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Blog Series: Countering misconceptions in space journalism

As a lover of all things space I enjoy reading a wide variety of perspectives. The more different the origin, the more likely I am to learn something new! Even in articles which contain errors or elements of confusion, there’s still a good chance that I’ll encounter a new way of thinking about an issue. This is important. Space is hard, and it’s also hard to reason about. Humans often prefer reasoning by analogy, but with very few exceptions, reasoning by analogy in space is always wrong. So we need to find other ways to reason about space systems, architectures, … Continue reading Blog Series: Countering misconceptions in space journalism

So you want to build a carbon capture company

Would you like to win one hundred million bucks from Elon Musk? Carbon capture (CC) is all the rage these days, with dozens of companies springing up to remove CO2 from the atmosphere and help stabilize the climate. I am not an expert on carbon capture but I do get asked about it from time to time. As a public service, therefore, I am offering the following rubric as a means to organize our thoughts, refine our strategy, and champion quantitative rigor when it comes to developing and evaluating a wide variety of carbon capture systems.  Is our carbon capture … Continue reading So you want to build a carbon capture company

Powering the Lunar Base

NASA’s selection of SpaceX’s Starship within the Human Lander System (HLS) program was both surprising and exciting for space nerds all over. Previously I have written about how Starship’s ambitious approach could transform the Artemis Program, particularly since Starship’s excessive cargo payload capacity creates a lot of opportunities that were previously curtailed by the harsh reality of razor thin Lunar mass budgets. As a rough rule of thumb, conventional approaches to Lunar transportation put cargo costs at upwards of $100m/T, while Starship should be able to get as low as $1m/T without any miracles, and perhaps as low as $100k/T … Continue reading Powering the Lunar Base

“The Martian” + Starship

“The Martian” by Andy Weir, and its film adaptation directed by Ridley Scott, remain some of my all time favorite science fiction works. Way back in the day I wrote a technical commentary. I last read the book in 2015 (until 2 weeks ago) and watched the film in 2018. More recently I’ve been exploring in detail how Starship changes the game with Lunar exploration and began to wonder what “The Martian” would look like with a Starship-based architecture, rather than the rather more expensive and complex architecture used in the book. If you haven’t read the book, do so … Continue reading “The Martian” + Starship

Lunar Starship and unnecessary operational complexity

This blog addresses the question of how SpaceX’s Starship could be used to ferry people and cargo to and from the Moon under a variety of different situations. It follows on from previous posts on Starship and Artemis, and Starship as a mechanism for space transport post scarcity. Broadly speaking, by the end of this post the reader should have a good idea of the variables and cost/benefit for various Starship-enabled transport systems. It’s worth stating at the outset that Starship is in a league of its own in the current field of lunar landers. Within the HLS program, the … Continue reading Lunar Starship and unnecessary operational complexity


This is a short, weird blog describing an experiment in travel story telling. During my misspent youth I did a lot of backpacking and hitchhiking. Here’s an index of trips, accounts, photos. I was largely inspired by the accounts of Vladimir Dinets, an accomplished zoologist who later became a friend and mentor. I’ve always been a map nerd and, largely stuck at home through most of 2020, I decided to revisit ideas I’d long been exploring about combining geographically relevant text-based narrative accounts with the wild data capacities of Google Earth. While cataloging my travel diaries I realized one was … Continue reading Geodiaries

Sea voyages

Recently I polled Twitter for outrageous sailing adventure stories. Here is a list of replies. If you have any others to include, please leave in comments. Alain Bombard crossed the Atlantic in 1952 in an open Zodiac with no supplies. Tim Severin and crew crossed the Atlantic in a leather coracle in 1976. David Lewis sailed to Antarctica in a small yacht in 1972. 1986 crossing the Atlantic in a Hobie cat. Tim Anderson’s attempting migration to Cuba. Someone sailed an open dinghy, solo, from Mexico to Tahiti in 214 or so days. Lost the link. The Batavia (1628). 1152 … Continue reading Sea voyages

Predictions 2021: Prospective

My previous blog was on retrospective predictions. Of course there’s selection bias but I tried to make sure that I picked at least a few that I did terribly with. This blog is prospective. Future looking. As of March 5, 2021. I crowd sourced some questions. If you have any more, leave them in the comments and I’ll add them, with the appropriate dates and commentary. In a year or so I’ll do another fresh blog and grade myself. Nuclear fusion propulsion is probably necessary for human travel to the outer solar system or other stars. It might work a … Continue reading Predictions 2021: Prospective

Predictions: Retrospective

Prediction blogs seem to be in vogue. I suppose the idea is if you can demonstrate a track record of correct predictions then maybe you have some real insight? Or got lucky a few times? In any case, making bad predictions would seem to indicate poor insight. So I’m going to do two prediction blogs. This one is retrospective. I’m mining my past public statements for predictions and grading them on accuracy. The next one is prospective, talking about stuff that’s coming up or things that people have asked me. Starship architectureIn January 2017, I published a book on transport … Continue reading Predictions: Retrospective

SLS: What now?

“Okay, wise guy, the SLS hasn’t turned out, everyone knows that, what do we do now?” Quoth some person on the internet. This blog is a followup to my previous post on the SLS and its fundamentally compromised architecture. I have been pleasantly surprised by positive responses and feel that I might have gotten closer to the mark than I at first thought. Indeed, not one week later, former JSC director George Abbey wrote a policy paper focusing on SLS’s excessive costs. The SLS is both a cause and symptom of deeply challenging issues within US space flight, and identifying … Continue reading SLS: What now?