Hollywood may have eventually won the filmic space race with such early realistic sci-fi depictions of space travel as "Destination Moon" (1950), "Countdown," "2001: A Space Odyssey" (1968) and "Marooned" (1969)--since followed up by the likes of "Gravity" (2013), "Interstellar" (2014) and "The Martian" (2015), but the Soviets seem to have had an early lead in both this fictional space race and the real one if "Cosmic Voyage" is any indication. Although the Germans even before them led in science--and in the partially-realistic Moon movie with "Woman in the Moon" (1929)--the brain drain and wreckage from the Nazis eventually ceased that. Konstantin Tsiolkovsky, father of modern rocketry and, thus, spaceflight, is credited as a consultant on this film, and it shows.
Consequently, the spaceship is launched by rockets--albeit guided by rails that make the endeavor look like a cross between a roller coaster ride and shooting the thing out of a cannon à la Georges Méliès's "A Trip to the Moon" (1902). The cosmonauts floating in space and on the Moon is handled well considering the only prior film I know of to depict weightlessness is "Woman in the Moon." The desolate depiction of the lunar surface appears relatively faithful thanks to an effective combination of confined full-scale sets with actors and stop-motion animation amid miniatures. The space suits that look like old-fashioned diving gear at least addresses the oxygen problem, and the use of radio solves the riddle of communication. There are also a couple of interesting ideas that never materialized in the real-world Moon voyages. The space explorers enter bath chambers to protect them from the bumpy takeoffs and landings, and they spell out "USSR" on the lunar surface to send a message seen through a telescope back to Earth (a rather clever text-based solution methinks for a silent film).
The futuristic Art Deco designs and the moving-camera shots of miniatures look nice, too, although the editing is sometimes choppy. More importantly, all of the space-travel sci-fi is curious stuff, but, unfortunately, the trivial narrative surrounding the trip to the Moon weights the cosmonaut adventure down. The first part of the film is wasted on a pointless rivalry over whether to travel to the Moon and who's to go, and this results in the spaceship basically being pirated by an elderly man (who's probably loosely based on Tsiolkovsky), his seemingly unprepared assistant and a stowaway kid. In fact, there are rather oddly quite a few children in the picture, which seems to be a result of the film's production being promoted by the communist youths of the Komsomol.
Thus, in "Cosmic Voyage," we have a silent, black-and-white moonshot compromised by interpersonal conflict and corruption and ultimately forced upon by a collective of kiddies, old kooks and other comrades. In the Technicolor "Destination Moon," the Americans' first response to this space race was that private industrialists would step in for a weak state. Compare these two films to the turn-of-the-century colonialist reflection of fighting primitive aliens on the Moon in the film by Méliès, and it becomes clear that these pictures of lunacy have as much, if not more, to say about the political climate in which they were made than with anything to do with realistic depictions of science and outer space. Even today, "First Man" (2018), based on the real moon landing, fell victim to a debate among critics and politicians between globalization and nationalism--mostly centered around the depiction or lack thereof of the American flag. Perhaps, they should've taken a page from their Cold War adversary and reflected the initials "USA" back to the lunatics.