Quick, name a space station!

Did you just say “the  International Space Station”? I’m not surprised.

It’s the biggest and longest-running space station that’s ever existed. In fact, if you were born after October 31, 2000, you’ve never known a day where a human wasn’t in space. Thanks to the ISS.

But this video isn’t about the ISS. Because humans have been in the space station game since the 1960s. Sometimes, people never get to live on them.

Sometimes, people have to do a bunch of repairs so that they can start living on them. And sometimes, you get stranded when your coworkers steal your ride home. [♪INTRO] During the Space Race, the Americans and Soviets didn’t just compete to see who’d leave the first bootprints on the Moon. They were also both interested in setting up longer-term space bases in Earth orbit.

They thought space stations would be perfect for studying the effects of living in space, doing some interesting science and of course, spying on each other. The first American space station program was called the Manned Orbiting Laboratory, or MOL, and it came to us courtesy  of both the US Air Force and an agency called the National  Reconnaissance Office. The idea behind MOL was to launch single-use, modified Gemini capsules into orbit, with two-man crews who’d stay up there for about a month and take pictures  of the Soviets, mostly.

And in November 1966, MOL had  its first successful launch: an uncrewed craft dubbed OPS 0855. For a bit of context, this was just a few months before the infamous Apollo 1 fire. It was also about a year  before the original series of Star Trek featured its first space station which spent part of the  episode infested with tribbles.

After about two months in orbit, OPS 0855 reentered Earth’s atmosphere. And three years later, the  whole MOL program was cancelled. Partly due to cost overruns, partly due to the advent of remotely-operated spy satellites.

Now, the capsule lives at the Cape Canaveral Space Force Museum. But technically, OPS 0855 wasn’t the only part of its program to go to space! By 1967, seventeen military pilots had been recruited for the MOL’s own astronaut corps.

Six of them wound up joining NASA and traveling on the space shuttle. Presumably, they did a lot less espionage than they originally trained for. In January 1969, the same year MOL was cancelled, the USSR beat the US in yet  another space race milestone: Two Soyuz spacecraft doc ked together, and cosmonauts moved from one to the other.

If that sounds like a  relatively minor accomplishment, take a moment to think bigger. Literally. If you want a space station that’s bigger than the rockets you use to launch them into space, you’ll want a way to connect  multiple smaller modules together, and get the inhabitants to move between them.

Now, the Soviets didn’t have the best plan for future space stations right then and there. The cosmonauts in this mission had to go outside one Soyuz to get into the other. Which is something folks on the ISS definitely don’t have to worry about.

But after a couple years of  cooking, the USSR delivered the first occupied space station,  courtesy of the Salyut program. Actually, there were two programs. The civilian “Salyut” space stations, and the “Almaz” space stations  that looked very similar and were billed as Salyuts, but were  actually military operations.

So when Salyut-1 launched in April 1971, it was officially a civilian mission and contained telescopes and science experiments. But it’d be a pretty safe bet they were doing what the MOL program had  also been planning in secret, just, you know, on the other guys. Unfortunately for Salyut, things  got off to a very rocky start.

The first space station had  to launch before its crew, and when that crew arrived four  days later, they couldn’t get in. So they turned around and went home! Two months and one frantic  re-design of the docking mechanism later, the next crew  successfully entered the station.

One cosmonaut celebrated his birthday. They watered plants. Everything  seemed to be going great.

Even a small electrical fire halfway through their stay wasn’t enough to call it quits. And as the first humans to occupy a space station, they accomplished a lot of firsts. Unfortunately, that includes  the worst possible first: the first deaths in space,  because all three men perished inside their Soyuz craft on  the journey back to Earth.

Inquests after the fact  chalked it up to a bad pressure relief valve that broke and  vented out all their air. And at the time, wearing  pressurized suits wasn’t mandatory, so they had no backup plan. They were dead within minutes, long before their capsule reentered the atmosphere.

So Salyut-1 had no more visitors. But on top of requiring future crews to wear those suits on all trips to and from space, the USSR rolled out even more Salyut stations. Including two successful military stations, codenamed Salyut-3 and Salyut-5.

Then came Salyut-6, in 1977. This was the first real long-term space station. It stayed up for four years, and 17 different Soyuz missions visited it.

