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.
The U.S. Energy Information Administration (EIA) estimates fuel prices could drop as low as $2.29 per gallon for gasoline and $2.87 for diesel.