Hacker News new | past | comments | ask | show | jobs | submit login

That is pretty much all there is: If earth was more massive, the chemical rockets we've been producing wouldn't have enough thrust-to-weight ratio to reach orbital velocity (about 25k km/h). We would have to load the rockets with so much fuel to break free of gravity that they would be too heavy to lift themselves.

This is all assuming yields and fuels we have now. If we lived on a more massive earth and we were trying to escape its gravity, I'm sure we'd be using more exotic and dangerous fuels (like all those fun fluorine and boron fuels Dr. Clark mentions in Ignition![0]) to do the job. We just happened to have the capability in the middle of the century to use a fuel we were already making (refined petroleum) for jet engines.

[0] https://www.amazon.com/Ignition-Informal-Propellants-Univers...

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact