Astongate is a term used to describe a political scandal that happened in Australia in 1996. It was caused by the Prime Minister at that time, Paul Keating, and his rival, John Howard.
Keating and Howard were competing for the Prime Minister position, and Keating was about to lose the election. So he made a last minute decision to promise $10 million of the government's money to a company called Astonaire. Astonaire was owned by a wealthy businessperson who supported Keating. This last minute decision was seen as a way for Keating to try to win the election by buying support from the wealthy businessperson.
Unfortunately for Keating, his plan backfired and he lost the election. Because of his actions, the Australian government started to investigate and found out that Keating had misused public funds.
Keating was then charged with misusing the government's money and he had to apologize. This scandal was called Astongate and it has become a famous example of a political scandal.