How many people are in space at any point in time?
Why the only humans in space are the ones on the ISS, and a short timeline of human spaceflight ‘first times’
Usually 3 or 6. When the International Space Station (ISS) is fully manned, there are 6 people on it. The crew rotates out periodically — 3 return back to Earth, leaving 3 on the station until the next 3 people arrive up at the station.This way, there are always at least 3 people at the station.
When American or Russian shuttles do go up, they carry between two to seven people, so at some points there may even be up to 10 people at once. But again, that’s temporary, and the number drops to 3 or 6 eventually.
The ISS is the only place in space with humans.
Whenever humans are in space, they’re either going to the ISS, on the ISS, or returning from the ISS. There are almost no other crewed missions that are taking part anywhere else in space (China’s space lab Tiangong-2 was deorbited in 2019). You may ask — what about moon landings? Mars even?
Nope. Neil Armstrong and Buzz Aldrin landed on the moon for the first time in 1969 as part of the Apollo 11 mission, and 10 more have been to the moon since. Actually, the last two people to step on the moon were Gene Cernan and Jack Schmitt from the Apollo 17 mission in 1972. That means the only time that humans have ever been to the moon was in that 3ish year period (1969–1972) almost 50 YEARS ago.
And Mars is still some time away. In 2015, NASA released a plan outlining the next steps in the journey to Mars and aimed for crewed missions to Mars in the 2030s. Elon Musk, via SpaceX, has hinted at a manned Mars mission by 2024. However, such timelines are usually unreliable, so we’ll just have to wait and watch.
What is the ISS?
The International Space Station, a collaborative effort by 5 space agencies — CSA (Canada), ESA (Europe), JAXA (Japan), NASA (United States), and Roscosmos (Russia) — is a modular space station in low Earth orbit.
A space station is simply a spacecraft capable of supporting a human crew in orbit for an extended period of time. Think of an Airbnb floating around in space, except that you need to train for years before the Airbnb host accepts you, and that once you get there you work round the clock doing science experiments, cleaning the home, checking if all the equipment works, and repairing anything if necessary. You have to keep the Airbnb’s doors locked, but occasionally they let you take a walk outside (and since you gotta look dashing, you wear a suit).
Modular, because well…it’s comprised of smaller parts called modules.
The ISS is the biggest human-made thing in space — it’s the length of a full-size American football field. It’s visible by the naked eye as well, since it’s supposed to be the 2nd brightest object in the night sky (after the moon obviously). Also, when we look at videos of spacecrafts docking, it usually looks super slow:
But the ISS is actually zoomin’. It’s going at 8 KILOMETERS per second. That means that the ISS orbits Earth every 90 minutes — and it gets to experience 16 sunrises and sunsets every day.
Anyway, space is cool. Humans are cool.
Fun facts about first times:
First times (general):
1961 — First human in space
1963 — First woman in space
1967 — First landing fatality
1969 — First humans on Moon
1971 — First crewed space station
1971 — First in-space fatalities
1986 — First launching fatalities
2001 — First space tourist
First time (length of stay):
1961 — Person in space for over 24 hours
1965 — People spend 1 week in space
1970 — People spend 2 weeks in space
1973 — People in orbit for 4 weeks
1973 — People in orbit for 8 weeks
1974 — People in orbit for 12 weeks
1978 — People in orbit for 19 weeks (4 months)
1980 — People in orbit for 26 weeks (6 months)
1984 — People in orbit for 33 weeks (7 months)
1988 — People in orbit for 52 weeks (1 year)
1995 — Person in orbit for 427 days (61 weeks, current record)
First time (number of people):
1961 — 1 person in space
1962 — 2 people in space at the same time
1964 — 3 people in space at the same time
1965 — 4 people in space at the same time
1969 — 5 people in space at the same time
1969 — 7 people in space at the same time
1984 — 8 people in space at the same time
1984 — 11 people in space at the same time
1990 — 12 people in space at the same time
1995 — 13 people in space at the same time (current record)
In other news, check out this really cool website that tells you how many people are in space right now, who’s there, and their length of stay so far!
Other crisp resources to check out:
- Astronauts answer student questions, by NASA
- Interesting ISS Q&A board, by a NASA engineer
- ISS facts and figures, by NASA
- List of ISS Expeditions, on Wikipedia
- Plan outlining next steps on journey to Mars, by NASA
- Comprehensive list of spaceflight records, on Wikipedia
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