Ad Astra: Breaching Pods

Does this count as stealth?

If you're a fan of science fiction and haven't already been watching The Expanse, do yourself a favour and take a look at the trailer to see what you've been missing. The series is great television, with a gripping storyline and good acting, while also being pretty damn scientifically accurate.

The second season's introductory two-parter involved an assault on an unregistered rotating space station, with an ex-Martian gunship and a cobbled-together Belter transport matched up against a single advanced stealth frigate. One character, Detective Miller, decided to join the assault teams, meaning he has to be on one of the breaching pods that will be launched towards the station. Before we see them on-screen, one character describes them as "a beer can taped to a rocket".

As you can see from the gif, he's not wrong.

Ad Astra: Gravitic Propulsion

What a diametric drive looks like, according to Google

One of the things I've had in the works for a while was a post about gravity manipulation technology as a setting element, how it affects other technologies, daily life, etc. This was originally conceived as a single post but quickly grew too big and unwieldy to be digestible. One of the most mature elements of the post was a discussion of gravitics used for space propulsion.

The standard approach to using gravitic propulsion in GURPS is to just slap reactionless drives on your spacecraft and call it a day. But this misses out on some cool opportunities! So let's take a deeper look at how gravitic propulsion might work.

Ad Astra: New Propulsion Options

Glowing means it goes fast!

I've been playing a lot recently with the rules in the GURPS Spaceships series and have started to see places where I can insert my own rules, make edits, or plug in gaps. I'm working on another two posts in this vein, both thematically linked, but they're not quite done yet. So here are some additional things that aren't really related to one another!

Below are a two new takes on reactionless thrusters, using "real" science (depending on how you define both "real" and "science"), as well as a new superscience reaction drive and two options for antimatter rockets.

Ad Astra: Shift Drive

Ludicrous speed... engage!

For some reason, I love space opera but hate reactionless drives. The two are usually part-and-parcel, since space opera tends to have spacecraft that travel at the speed of plot, but there are some exceptions. But reaction mass limited spaceships creates a problem, in that non-FTL travel inside a star system takes, at absolute best, days. If you want your players to be able to hurry to their ship, burn for escape velocity and dash towards the gas giant moon to save the stranded scientists... reaction drive travel means there's a period of a week or two where they're twiddling their thumbs. Kinda saps the tension out of the scene.

This isn't the end of it – there are plenty of ways to make this kind of timescale work in your setting. But if you want to use more conventional plots and timescales, you need a way for people to travel fast inside a solar system, and that means FTL. But this takes all the fun out of reaction drives! If all they're used for is getting to and from orbit, then they cease to be interesting.

So what if FTL travel requires deltaV too?

Utility Closet: Spaceship Character Sheet

The last campaign I ran was space opera, set in the Endless Space universe. Being space opera, the players had a starship of their very own. It was more than a means of transportation – it was where they hung their hats and charged their power cells, where they slept and kept their stuff, and where they brought their prisoners (my players were quite sensible about not fighting to the death). The main problem of starships is that they have all sorts of statistics and resources to keep track of; power, fuel, reaction mass, rations, weapons, ammunition, etc. It got confusing for me to keep track of these on separate papers or files, so after the campaign ended I drew up plans for a record sheet to use if I ran another space opera game.

I posted it a while ago on the official GURPS forums, with minimal interest shown, though the one person who replied had some very useful input. Now that I have a blog that people seem to read, I thought I'd share it to a wider audience. This is only the second iteration, so I'm mostly looking for feedback, critique and improvements at this point; what more would you want in a spaceships' character sheet? Tables for quick references? More empty boxes for keeping track of miscellaneous things? Have I left out something huge? Obviously there's lots of empty space; my hope is to be able to fill it while keeping the sheet both attractive, simple and clean, and useful. Please let me know in the comments!

Ad Astra: Singularity Rider

Horrible cosmic deathtrap or delicious
starship power supply?

It's a new column! And it's not the one I mentioned before! Surprise!

Just about the only promising way for humans to travel the vast distances between stars within a lifetime is the black hole starship. The basic operating principle is simple and also totally nuts. You collapse matter to make a black hole massing in at around 606 kilotons. Given it's so small, it releases intense Hawking radiation – this can be deflected out the back to provide thrust directly or used to heat reaction mass. Estimates of power output place black hole drives as being able to accelerate to 10% of lightspeed in about 20 days. Assuming a uniform acceleration rate (which is wrong due to relativity but a decent approximation), you could get to near-lightspeed in just under seven months.

Once you can get going that fast that quickly, the galaxy opens up a lot. Travel times are still measured in decades but at such a high fraction of lightspeed, time on-board the starship goes slower, so you could feasibly travel anywhere within a few hundred lightyears in only a few years (from your perspective).

So let's build one in GURPS Spaceships!