Cosmos had no funding or budget - all equipment was either owned prior to filming or borrowed, all locations were lent and all cast and crew worked on the project without a fee.
With the exception of scoring the film, directing brothers Elliot & Zander Weaver, took on all major production roles including: screenwriting, prop making, lighting and camerawork, sound recording, editing, sound designing and sound mixing, VFX, poster art and trailers creation.
Cosmos took 5 years to produce from start to finish.
Excluding the directors, the crew of Cosmos at its busiest point during filming, totaled just three. 85% of the film was shot with the two directors and a crew of just one.
The folk song, sung by the team during the film is called "Uncle Rat" - performed by Charles Fulton, recorded by S.R. Cowel and is available to listen to for free on the library of congress website.