Billionaire and SpaceX owner Elon Musk was front and center during Donald Trump's inauguration after donating around $200m to get him elected as outgoing President Joe Biden warns of an oligarchy forming.

President Donald Trump made a bold promise to America minutes after taking the Oath of Office: pledging that an American flag would be planted on Mars.

Elon Musk cheered after newly sworn-in President Donald Trump mentioned Mars in his inauguration speech on Monday. “We will pursue our manifest destiny into the stars,” Trump said, “by launching American astronauts to plant the stars and stripes on the planet Mars.