Galactic Suite was founded in 2007 and has recently announced its plan to have the world’s first civilian suite available in orbit for 2012. The website is inviting and gives you lots to dream about. Maybe you really want to see 15 sunrises in a day, or circle the Earth once every 90 minutes. Joining the 450km (280 mile) high club would be pretty cool, something only a few astronauts/cosmonauts have done so far.
As for practicalities, according to the Galactic Suite website the spaceship is said to reach an orbit which is almost as high as a Space Shuttle maximum orbit altitude. The Shuttle is a monster lift-off vehicle with two solid rocket boosters and an Orbiter for a 16-day mission, carrying 24tons (53,300 lb) into low earth orbit, and a maximum of 8 astronauts. It has also cost an estimated US$1.5 billion (€1 billion) a launch.
So Galactic Suite’s rocket plane, which will have the ability to carry 4 tourists and 2 pilots in orbit for a 3 day stay, is a ‘bargain’ for a US$4.4 million (€3 million) ticket price, even if it uses cheaper Russian rockets for the launch.
But what is the environmental impact of spaceflight? Well, it is really tricky to calculate, especially since many rockets use really awful chemicals that have complex compounds that are atrocious on the environment.
The one factor in favor of the space launch is that the atmosphere, or three-quarters of it, is actually only 11kms (6.8 miles) thick. So let’s say the emissions occur within the first 12kms of travel, and ignore all the emissions generated to transport the fuel, design and make the rockets. Then, if we assume the rocket is like the faithful old Soyuz that Russia has used for over 40 years to take people and satellites into orbit, and most recently to the space station, then we can make a reasonable guestimate at the CO2 emissions because the first stage of flight for Soyuz actually uses kerosene which is similar to regular gasoline. Soyuz is used only as an example since it is configured to carry three people only, and is one of the least polluting launch vehicles that can get to orbit. It is not clear exactly what type of launch vehicle Galactic Suites will actually use.
If it takes about 70 seconds to get past the 12km altitude, and assuming a simplified constant burn rate, this means 6,680kgs (14,700lbs) or 8,350 liters (2,200 US gallons) of kerosene is consumed since the Soyuz first stage burn lasts for 118 seconds in total and it holds about 11,260kgs (24,800lbs) of fuel. At around 3kgs of CO2 per liter, that means 25,048kgs (55,200lbs) of CO2 is emitted. That’s a hell of lot of CO2 for six people who are going on a joy ride. Works out to be 4,200kgs (9,260lbs) each, or 6,200kgs (13,700lbs) if you only consider the passengers.
So how does this compare to flying and driving? We all know that flying long distances in a long haul jet is bad for the environment. Assuming about 1kg (2.2lbs) of aviation fuel for every 15kms (9.3miles) flown per passenger, that means about 3kg (6.6lbs) of CO2 is emitted for each 15kms (9.3miles) traveled, not including other emissions such as nitrogen oxides, water vapor and other particulates. If the transatlantic flight is 5,500kms (3,400miles) then the emission per passenger is 1100kgs (2,400lbs) for the flight.
So how about driving your car? Let’s say you drive a Honda Civic hybrid (4.3 litres/100 km (55 mpg US)) then your emissions are about 0.65litres (0.17 US gallons) of gas for every 15kms (9.3 miles), so about 1.5kgs (3.3lbs) of CO2 per 15kms (9.3 miles) traveled. For a 5,500km (3,400 mile) drive that works out at 550kgs (1,200lbs) of CO2 emitted.
Based on the above calculations, spaceflight will be over almost 6 times more polluting than flying in a plane on a transatlantic flight, 11 times more than driving the car, and likely much higher if the true costs were included, especially since neither the plane nor the car are destroyed in the process. The rate at which the CO2 is emitted is almost 8000 higher than for flying.
If the Galactic Suite's enterprise actually does ever get into orbit, then the carbon offsets should be included in the price – it is peanuts compared to the ticket price.
I don’t think there has ever been a carbon neutral spacecraft launch, not even for the environmental spacecraft launched by NASA and ESA. Maybe it is about time they started paying the offsets.
The eight weeks training for the flight on a Caribbean island sounds like a blast and only has the greenhouse gas emissions footprint of a regular vacation. Maybe at the end of it the wannabe galactic travelers can just spend some time in a space simulator, at a cheaper cost to their wallet and to the planet.
Trevor Williams is a University of Victoria Mechanical Engineering PhD candidate specializing in renewable energy, power grid modeling and plug-in hybrid electric vehicles. He has a bachelors in Aeronautical Engineering, a Masters in Management Science and over 23 years international experience in the space industry, having worked on Earth observation and telecommunications satellites. He is the author of the Eco-Geek blog.
Thanks for the observations. The article has been reworked to take account of your comments.
The real cradle-to-grave cost of space flight is actually much higher than can be presented in a short article and a quick illustration. For instance, neither a car, nor a plane are destroyed after their use, unlike an expendable launch vehicle. The CO2 costs to manufacture a launch vehicle for each trip would be enormous.
Even a re-usable launch vehicle has non-recurring launch costs either in drop-off rocket boosters which usually have extremely toxic chemicals, are certainly not kerosene fueled or require 'mother' craft to carry the orbital vehicle to a release altitude. Carrying perhaps a 40 tonne orbiter to 50,000ft would require a lot of aviation gas! Getting to orbit is way more energy intensive than sub-orbital, which is the Virgin Galactic approach. In addition, the higher altitude emissions are very likely to have even more environmental impact than the in-atmosphere emissions, in terms of chemical reactions in the sparse atmosphere.
written by TW , November 09, 2009
Show/Hide comment form
written by Bob , November 09, 2009