Stargate SG-1 and Atlantis - got just the right amounts of science and fiction, drama and comedy, campiness and self-awareness, and is the reason I got interested in physics and programming. Undomesticated equines could not remove me from another rewatch.
Fringe, hands down. An amazing show from start to finish. I also have a soft spot for Warehouse 13, which leans more into the fantastical.
More recently, the first season of Star Trek: Strange New Worlds has been great, and I'm also looking forward to seeing the second season of Severance.
I do not really have a favorite. Star Trek DS9 was good. I do like Strange New Worlds, actually. And Silo is surprisingly good aswell. I don't know if that counts necessarily as scifi. But if you're able to check out Severance, you definitely should.
I think this is a hard question, if you put a gun to my head I would likely choose the 2000's version of Battlestar Galactica even though I don't necessarily feel great about the final episodes. Unless other mini-series that didn't become tv shows aired on the Sci-Fi channel count, then I'd probably pick Frank Herbert's Dune.
Since some mainline good stuff is already mentioned, I'll mention something not already said.
I enjoyed Travelers a lot. The budget constraints show at times, but it gets some very different and compelling overtones and images. The Director speaking from outside of time, one sentence at a time through different people about to die of natural causes... evocative stuff right there.
It used to be Trek in in general, DS9 specifically. But The Expanse has definitely taken over that spot in my heart. It's probably not fair though as I'm sure there's not a lot of differentiation in my memory of the novels from the show.
This is a bit too hard. So many shows I loved: Firefly, Fringe, BSG, Expanse, Killjoys, Dark Matter, Night Sky, Silo (only watched 3 episodes so far but read the books, and it’s everything I wanted), Stargate SG1, Stargate Universe, Person of Interest, Helix (S1, not idea WTF S2 even was about :D)
That’s already skipping stuff I liked, but didn’t love :D
Everything I was going to say has already been mentioned, some numerous times: The Expanse, Battlestar Galactica, Babylon 5, Firefly, Farscape, Fringe, Altered Carbon season 1, Dark Matter, Killjoys, Twelve Monkeys.
So may I offer up Timeless and Warehouse 13? Both character-focussed and on the lighter side, but also dealing occasionally with some pretty deep character arcs. And they were just FUN (especially Warehouse 13).
Also, more recently I really enjoyed The Peripheral (though I would have preferred a proper ending, rather than the dangling threads we were left with - especially since, at the time, we didn't know if there would be a second season).
ETA: Oh, and I haven't seen any Star Wars shows mentioned besides Andor - which was admittedly fantastic. But my favourite Star Wars TV series are SW: Rebels and SW:The Clone Wars. The latter because it added so much depth to Anakin and Obi-Wan, along with many other characters, and also gave us great new characters like Ahsoka and Wrex. And Rebels holds a place in my heart - many of my favourite Star Wars characters come from that series (Hera, Kanan, Sabine... and Chopper!)
Can't recall seeing anything better than The Expanse in the last decade. Love, Death & Robots is great, but that's not a typical TV Show. Altered Carbon S01 was ok.
everyone tells me the expanse is great, including in this thread! i don’t have a great way to watch it though. correct me if i’m misremembering, it’s on prime, right?
Does Lost count here? That's my favorite, otherwise Farscape or Star Trek in general. I started watching the Expanse, it's really amazing, and I see why people like it, but I like the quirkiness of some of the other shows. Farscape is an extremely fun show to watch.
My overall "favorite" is the Expanse as a lot of you apparently agree, but TNG and DS9 have a place of their own.
I want to say that I really enjoyed the remake of Lost in Space, despite the serious "aimed at kids" vibe it has. I think it was a solid production with a lot of nice ideas, in execution if not in originality.
The expanse was fantastic. I also really enjoyed raised by wolves, I was bummed out when it was cancelled after 2 seasons, it was one of the more inventive sci fi shows.
Fringe and The Expanse would probably be my all time favorites. Next on the list: 12 Monkeys, Travelers, and naturally three shows that never reached their conclusion - Westworld, Raised by Wolves and for sure I think 1899 would have been a favorite.
I haven't seen the show but I've recently started reading The Expanse. I'm about halfway through the first book, Leviathan Wakes, and stuff is really starting to pick up. I've somehow not spoiled myself on it at all despite it being a hugely popular series and TV show so I'm really looking forward to the next like, 7 books.
Firefly! I adore the Wild West theme mixed with the sci-fi elements. Feels really unique, and it represents what the spacefaring future probably would look like to the average person. Like everyone else, I'm livid it only got one series, even after all these years.
The Prisoner. No doubt about it. I taped that whole series on audio cassettes with a Radio Shack portable recorder in the 1970s. It's the ultimate cult show.
Sadly, it is mostly unknown to modern audiences. I cosplayed as The Prisoner for several years at a regional SF convention, and only one person recognized me - but from the Simpsons parody rather than the original show!
Babylon 5 is my top pick. If you can get past the aging, low-budget visuals and corny dialogue, you will find a wonderfully crafted show. It can be hard to get into initially, but there is a huge payoff imo.
It's got to be Star Trek (Next Generation/Deep Space Nine/Early Voyager too) and Battlestar Galactica. I've tried watching The Expanse several times and I have no idea why I can't get into it - everyone recommends it!
On top of a lot of suggestions already here, I really dug Altered Carbon Season 1. Season 2 is good, but Season 1 really slammed it out of the park for me.
I'm surprised no one's mentioned Lost in Space on Netflix. It's a fantastic show about the wonders and dangers of space exploration with great acting, amazing effects and follows a well-constructed story. Only 3 seasons and ends on a lovely little scene.
Stop what you're doing and watch Babylon 5. There's nothing else like it, except DS9 lol. The CGI is terrible but you get used to it. The plot, the writing, the characters, the world building... It's just unparalleled even today.
In general Star Trek, especially Deep Space 9. IMO that show had the perfect mix between story arcs and one-off episodes. It also had one of the best villains of all time in Gul Dukat.
Recently I really enjoyed Andor and The Peripheral. Season 1 of Westworld was also incredible (too bad the quality dropped off in seasons 2 and 3, haven't seen season 4).