I don't want to downplay SpaceX at all because I'm a huge fan, but isn't flying someone to the moon (and presumably back) more complicated than just flying around the moon and back? As I understand, apart from the challenge of achieving orbital velocity (no small feat), flying around the moon might require ~41% more velocity (assuming escape velocity to orbital velocity being a ratio of something like sqrt(2):1) and you can use the moon's gravity to redirect you back to earth, whereas landing on the moon and returning requires even more energy (slowing down to land + escaping the moon and returning), not to mention the various other technical requirements involved with the landing itself.
"Beyond the moon" makes this sound like it'll be a greater achievement than the Apollo moon landings, but I'm not sure that's really true. Don't get me wrong, the fact that it's a private (ish) company doing this is incredible, just not quite "moon landing" incredible... yet.
https://en.wikipedia.org/wiki/Lunar_orbit_rendezvous
so they would need to return to the Earth directly from the surface of the moon
https://en.wikipedia.org/wiki/Direct_ascent
Direct ascent requires a much larger initial launch mass, i.e., a larger rocket than has ever been built. Since it took the massive Saturn V to complete the Apollo missions using lunar rendezvous, and SpaceX's Falcon Heavy is smaller, I don't think they are even close to having the ability to land on the moon and return.
(And that's assuming there's not other insurmountable factors preventing Dragon from landing on the moon and taking off, which there probably are.)
Hopefully someone with more knowledge can chime in.
On the upside, they can land an un-manned assent vehicle on the surface of Moon / Mars before sending people there. Which can significantly increase your odds of getting back.
PS: Yes, NASA did get to the moon and back several times, but they also took a massive chunk of US GDP to do so. https://en.wikipedia.org/wiki/Budget_of_NASA#/media/File:NAS...
1. https://en.wikipedia.org/wiki/Docking_and_berthing_of_spacec...
2. http://space.stackexchange.com/questions/13665/what-is-the-d...
The only craft SpaceX has that can land on Earth or the Moon is Dragon. I am pretty sure Dragon does not have enough delta-v to do a full propulsive landing on the moon (no aerobraking available) and then return to orbit. And they definitely don't have the tech to re-fuel in lunar orbit for the return to Earth. None of this equipment exists.
Not to mention that this would be a totally new lunar strategy, since the Apollo mission returned to earth in the lunar orbiter (Command Module) rather than re-fueling and returning in the lunar lander.
The information I'm finding on the internet suggests Dragon 2 should run around 400 m/s of delta-V (it only needs on the order of 200 m/s to go from terminal velocity aerobraking to landed on Earth).
TLI to LLO is 800 m/s, and I'd guess that a Circumlunar return trajectory to LLO transfer would be on that order -- which is already out of the Dragon 2's range and you're only trying to get into orbit on the Moon, not return, and definitely not land or take off again.
Its close enough though that a beefed up Dragon 3 might be able to dock with some kind of space station and refueling dock in lunar orbit, then you just need to have a lunar ferry (Apollo sorta downsized all of this and crammed it all on top of a Saturn V for one-time use -- I'm thinking a bit bigger for the whole system and more cough reusable...)
However, the minimum delta V to land on the moon is ~1.72 km/s, and you need another 1.72 km/s to get back into orbit + some safety factor ~2.2-2.4 km/s. By comparison it takes ~8km/s to get from LEO to low moon orbit and back to earth. Though you can reduce this by how hard to hit the earth's atmosphere. So, having fuel to land and take off from the moon is not that much worse than getting to the moon and back.
No, from Earth LEO some 3.1 km/s will get you to TLO, and then some ~1 km/s will take you to Moon low orbit, so total about 4(+) km/s. 8 km/s is an approximate budget for a round-trip between low orbits.
Sending a couple of humans around moon for tourism is a waste of resources.
See: Apollo 8 mission.
Though I don't know why anyone would want to spend a week locked in a tiny can like that, let alone pay big bucks for it. There's a limit to the discomfort I'd be willing to endure for bragging rights.
