SpaceX receives first-ever FAA license for commercial reentry • Hacker News Board

Re: SpaceX receives first-ever FAA license for commercial reentry

#21

Post by JabavuAdams » Tue, Nov 23, 2010, 3:02 PM UTC

electromagnetic wrote: post #2

This is quite simply amazing news. The implications are astounding, beyond the mere selfish prospect of one day travelling to space as a tourist. Considering a loose estimate on the value of the asteroid belt is like $5(10^20), it could literally be a new gold rush. It would be awesome (to the true definition of the word) if one day our manufactured goods are being landed from space rather than shipped across the oce…

I agree with the sentiment, but there are some practical problems.

Barring a machine intelligence explosion in the next half-century, we'll probably be getting to orbit on rockets.

Nitrous oxide and methane are two big greenhouse gasses. So to get to space, we're going to have to dump a whole lot more of this stuff into the atmosphere.

Note, I haven't run the numbers, so I may well sound like an idiot by noon.

Re: SpaceX receives first-ever FAA license for commercial reentry

#22

Post by JabavuAdams » Tue, Nov 23, 2010, 3:08 PM UTC

burgerbrain wrote: post #4

I firmly believe that SpaceX is the best chance humanity currently has at achieving space travel for the general population. They are one of the few companies I can get honestly excited about these days.

> I firmly believe that SpaceX is the best chance humanity currently has at achieving space travel for the general population.

No. Although they're technically impressive, they have spent defense contractor amounts of money to get where they are today. There's almost no chance that this will help the general population get into space, except perhaps by testing the regulatory system.

Check out XCor, Masten, Armadillo, Scaled Composites if you're interested in personal access to space.

> hey are one of the few companies I can get honestly excited about these days.

Agreed.

Re: SpaceX receives first-ever FAA license for commercial reentry

#23

Post by jerf » Tue, Nov 23, 2010, 4:23 PM UTC

JabavuAdams wrote: post #21

electromagnetic wrote: post #2

This is quite simply amazing news. The implications are astounding, beyond the mere selfish prospect of one day travelling to space as a tourist. Considering a loose estimate on the value of the asteroid belt is like $5(10^20), it could literally be a new gold rush. It would be awesome (to the true definition of the word) if one day our manufactured goods are being landed from space rather than shipped across the oce…

I agree with the sentiment, but there are some practical problems. Barring a machine intelligence explosion in the next half-century, we'll probably be getting to orbit on rockets. Nitrous oxide and methane are two big greenhouse gasses. So to get to space, we're going to have to dump a whole lot more of this stuff into the atmosphere. Note, I haven't run the numbers, so I may well sound like an idiot by noon.

Not all rocket fuels are the same. Falcon 9 appears to run on kerosene and LOX, which combusts into H2O and CO2. H20 is all but a noop (technically a greenhouse gas but cycles very quickly and you're not going to affect the net balance with a rocket), and while the CO2 may be a concern, bear in mind that as big as a rocket may be visually it isn't necessarily a big contributor relative to the rest of the industrialized planet as a whole.

Also, remember that one of the things a practical commercial space program will do is start mining the asteroid belt for rare earth metals, many of which are needed for green technologies. For instance, one problem with fuel cells is that there isn't enough platinum on Earth to make them for everybody. It is not hard to spin the math such that private spaceflight could be one of the greenest things to ever happen to industry. (And I felt I should be honest about the word "spin", but there is a truth there too. One must make full accountings to decide whether something is good, not count up the costs, ignore the benefits, and make grand pronouncements.)

Re: SpaceX receives first-ever FAA license for commercial reentry

#24

Post by lucasjung » Tue, Nov 23, 2010, 4:34 PM UTC

yellowbkpk wrote: post #20

lucasjung wrote: post #8

Earlier quoted context omitted.

No, but they regulate the part where a chunk of white-hot metal and composite plummets into an area of the sky they're responsible for. That extends well beyond U.S. territorial airspace--by international agreements, much international airspace has been assigned to various nations to control. If SpaceX were to conduct their entire reentry out in the middle of the pacific in completely uncontrolled areas then they pro…

Do they also require a license to exit the planet through said airspace? Is it possible to receive one but not the other? i.e. If by some clerical error SpaceX received their "Exit License" but then forgot their "Re-Entry License", would the capsule then be stuck in the outer atmosphere? Pedantic, I know, but still oddly intriguing to me. The fact that such a legacy organization like the FAA has to stretch to fit int…

They do need a license to launch, and such licenses are very common: commercial satellite launches happen all of the time. The FAA needs to be involved because those rockets pass through controlled airspace on the way up and the FAA needs to take measures to keep aircraft away from them. This is news because, for the first time, a commercial entity is going to attempt to bring something back from orbit instead of just sending it up and leaving it there.

Reading between the lines, SpaceShipOne apparently didn't need a re-entry license, probably because they never achieved orbit and so their return didn't meet some technical criteria to be considered a "re-entry" by the FAA. They probably had some sort of special license from the FAA, though.

Re: SpaceX receives first-ever FAA license for commercial reentry

#25

Post by jballanc » Thu, Nov 25, 2010, 1:18 AM UTC

iwr wrote: post #19

brc wrote: post #16

Earlier quoted context omitted.

I wonder, though, if the same problems will apply : high per-passenger-mile costs and restricted takeoff/landing sites. Eventually the Concorde overcame the per-passenger-mile costs but they could never evade the takeoff and landing restrictions. If they had flown the LA/NY route it would have been much more successful. I can see any type of space transportation coming across the same issues.

While flying twice as high as passanger aircraft, the sonic boom would still be a problem with the Concorde. The restriction would be greatly reduced with a suborbital plane, which cruises outside the atmosphere.

This. There are some real benefits to not having to fly through air the whole way.