The Fallen Astronaut
While Memorial Day honors veterans who have died in combat, there are also the men and women who have died serving their country in the name of space exploration.
Memorials to their sacrifice can be found across the globe -- and in space.
On Aug. 1, 1971, Apollo 15 astronauts David R. Scott and James B. Irwin, placed this plaque and a small aluminum statuette on the surface of the moon.
The plaque bears fourteen names -- of both astronauts and cosmonauts -- who died in the pursuit of exploring space.
Those honored are listed in alphabetical order: Charles A. Bassett II, Pavel I. Belyayev, Roger B. Chaffee, Georgi Dobrovolsky, Theodore C. Freeman, Yuri A. Gagarin, Edward G. Givens Jr., Virgil I. Grissom, Vladimir Komarov, Viktor Patsayev, Elliot M. See Jr., Vladislav Volkov, Edward H. White II, and Clifton C. Williams Jr.
Space Mirror Memorial
Located at the Kennedy Space Center in Florida, the Space Mirror Memorial honors 24 American astronauts who died in the line of duty on a giant, black granite surface 42-feet high and 50-feet wide.
The mirrored surface reflects the sky, making the names appear to float. Names of the deceased are grouped based on the incident in which they died.
The memorial was dedicated in 1991 and paid for by Florida residents who purchased Space Shuttle Challenger mission automobile license plates, according to the Kennedy Space Center website.
This stray mutt-turned-astronaut was launched into space on Nov. 3, 1957 on Sputnik II.
Sadly, the Russian space program had yet to perfect its techniques. Laika was used as a guinea pig with assuredly fatal results -- the Russians never had a recovery plan in place.
The time Laika spent (alive) in orbit has been a matter of debate for decades, with initial reports claiming the dog survived for several days. Recently a report suggested the dog had survived only several hours.
Laika has since been commemorated by stamps in several different countries and a memorial statue was built in her honor in Moscow.
Monument to Yuri Gagarin
Cosmonaut Yuri Gagarin was the first man in space in 1961 and has long been a hero to Russians and space lovers around the world.
Gagarin was killed in a plane crash in 1968.
This massive statue, erected in 1980, is on display at Yuri Gagarin Square in Moscow.
When the now-deceased Mars rover, Spirit, landed on the red planet in 2004, NASA officials named the site as a reminder of the cost of space exploration: Columbia Hills.
"During this time of great joy for NASA, the Mars Exploration Rover team and the entire NASA family paused to remember our lost colleagues from the Columbia mission," NASA Administrator Sean O'Keefe said in a press release from the dedication.
Columbia Hills was one of Spirit's regions to explore, with Husband Hill named after shuttle Columbia's commander Rick Husband.
Space Shuttle Columbia exploded shortly before it was supposed to land on Feb. 3, 2003. All seven astronauts on board were killed.