But that pales in comparison to Salyut-7, which racked up nine years of service. It was pretty much the crown jewel of the program. And while plenty of interesting  stuff happened on Salyut-7, here’s one particularly exciting nugget: In 1985, the station found itself unoccupied for a few months, and it lost power.

Not only that, its back-up radio  transmitter went dark, meaning there was no more communicating  with it from the ground. So in what may be the most herculean feat of cosmonaut-ery ever recorded, a two-man team spent four months training, and then went up to fix it. The first problem they had to tackle was the fact that the station had started to spin.

Meaning in order to dock, they needed to match the spin with their own spacecraft manually. The automated systems they would normally use were no good, here. Miraculously, they managed to latch on.

But once they opened the  hatch, they found the internal temperature of the station had plummeted. They described it as “Kolotun,” which roughly translates to “freakin’ cold!” They had good reason to believe it might be cold, because they knew it hadn’t  been powered for months. Also, there was a whole planet blocking the Sun for a good chunk of each orbit, preventing things from staying warm on their own.

So it was a good thing they came prepared! They put on wool hats and  winter coats, and got to work. One of the first things they  did was use the thrusters on their docked Soyuz spacecraft  to move Salyut’s solar panels back into a position  where they could absorb a bunch of sunlight, and  start charging the batteries.

Then carefully and methodically, they went through the  station’s individual modules, and revived it. The cold had damaged some of the equipment, so some of the fixes required  a little bit of ingenuity. Like, when the water in the tanks  froze, the water heater broke.

So to heat up fluids, they resorted to using a floodlight meant for filming TV clips! It took 10 days for these two  men to revive the station. But it was worth it, because Salyut-7 continued to serve as a space base for another six years!

From space tragedy to heroic station rescues… and even, allegedly, the  first gun fired in space... the Salyut program had it all. But before we get to our next space station, we’ve got to keep everything running in our definitely-not-a-space station. So here’s an ad.

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Don’t worry. NASA also had plenty of drama with their first space station. It was called Skylab, and it was built from a repurposed segment of a Saturn V rocket.

Better known as the rocket we used to send people to the Moon. Skylab was launched in May 1973. All three crewed missions were  completed by February 1974.

And those crews did all  sorts of interesting things, like observe hurricanes from above, take pictures of a huge solar flare, test the effects of space on the human body, and due to a little mishap with some fruitflies fail to test how spiders spin  their webs in microgravity. Did they also spy on the Soviets? I can’t say.

But I can say the third Skylab crew didn’t go on a day-long strike. That somewhat popular myth  seems to have started in a New Yorker piece from 1976, despite NASA releasing the mission’s communication transcripts including for the day of the  supposed strike two years prior. Did the astronauts complain  about being overworked?

Yeah. Did they get NASA to  ease off thanks to what one of those astronauts called “the first  sensitivity session in space”? Also yeah.

No strike necessary. So where’s the real drama I mentioned? Back with the first Skylab crew.

Because the mere launch of the  station had damaged a few of the solar arrays, causing them  to jam while trying to unfold. As Salyut-7 would demonstrate years later, those are kinda important  to have working correctly. Even worse, Skylab’s micrometeorite shield deployed too soon and got ripped off the station.

Any future inhabitants were now at risk of getting a hole in the side of their space station. But there was a more immediate problem, since no one was currently onboard: Skylab started to heat up, because the shield was supposed to shade the station  from the intense sunlight. Engineers were worried that the plastic inside would start to melt and release poisonous gasses!

For context, sunlight heats up the outside of the ISS to about 120 degrees Celsius. Don’t worry; it has AC. Skylab-2, the first crewed mission on the scene, arrived 11 days after the station’s launch.

After maneuvering their Apollo  spacecraft into position just a few feet away, one  of the astronauts attempted to fix the jammed solar panel by… poking it with a 10-foot pole  while someone held his legs. It sort of worked, but not  enough to free the panel. Eventually the crew had to dock with Skylab which took eight attempts because the electrical systems weren’t working properly.

They then managed to fix the  shade problem by sticking what amounts to an umbrella  out a tiny scientific airlock, then expanding it to block the heat from the Sun. So we’ve seen Salyut-7 get too cold, and Skylab get too hot. The  next one better be just right.

