NASA animation of the deployment of the ARISSat-1 educational satellite from the International Space Station by cosmonauts Sergei Volkov and Alexander Samokutyaev. Image Credit/NASA TV

Persistent spacewalking cosmonauts Sergei Volkov and Alexander Samokutyaev successfully deployed ARISSat-1, a 57-pound educational satellite from the International Space Station on Wednesday to commemorate the 50th anniversary of Russian Yuri Gagarin’s first human spaceflight.

Gagarin made a single orbit of the Earth on April 12, 1961.

Troubles with ARISSat-1, a prototype for a series of educational satellites, forced the spacewalkers to defer the six hour excursion’s top priority, the transfer of a cargo boom from the station’s aging Russian Pirs airlock to the newer Piosk module, a multi use airlock compartment.

The transfer of the STRELA-1 boom will be reassigned to a future spacewalk, according to NASA spokesman Josh Byerly, who was part of the Mission Control team in Houston that monitored the Russian-led outing.

ARISSat-1, also known as Radioskaf-V, is a collaboration between the Radio Amateur Satellite Corp, RSC-Energia, NASA’s office of education, the ISS National Lab project and the Amateur Radio on ISS working group.

The prototype is equipped with a single student experiment, a Russian atmospheric pressure sensor.  The spacecraft will transmit images of the Earth as well as greetings saluting Gagarin’s flight recorded by students from around the world in their native languages.

Future versions of ARISSat-1 will carry four student experiments.

Cosmonauts Sergei Volkov and Alexander Samokutyaev install a science antenna on the Russian segment of the International Space Station. Photo Credit/NASA TV

As they began their spacewalk with plans to toss the satellite from the station, Russian flight control teams noticed the absence of a second antenna in live video views.  After a  round of troubleshooting, Moscow directed the spacewalkers to continue with the deployment, though the second antenna was either tucked inside the satellite or missing altogether.

As part of their hastened inquiry into the status of ARISSat-1 on Wednesday, Moscow contollers consulted with Dmitry Kondratyev, who was the station’s commander when the disassembled satellite reached the station in February aboard a Progress cargo capsule.

ARISSat-1 is expected to transmit for about three months, and re-enter the Earth’s atmosphere in about nine months.

Volkov and Samokutaev also equipped the station’s exterior with a laser antenna. The device will accelerate the transmission of data from Russian science experiments to ground stations.

The delayed STRELA-1 transfer will lay groundwork for the departure of Pirs. Russian plans to replace the 16-foot-long compartment with the larger Multipurpose Laboratory Module in 2012

The new module will come equipped with a European robot arm.