Vika oxygen generator
Vika or TGK is an oxygen generating system for spaceflight.[1] It is a SFOG, or solid-fuel oxygen generator, a kind of chemical oxygen generator.[1] It is has been used on the retired Mir space station and the International Space Station.[1] It was originally developed by Roscosmos to supplement the Elektron oxygen system on Mir.[1] A Vika module, also known as a "candle", contains about one liter of lithium perchlorate and can provide oxygen for one person for 24 hours.[1]
It was used on Mir when more than three people were on board.[2] Vika needs a supply of canisters to work, which must be flown into space.[2] An example of this is Progress M-34, which carried 60 canisters to Mir in 1997 along with other cargo.[2] If Vika and Elektron stopped working the station would have to rely on a limited supply of bottled oxygen.[2]
After being adopted for use on the ISS, it had the NASA name SFOG, but they also sometimes use the Russian acronym TGK.[1]