TerraChoice also measured green advertising in major magazines and found that between 2006 and 2009, the number mushroomed from about 3.5% of all ads to just over 10%; today, Case says, the number is probably higher still.
NASA bought hydrogen at 98 cents per gallon. A gallon of liquid hydrogen weighs 0.2679 kg, so they paid $3.66 per kg for liquid hydrogen. NASA bought oxygen at 67 cents per gallon. A gallon of liquid oxygen weighs 4.322 kg, so they paid $0.16 per kg for liquid oxygen. 384,071 gallons of liquid hydrogen in the external tank of the shuttle, for a cost of $376,389.58. ~141,750 gallons of liquid oxygen for a cost of $94,972.50. The total cost of all propellant for rocket fuel is $1,380,000. These numbers exclude the hydrogen and oxygen used for cooling, etc.
Top 10 facts about the world. Conventional rockets create thrust by combining liquid fuel with an oxidizer, usually liquid oxygen. Both the fuel and the oxidizer take up a lot of space, resulting in rockets that must be very large to achieve the thrust necessary to launch a satellite into orbit. For example, 8 grams of oxygen is necessary to ignite 1 gram of hydrogen, a typical rocket fuel.