometime after landing on the moon, Armstrong and Aldrin, in their bulky spacesuits, accidentally broke off the plastic switch needed to re-arm the engine that would lift them off the lunar surface.

Aldrin discovered the broken switch lying among the moon dust on Eagle's floor after he and Armstrong returned from making their historic moonwalk.

Fisher, citing a NASA public affairs spokesman, suggests that Mission Control advised the astronauts to retract the point of one of their Fisher-provided ballpoint pens and use the hollow end to push the broken circuit breaker switch. Aldrin, however, recalls it a bit differently.

"Since it was electrical, I decided not to put my finger in, or use anything that had metal on the end," the Apollo 11 lunar module pilot wrote in "Magnificent Desolation: The Long Road Home from the Moon," his 2009 memoir. "I had a felt-tipped pen in the shoulder pocket of my [flight] suit that might do the job."

"I inserted the pen into the small opening where the circuit breaker switch should have been, and pushed it in; sure enough, the circuit breaker held. We were going to get off the moon, after all," Aldrin recounted. "To this day, I still have the broken circuit breaker switch and the felt-tipped pen I used to ignite our engines."

Buzz Aldrin is seen inside the Apollo 11 lunar module Eagle after he and Neil Armstrong finished their historic moonwalk on July 21, 1969. (Image credit: NASA)

Fisher's pen may not have saved the mission (the felt tip pens were provided by the Duro Pen Company) but they are the best well-known writing instruments to be used in space. Over the course of the Apollo missions, nearly 30 Fisher space pens flew to the moon, with 12 reaching the lunar surface.

The 45th anniversary edition Fisher Space Pens are the latest in a line of special pens the company has issued to celebrate its connection to Apollo history. Five years ago, for Apollo 11's 40th anniversary, Fisher released a limited edition pen that was embedded with a small piece of foil flown to the moon.

Click through to collectSPACE.com for more photos of Fisher Space Pen’s new Apollo 11 45th anniversary space pens.

For more information, see Fisher Space Pen’s website at spacepen.com.

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