Question: how long do each air tanks last in space

Andrew Winnard answered on 13 Dec 2015:

Hi 586!

The International Space Station has some large tanks of Oxygen which I think can last up to 100days (Simon might be able to confirm this!). However, this is not the main way the astronauts get their Oxygen. They actually generate it from other sources rather than using the stored Oxygen all the time. For example, you can make Oxygen from water using a process called “electrolysis,” which uses electricity from the ISS solar panels to split water into hydrogen gas and oxygen gas. Each molecule of water contains two hydrogen atoms and one oxygen atom. Running a current through water causes these atoms to separate and recombine as gaseous hydrogen (H2) and oxygen (O2).

The oxygen that people breathe on Earth also comes from the splitting of water, but it’s not a mechanical process. Plants, algae, cyanobacteria and phytoplankton all split water molecules as part of photosynthesis — the process that converts sunlight, carbon dioxide and water into sugars for food. The hydrogen is used for making sugars, and the oxygen is released into the atmosphere

Here is a video for you that explains how to get Oxygen and Hydrogen from water:

PS: The astro support team will start getting evicted this week from Tuesday! If you like my replies where I try to include videos for you then please vote for me – and check out this video I made which explains Tim’s launch so you can follow along easily on Tuesday during the real thing!