|In space, no one can hear you squee.|
So, rather than strain to pick the best geeks in all of horror, let's focus on the astronomical aspect. This is the way to go because May 25th is also the anniversary of It Came From Outer Space and Alien.
I haven't seen the 1953 classic, but Ridley Scott's 1979 tour de force is a true and pure horror film, despite what anyone says about its roots in action or science fiction. People who make that argument are likely suffering from a distorted memory caused by their feelings about the sequel, Aliens, which drops the slow, suspenseful walks through dark hallways in favor of big flashy gun fights in dark hallways. The deaths in Alien are terrifying. The infamous birth scene remains one of the most iconic jump scares ever put on screen. When you realize, along with the crew, that the alien's blood is burning through the floor of the ship, the weight of the situation is crushing. These people are fucked.
Two films do not constitute a marathon, but luckily we have a wealth of choices to fill out the gaps in an alien marathon. We've seen many of these on HorrorClix TV, since it seems to be a favorite topic of channel moderator Flapper_Jane. UFO documentaries are a solid choice if you can handle a few cups of bullshit, but I think we can easily make a list of films without even having to rely too much on the obvious picks.
Alien Abduction: Incident in Lake County provides an example of "early" found footage, being released in 1998, one year before The Blair Witch Project made the subgenre a bona fide fad. Presented as one of the aforementioned documentaries, it is rife with overblown acting and shoddy camera work, and that's the way I like it. It's also exceptionally dark, with the justification being (if I remember correctly) that the alien technology had either drained all the power from the area or was somehow interfering with the flow of electricity.
Fire in the Sky may be considered an obvious pick for some, but until a few years ago I just knew it as "holy fuck that one really fucked up thing I saw on TV one night when I woke up at like 4 in the morning when I was a kid". Specifically, I turned on the television after waking up in the middle of the night only to see the abduction and experimentation scene, in which a strange rubbery substance is stretched over the protagonist and vacuum shrunk to fit his form and things only get scarier from there. If you haven't seen this visually stunning flick based on an allegedly true story of alien abduction, please treat yourself. You will fear the heavens once more.
Attack the Block garnered moderate to strong hype when it released a few years ago, but I can assure you that it deserved every bit of it. Unlike the other entries on this list, which mostly strive to build suspense and terror, Attack the Block is a lighthearted action sci fi romp. The heroes are a gang of urban British teens who rob teachers, get in fights and kill what they assume to be a wild animal until they realize that, oops, it's actually a raging gorilla-like alien with giant glowing fangs as its only facial feature. And boy, does it have a lot of 'em. And boy, are there more than one of these things. Violence, romance, a heaping helping of weed and a wonderfully British sense of humor mark this alien adventure featuring Nick Frost of Shaun of the Dead fame.