Wikipedia:Selected anniversaries/January 28

January 28:

• 1077 – Walk to Canossa: Pope Gregory VII lifted the excommunication of Henry IV after the Holy Roman Emperor made his trek from Speyer to Canossa Castle to beg the pope for forgiveness for his actions in the Investiture Controversy.

• 1573 – The Warsaw Confederation was signed, sanctioning religious freedom in the Polish-Lithuanian Commonwealth.

• 1820 – A Russian expedition led by naval officers Fabian Gottlieb von Bellingshausen and Mikhail Petrovich Lazarev approached the coast of Antarctica.

• 1855 – A train on the Panama Railway made the world's first transcontinental crossing, a 48-mile (77-km) trip from the Atlantic Ocean to the Pacific Ocean across the Isthmus of Panama.

• 1986 – The NASA Space Shuttle Challenger disintegrated (pictured) 73 seconds into its tenth mission, killing all seven crew members.

More anniversaries:

• January 27
• January 28
• January 29