— A design studio's proposal for a new collectible set seeks to "pin" down the pivotal probes from space exploration history.

Chop Shop on Tuesday (April 8) began seeking fans of robotic satellites and interplanetary spacecraft to help them create a series of hard enamel lapel pins. In addition to seeking pledges through a crowdfunding campaign, the Philadelphia-based store is turning to the public to pick out the probe for the fifth pin the line.

"Each of these missions represents the best of what human intellect can achieve — and for many, they also carry a strong sense of nostalgia," reads Chop Shop's campaign description on the BackerKit website.

The featured missions were selected through a poll conducted by The Planetary Society, with the top results being the Voyager "Grand Tour" program of the 1970s and 1980s; the Cassini/Huygens mission to Saturn and its moon Titan; Mars Science Lab (Curiosity and Perseverance); and Earth's first-ever artificial satellite, the Soviet-era Sputnik.

Chop Shop is basing the pins' designs on a popular collection of posters they produced in 2014 and 2015. The Historic Robotic Spacecraft Series has since inspired the production of decals, toy blocks, patches, t-shirts and glassware.

"As of now, only the Voyager enamel pin has been produced. While the rest of the missions already exist as part of our original poster series, they've not yet been translated into enamel pins — but they're ready to go," the company's reps wrote.

The pins will be made of hard enamel with a silver line structure. Measurements of each pin will vary slightly due to their shape, but they have been designed to appear as a set. Individual pins will cost $8.50 each, while a full set of five mission is $40. A $24 trio of the first three designs — Voyager, Cassini and Mars Science — is also being offered.

"Voyager was a defining part of the '80s, with its grand tour of the outer planets and its tie-in to Carl Sagan's 'Cosmos.' In the '90s, Galileo gave us a dramatic look at Jupiter and its moons. Then in the 2000s, Cassini arrived at Saturn, and two remarkably durable rovers landed on Mars," reads the Chop Shop description.

For the fifth pin, Chop Shop has invited the public to vote on nine different choices, ranging from NASA's Messenger mission to orbit Mercury to the New Horizons probe that flew past Pluto. Other choices include the Soviet-era Venera probes that touched down on Venus; the Viking landers and Mars Exploration Rovers Spirit and Opportunity; the Galileo and Juno missions to Jupiter; the European Space Agency's Rosetta and Philae spacecraft that studied a comet; and the now interstellar Pioneer 10 and 11 probes.

Voting is open through April 14, while BackerKit pledges close on April 28 at 9:00 p.m. EDT (0100 GMT on April 29). The campaign exceeded its $1,000 goal within hours of first being offered on Tuesday (April 8) from the support of more than 25 backers.

Chop Shop expects to begin shipping the Historic Robotic Spacecraft Series pins in early June.