On Friday, this happened:

NASA/Wallops/Mid-Atlantic Regional Spaceport with Chris Heller

The event -- a frog, taking an unexpected flight via a rocket -- may seem unusual. But #rocketfrog, as the little guy has become known, is not the first amphibian to, with the help of some human ingenuity, get a little closer to the final frontier. Nor is it the second. Nor is it the third. NASA and other space agencies, in their zeal to test the effects of microgravity on different organisms, have sent many, many other frogs into space -- not accidentally, as was the case with Friday's LADEE launch, but purposely. For science. 

Below, a brief history of frogs in space. Frogonauts, if you will.

1. V2 Rockets, United States, 1950s

According to D.E. Beischer's Animals and Man in Space: A Chronology and Annotated Bibliography Through the Year 1960, frogs were among the many creatures the U.S. included as passengers when it experimented with launching high-altitude balloons, via German V2 rockets, to heights up to 144,000 feet. (Among the other creatures: monkeys, fruit flies, mice, hamsters, cats, dogs, goldfish, and, of course, guinea pigs.)

2. Jupiter AM-23, U.S. Air Force, September 1959 

This is a sad(der) one. The Air Force, in 1959, included two frogs (along with 12 mice) on a would-be flight of one the nation's earliest medium-range ballistic missiles. The rocket, however, was destroyed during launch.

3. Vostok 3A, USSR, March 1961

During the Vostok 3A flights of March 1961, the Soviet Union launched frogs, for the first time, into low-Earth orbit. (Also included: mice and guinea pigs.)

4. Biosatellites I and II, NASA, 1966 and 1967

Frog eggs were among the cargo of NASA's biosatellites -- along with plants, fungi, amoebas, bacteria, flies, wasps, and beetles.

5. Bion flights, USSR, 1960s and 1970s

The Soviet Union's final flights of its Bion satellites included both frogs and fruit flies.

6. The Orbiting Frog Otolith, NASA, November 1970

On November 9, 1970, NASA launched two bullfrogs on a vehicle called the Orbiting Frog Otolith satellite to understand more about how frogs experience space motion sickness -- and, in particular, to study the adaptability of the otolith to sustained weightlessness. ("Otolith" referred to a frog's inner-ear balance mechanism.) The project, part of NASA's Human Factor Systems program, was  -- unfortunately for the frogs -- a one-way mission.

7. Mir Space Station, USSR, December 1990

In December 1990, the Japanese TV reporter Toyohiro Akiyama took a controversial trip to Russia's Mir space station. He brought with him, in the name of science, some Japanese tree frogs.

8. Shuttle Program, NASA, 1990s

While the shuttle program was operational, the U.S. continued the tradition of carrying frogs into space. Shuttle astronauts also counted as fellow passengers, apparently, brine shrimp, newts, fruit flies, crickets, mice, rats, snails, carp, medaka, oyster toadfish, sea urchins, swordtail fish, gypsy moth eggs, stick insect eggs, quail eggs, and jellyfish.

9. And let's not, er, froget that this happened