Liberal MP Marc Garneau, who was Canada's first astronaut and led the Canadian Space Agency, is "ticked off" that he wasn't invited to Thursday's opening of a Canadarm exhibit and he blames Conservative partisanship for being left off the guest list.

"I'm not very happy," Garneau told reporters on Parliament Hill. "I wasn't looking for a role, I just wanted to be there in the audience."

The Canadarm, a robotic arm that was first used in 1981, was created in Canada and is considered a national icon. A newer version of the Canadarm used on the International Space Station is featured on the new $5 bill that was unveiled Tuesday. Astronaut Chris Hadfield showed off the new bill via satellite from the International Space Station where he is the commander.

Garneau operated the Canadarm on two of his three flights in space and said he always talks about those experiences with immense pride. The robotic arm, used for a variety of functions including satellite repairs, was used on 90 missions in space before NASA retired it in 2011.

Heritage Minister James Moore and Industry Minister Christian Paradis unveiled the new exhibit at the Canada Aviation and Space Museum Thursday morning and Garneau took to Twitter to express his disappointment that he wasn't there: "NASA-donated Canadarm officially unveiled in Ottawa today. Would really have appreciated invitation from Gov't to attend. No such luck."

Garneau said he is partly responsible for the Canadarm being on display at the Ottawa museum, which is why he is even more offended. The iconic piece of equipment was originally going to be kept at the Canadian Space Agency's headquarters near Montreal but when Garneau got wind of that plan he wrote and urged Paradis to consider the public museum in the nation's capital instead.

Urged Paradis to keep Canadarm in Ottawa

He was happy when the government changed its mind and said he thanked Paradis for the decision to move it to Ottawa where it would be seen by more Canadians.

"It's a source of great pride," Garneau said about the Canadarm. "I don't care if I was in the back row, I would have liked to have been there, so I'm very very disappointed."

Garneau said being left off the guest list shows how partisan Prime Minister Stephen Harper's government is and that these kinds of events shouldn't be treated as political. Liberal MP Mauril Belanger, who represents the riding where the museum is located, wasn't invited either but attended the event once he heard about it through other channels.

Belanger told reporters he felt Garneau should have been there.

"I mean, come on. How many MP's have actually used the Canadarm in space?" he said.

The NDP also showed their support for the Liberal MP. Science and technology critic Kennedy Stewart wrote on Twitter that everyone was proud when Garneau became the first Canadian in space and he questioned why he wasn't invited to the event.

"I'm ticked off that this is the kind of atmosphere that we've created here in Ottawa. I think it's disgusting," added Garneau. He said the government was saying the CSA was in charge of the guest list, but the agency told CBC News it did not do the guest list.

Liberal MPs began chanting "Marc, Marc, Marc" when Moore answered a planted question in the House of Commons from a Conservative backbencher about the Canadarm display during question period.

"They can obsess about their caucus mates, we'll obsess about Canadian history," Moore retorted. "Today we had the unveiling of the Canadarm at the museum and we look forward to thousands of Canadians coming through that museum, seeing the Canadarm and seeing its amazing contribution to Canada's space history."

Reporters tried to ask Paradis, the minister responsible for Canada's space program, for comment after question period but he did not stop to answer questions.