People tend to think of the Moon as a "staging point" on the way to Mars, but in reality, it would be a significant detour.
One persons waste of resources is another persons revenue. They're not doing it for charity.
ULA has a great writeup of how you might do this if you have on orbit refueling capabilities.
And on the one hand it seems like total science fiction but on the other, Elon is talking about next year.
In fact, a permanently-in-orbit transfer vehicle might make sense here; have this vehicle run the actual Earth<->Mars transfers, then just shuttle in fuel/supplies/crew on each Earth arrival.
Either way, a Falcon-like reusable launch system makes plenty of sense here in terms of making this sort of thing possible.
Buzz Aldrin is a big proponent of this approach: https://buzzaldrin.com/space-vision/rocket_science/aldrin-ma...
Evidently this problem is solved, because liquid fuel rockets have been working fine in space since the 60s. (Liquid fuel rockets have their propellants pumped into the chamber.)
> nominal bleed off from warming
Launch the tanker just beforehand. There won't be time for the fuel to bleed off.
Ullage motors are used to settle the fuel at the bottom of the tanks, so the main motor pumps can get to it.
Once the main motor starts providing acceleration, the ullage motors are no longer required.
For cross tanking, keeping the ullage motors running for long enough to transfer all the fuel, without the main motors running might be prohibitive.
The saturn 5 used small solid rockets as ullage motors. Alternatively you could use externally pressurised bladder tanks for a range of non-cryogenic fuels. Cold gas or possibly h2o2 as a monopropellant come to mind. Either option has a comparatively low specific impulse, so even running them at very low overall accelerations for extended time periods is likely to be cost-prohibitive.
I like the suggestion elsewhere of spinning the tank. You could also dock, then spin the whole combination ship. If you abandon the fuel station idea, you could just take the extra fuel tank with you, transferring fuel to your internal tank during a main engine burn, then abandoning the empty tank in a wierd orbit.
The idea of docking modular components in space is a good one though. Perhaps all you really need to do is lift a bunch of fuel tanks since there is plenty of time to perform burns with smaller boosters on longer distance trips.
Worse, the extra steps involved create extra risk, both for mission failure and to the lives of the crew. You could get to your fuel depot and discover the battery sytem has failed and your depot is tumbling, or a leak caused ice buildup that prevents you from docking. Or the chillers failed and enough oxydizer got vented into space that you can't continue the mission.
Why not? Their Dragon capsules can dock with the ISS; why wouldn't they be able to dock with each, possibly with some kind of adapter? You can imagine one Dragon and a trunk docking with another upper stage that's all fuel tank, heading to the Moon, undocking in orbit, landing, ascending, and rendezvousing in orbit to return home.
The total dv requirements of landing on the Moon and ascending again starting from low Moon orbit is 4 km/s. I haven't done the math, but I suspect that you can put together a workable mission using two Falcon Heavy launches. Now, granted, they don't have all the exact pieces put together quite yet, but I suspect they've been thinking about it.
Of course it's laughably overkill for the purpose -- amateur radio operators using much smaller equipment can already send and receive signals to each other by bouncing them off the Moon, which has four times the signal attenuation owing to the doubled distance plus a good deal more in losses from the poor reflectivity of the Moon to radio waves.
Or to put it differently, the difference is that when you get to the Moon you make an orbital injection burn in order to slow yourself down to the point that you can stay in lunar orbit, and then when your done you make another burn to put you back into the trans-lunar orbit.
When you get back you can either do a high speed re-entry or you can do an Earth orbit injection burn.
You still need a vehicle that can carry people for the duration of the trip. You need to get it into a translunar orbit so that you can get out to the Moon. You need to be able to precisely locate yourself in space relative to the Earth-Moon system and course correct to achieve your orbit goals. All of that stuff has to happen either way.
There is an excellent discussion of the various orbit options for getting to the moon in this paper: http://www.esa.int/esapub/bulletin/bullet103/biesbroek103.pd... definitely worth looking over to get a better appreciation on what is involved.
We sure have different definitions of "delivering".
