I might as well elaborate on this for the bit.
Stargate SG-1 is a show that comes from a movie. The gist of it is that a giant stone ring was found in Egypt once and the US military got its hands on it on the off chance it could be used to kill more efficiently. Except it goes wrong as it turns out it's a way to travel to other planets and they immediately piss off an alien.
Stargate isn't a movie that would be made today. It's about the military immediately going to war with said alien, who used his technology to be adored as a god by his human slaves. The god in question? Well, it was Ra, obviously.
The ancient Egypt aesthetic still goes strong in the galaxy. The gods are aliens. The pyramids? They're on many planets as they're in fact landing pads for alien spaceships. The spaceships have golden walls and drapes because an evil overlord needs all the comforts.
SG-1 essentially picks up from that with a few changes like MacGyver taking on the role of the coolest soldier of the bunch and the lore expanded to allow for a monster of the week narration. After killing Ra (it's a movie from 1997, the bad guy died and a fork has been found in the kitchen, it hardly a spoiler), a new alien comes to Earth using the Stargate, kills some red shirts, refuses to elaborate and leaves.
A new team is formed to go fuck him up, the SG-1, which indeed entails the presence of other teams that will be sent to other planets off screen. But it turns out Apophis, the new bad alien guy, is Ra's brother and also has just a few thousand more soldiers at his disposal than his brother did in the movie. So the SG-1 does the only reasonable thing: grabs Kratos (yes, it's that guy!) and leaves.
They report back to the base that the ancient Egypt aesthetic still goes strong in space and that the guy they killed indeed has a family. The Goa'uld are, surprisingly, a whole race of parasites that thrive by possessing human bodies and enslaving entire planets and indeed, they're all named after Egyptian gods (plus the occasional exception in later seasons).
They're all evil, therefore they must be fought before they invade Earth again.
Now, since the military is involved, various bases and whatnot will be mentioned and visited of course. Fort Baker appears in one episode, thus bringing another set of space explorers to Starfleet Command. The SG-1's primary mission is to retrieve alien technology that can be used in the battle against the Goa'uld. So more than anything, they talk about the place where this stuff is stored, Area 51.
Imagine the face of everybody's favorite basement dweller John Bishop when some nerds from the air force start sending tons of working alien tech every week, including a spare Stargate. He'd be livid and then he'd be furious when he isn't allowed to get involved with the research because the EPF is mainly researching genetics. Why would he be interested in those awesome alien guns everyone at Stargate Command is now using?
Still, all of that pales in comparison to when Bishop finds out about their new allies.
As it turns out, the Goa'uld weren't the only ones hijacking divine pantheons to establish their domains. Strong of their even more advanced technology, the Asgard have claimed a few planets under their protection, including Earth.
Introducing Thor and his brother Loki.
I'm sure you see where I'm going with this.
Bishop is categorically not allowed to be within 50 kilometers from Thor whenever he visits Earth. With how infamous he probably is and the detailed accounts of what certain grey aliens did to him, some think that is still a generous restriction. Bishop is vocally against being with the Asgard and likely calls their bluff regarding their ability to actually fight the Goa'uld early on. He's right about it, the planet is often left to fend for itself. But the SGC is actually delivering results while the EPF is draining the budget with little to show off, so he's gladly dismissed.
Then one day a de-aged Colonel O'Neill of the SG-1 shows up at the base.
You see, the Asgard are clones. At some point they allegedly stopped reproducing and began transferring their consciences to new cloned bodies. This worked for a few centuries, but then the DNA deteriorated so much they're essentially on the brink of mass extinction. All the scientists they can spare are working on a solution but so far, to no avail.
As the remaining SG-1 tries to figure out how O'Neill shrunk overnight, they investigate similar cases and it turns out many more have been abducted by a little grey man. Panic ensues as their best allies ever might be problematic and they call Thor to figure this mess out.
As they learn, Thor, the supreme commander of the Asgard fleet, has a brother named Loki, a much sneakier scientist who has been secretly experimenting on humans to find compatible DNA to refresh the gene pool. He doesn't know why the clone only grew up to be a kid but at that point he didn't care to find out. Thor takes Loki back home, the clone is sent off to be a normal kid and they live happily ever after until next week, including Bishop who will now bring up this accident at every meeting.