Mariner 2 was the first successful spacecraft in the NASA Mariner program and
the first space probe to conduct a successful planetary encounter. It passed
within 22,000 miles of Venus on December 14, 1962.The spacecraft was
designed and built by the Jet Propulsion Laboratory of the California Institute
of Technology.

President Kennedy (far right) is presented with a model of Mariner 2

 
Isaac Lee Hayes, Jr. (August 20, 1942 – August 10, 2008)

The Apollo 15 prime crew astronauts from left: Commander David R. Scott, Command Module Pilot Alfred M. Worden, and Lunar Module Pilot James 
B. Irwin

Apollo 15 was the ninth manned mission and was the first where the
Lunar Roving Vehicle was used. It concluded on August 7. At the time,
NASA called it the most successful manned flight ever achieved.

The Apollo 15 36-volt electric Lunar Roving Vehicle was one of three that went
to the Moon

         
              Donald Herbert Kemske (July 10, 1917 – June 12, 2007)

Herbert was the creator and host of NBC’s Watch Mr. Wizard (1951–65, 1971–72)
and of Mr. Wizard’s World (1983–90), which were educational television programs
for children devoted to general science and technology experiments.

Sally Kristen Ride is a physicist who joined NASA in 1978 and became the 
first American woman, then the youngest at 32, to enter space. She left 
NASA in 1987 to work at Stanford University’s Center for International
Security and Arms Control. In 1989, she became a professor of physics
at the University of  California, San Diego and Director of the California
Space Institute.   

Sally Ride turned 61 on May 26.