Since 1957 when the first artificial satellite was launched, thousands of spacecraft have orbited Earth. While some are placed into polar orbits for communications or weather purposes, others such as communications satellites orbit in geostationary orbits for longer-term performance. Like throwing a ball into the air creates an unpredictable path towards its landing point, spacecraft…
Have you seen satellites zipping across the sky, taking minutes to travel from horizon to horizon? They appear tranquil but in reality are moving at hundreds of kilometers per second! Satellites help us explore our world and solar system with greater depth. They provide weather forecasts, route cell phone calls, and take pictures of Earth…
All spacecraft require propulsion methods to adjust their velocity. Most propulsion systems possess high specific impulse – that is, how quickly their speed changes per unit of propellant consumed – and are relatively energy efficient. Earth lies deep within a gravitational well, taking 11.2 km/s to escape its gravitational pull; humans can endure much greater…
