In response to a question from reader Derryck Morton, this article explores whether liquids can exist in the vacuum of space. The piece explains that the existence of liquids requires a specific range of temperature and pressure. In the vacuum of space, where pressure is virtually zero, the boiling and freezing points of substances converge, meaning that liquids cannot form or remain stable.
Instead, matter in space exists either as a solid or a gas, depending on the environmental temperature. This principle applies universally, even to substances like mercury and metals that are liquids under Earth-like conditions.
However, the article notes that this does not mean liquids are entirely absent from the Universe. In environments where pressure exists—such as within planetary atmospheres or beneath a planet’s crust—liquids can indeed form and persist. These conditions create the necessary parameters for matter to remain in a liquid state.
The article serves as a concise scientific explanation tailored for a general audience, debunking the notion of free-floating liquids in outer space while acknowledging the potential for liquid environments elsewhere in the cosmos.
