One of my bugbears about discussions of terraforming Mars really: any atmosphere we added to the planet to give it substantial surface pressure would take hundr

One of my bugbears about discussions of terraforming Mars really: any atmosphere we added to the planet to give it substantial surface pressure would take hundreds of thousands of years minimum to be lost in any quantity (i.e. by redirecting water ice comets to bombard it with Earth's ocean levels of new gases). Atmospheric loss just isn't a problem compared to the technical challenge of doing the comet redirect (which is actually the most plausible part of the enterprise, compared to the monster which would be developing an ecosystem on a barren planet that stabilizes at a human-habitable point of usefulness and isn't just "walls of sulfur algae" for a few thousand years.