Look at SpaceX as an example of what happens when someone fumbles the ball so hard it takes over four decades to recover it. Virtually nothing happened in that time other than the shuttle program, and that was never intended for travel outside of Earth orbit.
Now we're finally back to innovating and engineering for actual space travel.
Consider an America with the Texas Collider operational where major discoveries were made a decade before the CERN one even existed.
Consider an America where the ARPA internet project could have been one of the least notable breakthroughs in the last thirty years.
Just imagine how economical space flight would be if all of that 1960s technology had been incrementally improved on for efficiency, manufacturing ease, and scale instead of a lot of it being almost literallly mothballed.
"Once operational Crew Dragon missions are underway for NASA, SpaceX will launch the private mission on a journey to circumnavigate the moon and return to Earth."
I don't know why people are arguing over whether they are landing or not...
Note that the press release says:
Most importantly, we would like to thank NASA, without whom this would not be possible. NASA’s Commercial Crew Program, which provided most of the funding for Dragon 2 development, is a key enabler for this mission.
Your tax dollars, if you are American, helped pay for this. Thank you and congratulations - if it works out; if not, was it worth the risk?
EDIT: In response to many below, remember that the U.S. military isn't the only alternative use of the money. Taxpayers could keep it, or it could go to other programs such as education and health. (Personally, I'd happily pay more taxes for more space exploration, education, health, and military necessary for security.)
And with that money they are getting two different spacecraft that can fly missions. So I think it was a great way for NASA to contract out the development of a crew capsule they could use on their missions.
That one of the companies that participated has done so in such a way that they can make a commercially feasible 'tourist' vehicle out of it? That blows my mind.
[1] https://www.nasa.gov/sites/default/files/files/NASA_FY_2016_...
If we establish a permanent Mars colony, that would really increase security for all of mankind.
Building more nuclear weapons is NOT increasing security.
> every time you convince someone that manned space doesn't make sense you convince them there's no reason to go into space at all
Yes, my tax dollars going towards research (even indirectly) is better than the way most of my money is spent
Penicillin, for one, was discovered over a decade prior to WWII. A method of mass production was developed in 1940, but have no idea how much that had to do with the war.
The sixties-era DARPA method: throw a bunch of defense money at a bunch of really smart people without getting too specific about how much of the research should proceed.
But that makes no sense.
yes
On edit: meant for the parent comment, but its parent instead
No. That's a common misconception. ICs were a commercial development, and microprocessors came from the calculator industry.
Pre-IC electronics miniaturization was pushed hard by the USAF; NASA just used it. The USAF had a flyable transistorized computer in 1954, before NASA existed. The Minuteman I missile (1962) carried a transistorized guidance computer.
On the other hand, I doubt we spend much money upgrading our ICBMs. The technology is mature, and that's an area where "good enough" is, well, good enough.
(There at least used to be a Minuteman silo with the door painted like a pizza box with that slogan)
And that is something we all need to think long and hard about. Sure, spaceflight is cheaper these days, but we also live in an age of extraordinarily concentrated wealth. The necessary implication of individuals with power enough to rival governments is that, well, they can rival governments.
Anyone else see that giant superyacht in london? The one that used HMS Belfast as a dock. Some really do have toys to rival governments.
https://www.thesun.co.uk/wp-content/uploads/2016/09/nintchdb...
Do you think this is a bad thing? Personally I quite like the idea of having enough wealth / power to rival a nation-state, since I trust the average nation-state exactly as far as I can throw it.
In contrast, most governments have acquired massive wealth through taxation of their subjects. Those subjects are less likely to tolerate the burden of taxation without some form of reciprocal obligation by the government, such as the expectation they will feed starving children, or provide for common defense, or ensure the viability of comprehensive health care systems.
The feat of the self-made ultrawealthy individual is magnified by the possibility that they have also paid taxes while accumulating their wealth.
