How do We Know the Distance to the Moon? To the Planets?

Today in History, January 10, 1946:

ÔÇťOperation Diana”.

The US Army Signal Corps, using a “bedspring antenna” radar from a World War II era US Navy ship, somewhat modified, bounces a signal off of the moon, which took 2.5 seconds to return to the Earth.

The experiment was the precursor to using Radar to determine the distance to other bodies, such as Saturn, and for learning to communicate with later spacecraft outside of Earth’s atmosphere.

Diana was the Roman Moon Goddess, and this project would take the lead in naming later space projects after Roman Gods.

The Battle of Alcatraz

Today in History, May 4, 1946:

Call in the Marines! The Battle of Alcatraz.

On May 2nd, three inmates on D Block of Alcatraz prison managed to overtake the block of cells. One of them managed to expand and crawl between bars leading to the catwalk above the cells and overpower the guard there.

Soon they had imprisoned the guards in two cells and taken their weapons. Now they only needed to find the key to the “yard” and they could steal the island’s launch to escape. However by the time they found the key, they had tampered with the lock so much that a security feature kicked in and they were sealed inside.

Over the next couple of days they fired on guards outside and on the guards they had imprisoned inside, killing 3 and injuring 14.

The Warden called for help from Marines stationed at the nearby Treasure Island Naval Base, many of whom were fresh from fighting Japanese hidden in caves in the Pacific. The Marines assaulted D Block with machine gun fire, grenades and mortars. When the guards went to secure the building, they found the three ringleaders dead in a utility corridor to which they had retreated. Two more inmates would later be executed for their role in the attempted escape.

Send in the Marines!

Today in History, May 4, 1946:

Call in the Marines! The Battle of Alcatraz. On May 2nd, three inmates on D Block of Alcatraz prison managed to overtake the block of cells. One of them managed to expand and crawl between bars leading to the catwalk above the cells and overpower the guard there. Soon they had imprisoned the guards in two cells and taken their weapons. Now they only needed to find the key to the “yard” and they could steal the island’s launch to escape. However by the time they found the key, they had tampered with the lock so much that a security feature kicked in and they were sealed inside. Over the next couple of days they fired on guards outside and on the guards they had imprisoned inside, killing 3 and injuring 14. The Warden called for help from Marines stationed at the nearby Treasure Island Naval Base, many of whom were fresh from fighting Japanese hidden in caves in the Pacific. The Marines assaulted D Block with machine gun fire, grenades and mortars. When the guards went to secure the building, they found the three ringleaders dead in a utility corridor to which they had retreated. Two more inmates would later be executed for their role in the attempted escape.