#rocket engineering

I’ve been think about the space shuttle again, as one does from time to time at JSC. The shuttle was the symbol of human spaceflight and technology generally during my childhood, so there’s always a certain romanticism to it for me. Nevertheless, it was a complete failure across the original metrics by which the program sold itself, and we should not forget that fact. I want to focus on one of…

I recently made my long-awaited return to Houston, but there’ve been a few snags with IT when it comes to getting my new work computer set up (just your typical government-rules-preventing-the-government-from-doing-government-activities stuff), so I’ve had a bit of dead time to fill during the day. For my own edification, I started plotting the mass values for Mars probes over the years to see if…

Three Ways Technologies Might Not Exist Yet

I’ve been studying spacecraft propulsion for years, and I’ve noticed three different ways in which advanced propulsion concepts are not yet ready for deployment. I think this pattern applies to other technologies, and possibly even outside of technology. For this post, though, I’ll be focusing on rockets because that’s what I know best. The first level I’d call Niven’s 17th Law, which is usually…

Could Starship Really Get to Saturn?

When I wrote my post on propulsion options for missions to the outer solar system, I dismissed an official rendering of SpaceX’s Starship at Saturn as unrealistic. I stand by my basic sentiment—with the chemical propulsion systems that SpaceX has discussed so far, getting a Starship out to Saturn would be impossible without staging propellant at multiple depos in deep space. We’re talking about…

Conflicted on the SLS

We’re less than 24 hours out from the first launch attempt for Artemis 1. After so many years of waiting for the Space Launch System to finally fly, it’s a weird feeling. For over a decade, through delay after delay, space enthusiasts and professionals have been discussing, debating, and analyzing this launch vehicle and the associated systems. It often felt like this point would never come. The…

No Clear Trends in Launch Costs

I started reading LEO on the Cheap over Memorial Day weekend, and after rapidly stalling out, managed to pick it up again yesterday. (Launch vehicles aren’t really my specialty or research interest, but they do impose serious limits on what we can and can’t do, so it’s worth knowing about their capabilities and possibilities.) The book itself is older than I am, which led me to wonder how close…

Propulsion Options for Human Missions to the Outer Planets

I made a subtle mistake when writing my discussion of fast outer planetary transfers—so subtle, in fact, that I didn’t fully realize it until this week. The math is good; I don’t think I made a mistake there. No, the issue was in how I presented the results. Specifically, this figure: Technically, there are two mistakes here: a mass ratio of 100 is frankly ridiculous. I thought that something…