Rocket science, explained with soda bottles

Fuel and oxidizer. Together they make propellant, which can be used to launch a rocket – but for the best results, you need to find the right ratio. Too much of one or the other, and your exhaust velocity begins to drop. Less exhaust velocity means less thrust — and less thrust means you will not go to space today. » 4/11/13 4:20pm 4/11/13 4:20pm

How Will Humans Get to Alpha Centauri?

Astronomers have discovered an Earth-sized exoplanet orbiting a star in Alpha Centauri, just 4.3 light-years from Earth. With surface temperatures in excess of 2,000 degrees fahrenheit, this particular planet would be inhospitable, but the fact that it exists at all raises hopes of finding another, more human-friendly… » 10/18/12 8:15am 10/18/12 8:15am