In the case of Musk, he appears to have earned his fortune via normal entrepreneurship and standard business practices. He has contributed to giving us Internet payment services, private orbital launch, electric cars, solar energy production, and a few other things that (presumably) enough people want to make a business of them. The theoretical check on the serial entrepreneur that has achieved escape velocity from the rat race in both figurative and literal senses is starting a new business from old exit money that eventually fails hard.
I don't want Musk to feed starving children on Earth. I want him to feed children on Mars. If he can do that, I will likely throw fistfuls of my money at his face without him having to wave a gun in mine.
But he does seem to be a rather rare breed. Many ultrawealthy people did not accumulate their wealth by fulfilling the wishes of others. If you compare the likes of Musk, Gates, and Buffett with corrupt heads of state (i.e. Vladimir Putin) and monarchs, where the personal wealth is siphoned off from government funds, those are the people who most need some form of theoretical check. Those two classes don't need to be held to the same standard, because there is a vast gulf separating wealth that was earned from wealth that was taken.
There are billion-dollar founder-managers. There are billion-dollar investor-board members. People like Carl Icahn blur a bit of the line between passive and active income, but changing the direction of a company via votes and proxies is work, too. Even managing a hedge fund involves some work, as it involves calculating alpha, beta, and correlation rather than direct management of one company, but that's applying a lot of information-leverage to a little bit of work, and I consider that to be mostly passive income. The work itself is worth maybe $100k to $500k/year for the financial analysis, and any excess is passively gathered as dividends from the portfolio companies and as fees from the fund's investors.
It isn't a binary "good rich" and "bad rich". There is a continuous spectrum from not a dime that wasn't earned to not a dime that was. The tech company tycoons fall mostly on one end of that, and the Saudi princes fall mostly on the other.
I think that as a gross generalization, those who have had to earn some of their wealth have a greater right to spend what they have as they please, without consideration for societal expectations. There's no noblesse oblige for the person who does not passively benefit from the collection of the taxes.
But if you're a wealthy monarch, or a trust fund baby, you had damned well better think of the children before you try to go to space.
That isnt always true, but at least there are elections.
The last of which got us Donald Freaking Trump, Jeff Sessions, Kellyanne Conway, and the other Stooges.
Practically speaking, there isn't anything the UN can do if America sticks a base on Mars and calls it sovereign soil. We've already started legalising private ownership of celestial bodies through the SPACE Act, in direct contravention of the Outer Space Treaty.
>It is the sense of Congress that by the enactment of this Act, the United States does not thereby assert sovereignty or sovereign or exclusive rights or jurisdiction over, or the ownership of, any celestial body
See also the Russian bases in the Australian Antarctic territory. Australia asserts sovereignty over a third of Antarctica, Russia ignores it and sets up bases anyway. Australia has neither the ability nor the desire to fight Russia, so we studiously ignore it.
I don't think it is fair to compare the SpaceX plan with China's (who have almost certainly had to acquire the expertise from a starting position far, far behind where SpaceX started).
China was the beneficiary of decades of Soviet research into space as well, their early program flew Soyuz craft, their current craft maintain backwards compatibility if what is available is to be believed. They have a space station and put a rover on the Moon. So how is that an unfair comparison?
And how does using existing research take away from anything SpaceX has done? Sure NASA bought missions from them before they were sure that they could deliver, that sort of seed funding is not uncommon. Blue Origin benefited from a wealth of data in the DC-X project, also funded by NASA but its still remarkable what that they took Newshepard up and down from space four times.
I disagree that the Chinese started from scratch. From where I am sitting they started at the exact same place SpaceX did, using the research and know-how from a well funded and storied space organization to bootstrap their goals.
We can count it different ways. Besides having millenias long history of rocketry, China modern space program started with von Karman student:
So what? Nobody reinvents the wheel if they don't have to.
And I don't know why you think China started behind SpaceX. China benefited from US technical assistance in a way that SpaceX didn't.
Not if you count de-orbiting as part of landing it doesn't. It has something like 300m/s dV. Landing would take 2000ish, and that just gets you down.
That is scary, and dangerous, more like.
