A CITY ON MARS
by Kelly Weinersmith and Zach Weinersmith
Earth is not well. The promise of starting life anew somewhere far, far away—no climate change, no war, no Twitter—beckons, and settling the stars finally seems within our grasp. Or is it? Critically acclaimed, bestselling authors Kelly and Zach Weinersmith set out to write the essential guide to a glorious future of space settlements, but after years of research, they aren’t so sure it’s a good idea. Space technologies and space business are progressing fast, but we lack the knowledge needed to have space kids, build space farms, and create space nations in a way that doesn’t spark conflict back home. In a world hurtling toward human expansion into space, A City on Mars investigates whether the dream of new worlds won’t create nightmares, both for settlers and the people they leave behind. In the process, the Weinersmiths answer every question about space you’ve ever wondered about, and many you’ve never considered.

“Scientific, educational, and fun as hell.”

— Andy Weir, New York Times bestselling author of The Martian and Project Hail Mary

“There is simply no more engrossing, entertaining, or thorough way to understand the intense challenge of humanity's off-Earth future than A City on Mars. I LAUGHED THE WHOLE WAY THROUGH.”

— Hank Green, New York Times bestselling author of An Absolutely Remarkable Thing

“Listen up, humans. How to poop in space will be the least of our concerns. Herein are challenges most space-heads, including me, never even considered: not just technological, but legal, ethical, geopolitical. Despite the breadth and depth of research and some impressive near-wonk-level detail, this is a clear, lively, and hilarious read. Slam dunk, Weinersmiths!”

— Mary Roach, New York Times bestselling author of Fuzz and Packing for Mars

"A City on Mars is deeply researched, hilarious, and sobering. Zach and Kelly Weinersmith have given us a bracing to-do list for the new age of space. Highly, highly recommended.”

— James S.A. Corey, author of The Expanse series

Praise for A City on Mars

“This might be the best book ever written about humans in space, or at least the funniest. I don’t know of anything else quite like it: an extended, comical confrontation between the dreams of space colonies and the gross, dangerous, tedious realities. Read it before you go.”

— Scott Aaronson, Schlumberger Chair of Computer Science and Director of Quantum Information Center, University of Texas at Austin

“Of the many books and extensive literature on Space mission architectures, technical and otherwise, this is the only one that is a must-read to understand the deep financial, physiological and technical constraints of one of the largest and most ambitious endeavors of our time: enabling humans to become a multi-planetary species.”

— Professor Sinead O’Sullivan, member of the Advisory Council of the European Space Policy Institute

“A fun, and sobering, exploration of what it means to explore beyond our planetary home. Sure, the stars beckon and TV shows and movies make space travel seem like a blast, but before you invest in another billionaire’s crypto-powered Mars colonization dream, you might want to pick up this book and learn about the risks, astronomical costs and thorny ethical issues involved. The Weinersmiths take you on a journey to our unlikely future on other planets with impressive detail, eye-opening facts, and extremely funny cartoons.”

— Jorge Cham, author of Oliver’s Great Big Universe and creator of PHD Comics

“Earth may not be perfect, but we evolved here. Everywhere else in the Universe will try heartily to kill you in nasty ways. The Weinersmiths logically and patiently lay out the case that if we want to live in space, there’s a lot of ground work to do first. If you’re a gung-ho Moon and Mars enthusiast, this book will show you why it’s best to slow down the space race just a bit.”

— Phil Plait, writer of the “Bad Astronomy Newsletter”

About the Book

From the bestselling authors of Soonish, a brilliant and hilarious off-world investigation into space settlement

Can you make babies in space? Should corporations govern space settlements? What about space war? Are we headed for a housing crisis on the Moon’s Peaks of Eternal Light—and what happens if you’re left in the Craters of Eternal Darkness? Why do astronauts love taco sauce? Speaking of meals, what’s the legal status of space cannibalism?

With deep expertise, a winning sense of humor, and art from the beloved creator of Saturday Morning Breakfast Cereal, the Weinersmiths investigate perhaps the biggest questions humanity will ever ask itself—whether and how to become multiplanetary.

Get in, we’re going to Mars.

About the Authors

Dr. Kelly Weinersmith received her PhD in Ecology at the University of California Davis, and is an adjunct faculty member in the BioSciences Department at Rice University. Kelly studies parasites that manipulate the behavior of their hosts, and her research has been featured in The Atlantic, National Geographic, BBC World, Science, and Nature. When she isn’t studying Nature’s creepiest wonders, Kelly is writing books with her husband, Zach Weinersmith (creator of Saturday Morning Breakfast Cereal Comics). Their first book, Soonish: Ten Emerging Technologies That’ll Improve and/or Ruin Everything, was a New York Times Bestseller.


Zach Weinersmith is the cartoonist behind the popular geek webcomic, Saturday Morning Breakfast Cereal. He co-wrote the New York Times bestseller Soonish: Ten Emerging Technologies That’ll Improve and/or Ruin Everything and illustrated the New York Times-bestselling Open Borders: The Science and Ethics of Immigration. His work has been featured by The Economist, The Wall Street Journal, Slate, Forbes, Science Friday, Foreign Policy, PBS, Boingboing, the Freakonomics Blog, the RadioLab blog, Entertainment Weekly, Mother Jones, CNN, Discovery Magazine, Nautilus and more. He lives in Virginia with his wife/coauthor and his children/coauthors.

About the Authors

Dr. Kelly Weinersmith received her PhD in Ecology at the University of California Davis, and is an adjunct faculty member in the BioSciences Department at Rice University. Kelly studies parasites that manipulate the behavior of their hosts, and her research has been featured in The Atlantic, National Geographic, BBC World, Science, and Nature. When she isn’t studying Nature’s creepiest wonders, Kelly is writing books with her husband, Zach Weinersmith (creator of Saturday Morning Breakfast Cereal Comics). Their first book, Soonish: Ten Emerging Technologies That’ll Improve and/or Ruin Everything, was a New York Times Bestseller.


Zach Weinersmith is the cartoonist behind the popular geek webcomic, Saturday Morning Breakfast Cereal. He co-wrote the New York Times bestseller Soonish: Ten Emerging Technologies That’ll Improve and/or Ruin Everything and illustrated the New York Times-bestselling Open Borders: The Science and Ethics of Immigration. His work has been featured by The Economist, The Wall Street Journal, Slate, Forbes, Science Friday, Foreign Policy, PBS, Boingboing, the Freakonomics Blog, the RadioLab blog, Entertainment Weekly, Mother Jones, CNN, Discovery Magazine, Nautilus and more. He lives in Virginia with his wife/coauthor and his children/coauthors.