Pluto Discovered
On February 18, 1930, Clyde Tombaugh discovered Pluto after nearly a year of searching. It would be another 85 years before the US sent its first space probe there – inspired by a postage stamp!
Exploration
Arizona Becomes 48th State
On February 14, 1912, Arizona was admitted as the 48th state. It would be another 48 years before another state was added to the Union.
National Geodetic Survey
On February 10, 1807, President Thomas Jefferson signed legislation to establish the United States Survey of the Coast. This later became the US Coast and Geodetic Survey and eventually the National Geodetic Survey.
James Cook – First European to Visit Hawaii
On January 18, 1778, Captain James Cook became the first European to reach the Hawaiian islands. The Hawaiians believed Cook had divine powers and considered him a great chief.
New Mexico Admitted as 47th State
On January 6, 1912, New Mexico became the 47th state admitted to the Union.
Death of Sacagawea
December 20, 1812, is generally believed to be the day that Sacagawea died in Kenel, South Dakota. She’s best known as one of the guides on Lewis and Clark’s Corps of Discovery.
First Building in Chicago
On December 4, 1674, Father Marquette erected the first building in what would later become Chicago. He spent the winter there while on an exploratory journey through the region.
Richard Byrd’s First South Pole Expedition
On November 29, 1929, Richard E. Byrd made his first flight over the South Pole. It was the first of five expeditions he made there during his life.
Viking 1 Lands on Mars
On July 20, 1976, Viking 1 became the first man-made object to land on Mars. It was one of the first spacecraft to conduct prolonged scientific studies on the surface on another planet.