Stephen Colbert has spent so much time talking about Donald Trump and Hillary Clinton over these past weeks and months that it must have been a relief to spend a few minutes Thursday night making fun of Gary Johnson.

The Libertarian presidential candidate had his second “Aleppo moment” this week when MSNBC’s Chris Matthews asked him to name his favorite foreign leader… and he was unable to name a single one.

“Libertarians have long been waiting for a smart, respectable candidate to represent their values,” Colbert said. “And the wait continues, because Gary Johnson says some crazy-ass stuff.”

Among the clips Colbert presented to disqualify Johnson was his unwillingness to act on climate change because the sun will engulf Earth in a billion years (he suggests that we humans might need to inhabit other planets). “I believe Gary Johnson already does,” Colbert joked.

Colbert went on to say that Johnson’s “What is Aleppo?” gaffe might explain his overwhelming support from military personnel. “No surprise,” the host said, “because if the president doesn’t know about Syria, there’s no way he’s sending you there.”

“Obviously, Gary Johnson’s ignorance, crazy ideas, and strange tongue exercises make him the most laughable candidate out there. Or, should,” Colbert said, pausing for a quick laugh at Trump’s expense. And now Johnson has brought on former child star Melissa Joan Hart as his Connecticut campaign chair. “That’s right, Clarissa. It’s perfect, because he could really use someone who explains it all to him.”

Despite his 0.1 percent chance of winning the election this fall, according to FiveThirtyEight’s model, and the possibility that he could sway the presidency to Trump, Johnson has rejected calls that he drop out of the race.

“So voting for Johnson might be throwing your vote away,” Colbert concluded. “But c’mon, in billions of years, the sun is going to swallow the Earth anyway.”