* Why are we not placing a DNA/Seed-vault on the moon
* Why are we not depositing resources on the moon
* Why dont we plan, plant, place autonomous robotic pods on the moon that can be called down/up carrying various resources
* what happens to the moon if we transfer water/create water on the moon
* Why cant this be a global effort, in the sense that we are talking about colonizing/visiting mars, but we can't even colonize the moon? What/Who is blocking this effort?
* Why aren't we actually practicing mars colonization on the moon first???
---
There are so many questions that I have about moon colonization/exploration that are so flippantly replied to as cost...
It feeds my tinfoil: there are things on the moon they dont want us to see??? (I know, just as flippant - but c'mon humanity, get your shit together and put some known colonies on the freaking moon!)
Because it's expensive to get it there, useless on the moon, and expensive to get it somewhere useful in the event of need, all because of gravity wells.
> Why are we not depositing resources on the moon
Same answer.
> Why dont we plan, plant, place autonomous robotic pods on the moon that can be called down/up carrying various resources
And, again, same answer, both for the pods and the resources themselves.
> what happens to the moon if we transfer water/create water on the moon
It boils off and leaves, possibly after freezing for a while, depending on the time of lunar day you deposit the water, IIRC.
> Why cant this be a global effort
Because a really bad idea doesn't get better because more people are involved.
> Why aren't we actually practicing mars colonization on the moon first?
Because the Moon isn't very much like Mars in ways relevant to colonization, so there is no value to doing that. While perhaps some relevant technologies might benefit from the shorter feedback cycles of Earth-Moon missions for refinement, the costs of such missions are close enough to Earth-Mars missions that it's generally not worth it to go to the Moon if your goal is Mars. Just go to Mars.
Can you imagine if all of a sudden, out of the ground a bunch of Dinosaur scientists emerged having kept themselves in cryo-suspension with all of their dinosaur tech to reestablish themselves as the dominant species on the planet? Are they going to be conflicted? Do they just eradicate humans because they were first? I'm sure Charlie Stross could make up a good story along those lines. I'd read it for sure :-)
But the meta question, the big one behind all those "Why"s up there, is well understood. As a planet, and certainly as a nation, and even on as small a scale as a city, we are divided in our understanding of the reasoning for why being a multiplanet species might be more important than say, feeding the starving in Sudan.
You can have a room of 100,000 people shouting in unison to colonize Mars and that is an insignificant fraction of the people who would have to be aligned to make that the generally agreed upon plan.
And that is one of the things that makes this announcement so amazing to me. When we achieve that moment where a small enough group of individuals can effect a legitimate colonization effort, then it can happen without consensus of a nation-state and can proceed based on the self interest of a much smaller group. And while it is a staple in science fiction that corporations have fleets of space craft they use to achieve their interplanetary goals like an inter-solar Dutch East India company, I never expected it to be possible for a company to be able to do that in my lifetime.
Also a private entity can't assert jurisdiction over anything, you have to be a state to do just that.
[1] https://www.bloomberg.com/news/articles/2017-02-27/tesla-slu...
Downvotes? Ah, i forgot that around here one is not supposed to question anything that Elon does.
Some things to consider, China has been working up to getting a space capability to send people to the Moon with the full backing of the government funding, by 2035[1]. They started in 2003. SpaceX was founded in 2002 and they are saying they will fly someone around the moon next year? Dragon has the deltaV to land on the moon (not sure if it has enough to get off again though) and SpaceX certainly has the expertise in building spacecraft that land.
The next person to take a picture of the Earth from moon may not be on a government funded mission. That one really blows my mind. For so long it was only countries that could do something like that, now it is nearly within reach of individuals.
The UN has treaties about claiming (or not) the moon by a nation state, but there isn't anything about a privately funded and established outpost that wants to declare independence. All this time I imagined that some country would establish a base there, and grudgingly offer up some space for non-state use, and now there is this possibility of a private facility that states have to ask permission to visit? That is priceless.
[1] http://blogs.wsj.com/chinarealtime/2016/04/29/man-on-the-moo...