In 1986, the USSR launched  its newer, bigger version of the Salyut station: Mir. But  they still had Salyut-7 up there. Its last crew had been evacuated  due to a medical emergency, and they hadn’t done everything  they were supposed to.

What’s more, Salyut-7 still had lots of useful, already-in-space equipment that could be re-used if the Soviets could get it to Mir. So after the crew of Soyuz T-15 spent a few weeks on Mir getting used to space, they packed back into their Soyuz capsule, flew over to Salyut-7, gathered up as much instrumentation as they  could fit inside with them, and brought it back to the shiny new station. To anyone who’s had to slowly  move apartments with just a car, this mission might sound like  a minor annoyance at best.

But this is outer space, so it was an absolute feat of orbital mechanics. Docking with something travelling nearly 30,000 kilometers an hour once is hard. Doing it three times between two different space stations is ludicrous.

Fifteen years and more than 100 visitors later… not to mention a serious mold infestation, a fire, and the fall of the  Soviet Union, Mir was deorbited. By that time, the ISS was already hosting its second crew, Expedition 2. So you might think that makes the ISS the only working space station  in Earth orbit right now.

But assuming nothing’s gone horribly wrong since we wrote this episode, that  thought would be wrong. In 2011, China launched the first  of its Tiangong space stations. Tiangong-1 burned up in the  atmosphere seven years later, after it lost the ability to  communicate with the ground.

But of those seven years, it  was only occupied for 24 days, across 2012 and 2013. That’s because it was mostly  a test to confirm China could successfully launch a space station, and have all of the critical systems still working once it got to orbit. You know, unlike Skylab.

Their second station,  Tiangong-2, launched in 2016. It was basically a souped-up  version of its predecessor, but it was also only a test, so it  lasted a mere three years in orbit and was only occupied for one  short stint of about one month. But finally, there’s Tiangong-3, which launched in 2021 and  is still up and running.

In fact, it’s got a bunch of modern conveniences, like a real oven that can cook chicken wings! It’s quite a bit smaller than  the ISS, with a livable volume of up to 110 cubic meters  compared to the ISS’s 388, but there are plans to expand it from its current set of three modules to six. And because space really is  that dangerous, of course Tiangong-3 has had to deal  with its own challenges.

Like in November 2025, three taikonauts were briefly stranded on board. A new crew, Shenzhou 21, had  recently arrived via their Shenzhou spacecraft, and it was now time for Shenzhou 20 to undock their  own craft and head home. Luckily, before they actually undocked, someone noticed cracks in one of the windows.

It had probably been hit by some kind of debris. But whatever the reason, it was no longer fit to carry the Shenzhou 20 crew. Instead, they commandeered Shenzhou-21’s ride, and touched ground a mere week behind schedule.

The Shenzhou 21 crew was stuck on the station without a viable escape vehicle for about 11 days, while they waited for their space agency to send an emergency backup. That backup came in the form  of an uncrewed Shenzhou-22, which was launched packed with  fresh supplies and a patch made specially for the  Shenzhou 20’s busted window. Personally, I would have also made a commemorative patch for the crew to sew onto their uniforms, but I’m not in charge of a space agency.

Even though I should be. Two of the taikonauts took a spacewalk to check out the window more carefully. They wound up applying the patch  to the inside of the window; however, no one was going to put their life on the line to see if the patch would hold.

On January 19, 2026, the patched-up and unoccupied Shenzhou-20 arrived back on  Earth for further analysis. And as of April, when we wrote this episode, the formerly stranded crew of  Shenzhou 21 were still onboard. Hopefully, their return home was smooth sailing… or whatever you call safely  plummeting through the Earth’s atmosphere and colliding with Inner Mongolia.

If you know anything about space, you know that it’s hard to go there,  and even harder to stay there. And while the ISS is certainly awesome and deserves a lot of attention, there has been a heck of a lot of crazy stuff that’s happened on, and also  outside, other space stations. Or not happened, if you’re  the cancelled MOL spybase.

Sorry no one got to poke you with a stick, or bring you chicken wings. [♪OUTRO]