Greens senator Nick McKim has unleashed on One Nation's Malcolm Roberts, bringing a tin foil hat into the Senate chamber for the climate sceptic to wear.
Senator Roberts has made headlines with his conspiracy theories about climate change since he was elected to the Senate in July.
He's called for Australia to leave the United Nations, likened the South Australian government to the Taliban for its push toward renewable energy and accused NASA and Australia's Bureau of Meteorology of manipulating the facts around climate.
On Monday, he brought on an hour-long debate in the Senate over the "disputed theory of global warming".
But what about the moon landing? Senator McKim asked.
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And Tasmania - is it really an island?
"You think NASA is trying to read your thoughts through the fillings in your teeth," Senator McKim said.
"Or maybe the lizard people are stealing your thoughts through the special implants in your brain that they put in while you were sleeping."
He then produced a tin foil hat, before being asked to remove the prop.
"I was trying to help Senator Roberts. I thought he might have dropped his hat," Senator McKim said.
"Haven't we all got better things to do then debate the conspiracy-theory laden rubbish that you bring into this place?"
Senator Roberts said the world of the "green guilt elites" came crashing down with the election of Donald Trump as US president.
"That night they collectively wet their beds," he said.
