Simon Ross

In layman terms, a man rated booster has to match some very stringent NASA requirements in terms of safety, escape systems, vibration tolerance and max G imposed during the ascent and return phases of a flight. Basically inert cargo doesn't really care if a booster subjects it to 10g during an ascent, human beings on the other hand tend to black out or die. The two key areas are safety and max G, any man rated system now requires a system to physically get the crew away from an in flight incident and to keep any g forces during ascent below 3g . To do this requires a lot of extra hardware (weight) and the ability to either de tune the engines used or run them below their optimum thrust profile. Basically, man rate a booster that is designed to lift cargo to orbit is pretty much like making Usain Bolt run 100 metres with one arm tied behind his back, yes he can still do it, but trust me, he isn't going to get close to running it competitively.

Sounds like a good reason to pull the plug on Orion and go with the commercial crew vehicles under development. Quite frankly, Orion simply has no real purpose any more. It was specified as part of a programme that has been cancelled and for missions that no longer exist. This is the whole problem with man rating SLS to carry Orion, the moment you do the cost goes through the roof, the performance and payload fraction go through the floor. It's almost as if every lesson we have learnt from both the Saturn 5 and Shuttle programmes have been totally forgotten.

Well certainly both the Delta 4 and Atlas 5 are currently being evaluated as possible manned boosters, it would certainly make a lot more sense then trying to man rate the SLS. Trying to man rate a HLV is just plain daft, you end up with the same technology roadblock that killed off the Saturn 5.

I think at that stage you might as well shut the manned mission section of NASA down and just give the budget directly to the Russians ! There simply wont be any future interplanetary manned missions. Personally I think the SLS is a bloody terrible idea, but it does happen to be the only chance NASA has to stay in the manned space flight business.

And as I have already agreed, an impressively long list of scientific experiments. Really doesn't answer the basic issue, what's the point of all of it if you haven't really worked out the basics of getting crew and materials to LEO and beyond in any form of economical way ? I'm not anti ISS, I am simply very anti how it was actually realised. 100 billion dollars could have done a hell of a lot more in terms of developing launch capability, true HLV's, advanced nuclear engines etc... Instead it has been sucked up by the ISS and we are no more capable in terms of launch capability then we were 40 years ago ( in reality, we are actually less capable now).

The history of the Shuttle is certainly complex. None of the original proponents ever envisioned it to be a one size fits all vehicle, just a cheap way of getting a crew into orbit with a small payload (< 5 tons) for scientific study. Unfortunately, the only way Shuttle would get built eventually was to meet the USAF requirement for a vehicle capable of orbiting their proposed 'Big Bird' satellite which required a 25 ton payload capacity and also they added a massive increase to the cross range capacity resulting in the heavy delta wings of the final design. There isn't actually anything wrong with the idea of a reusable space shuttle, you just need to design it for the purpose it is best for, get a crew to orbit safely, get it back safely and enable a quick turnaround. which doesn't require weeks of refurbishment to the craft. What NASA actually did with the Shuttle is remarkable, they met all the requirements forced upon them at the time, and is still to this day one of the most remarkable engineering achievements ever built. The basic problem is it is just about the worst way of lifting materials into orbit ever built. So fast forward to 2013, Constellation is dead, we now have the SLS, again NASA forced by budget restrictions to combine the functions of a HLV into the functions of a man rated vehicle. We don't really seem to have learnt a damn thing:-(

Quite simply because trying to compare exploration missions like Cassini to the ISS is like trying to compare apples with oranges. In addition, missions such as Cassini, Curiosity etc.. are funded at a tiny fraction of the assembly and ongoing operational costs of the ISS. It may seem that I am anti ISS, but lets take a cold, hard rational look at what has been achieved by it and ask the fundamental question - Has all the time, effort and money invested in the ISS enabled us to enhance our capability to reach Leo and beyond ? The cold, hard answer is NO ! 40 years ago, Nasa was an organisation that was capable of launching a manned, heavy lift space craft to another planet, now that same organisation cannot launch a single man to orbit with it's own hardware ! Perhaps it is my warped perspective living on the other side of the Atlantic, but it seems to me fundamentally wrong that the richest, most powerful nation in the world can have a massive space station sitting in orbit, yet no longer has the capacity to reach it on it's own. 100 billion dollars, think about that figure, mull it over in your mind, it's a huge amount of money. What else could have been done with that kind of funding ? What opportunities have been missed ? Here is just one... Develop a true heavy lift vehicle. OK. so you want to place a large space station in orbit, unfortunately all you have is the limited payload the shuttle offers so it has to go up in 25 ton sections increasing both the cost, technical complexity and the number of interfaces required on the station. So someone has the bright idea to revisit some of the post Apollo heavy lift proposals to see if there is a better way to do it (this of course never happened, Nasa were still in denial that their elegant, high tech spaceplane was the single worst economic way of getting large amounts of material into orbit ever built) If they had done, they would have found many different proposals, but many of them shared the basic concept of KISS, separate out heavy lift duties and keep the design as simple as possible.. One typical proposal was Sea Dragon, a monster 2 stage launch vehicle that took the concept of the Big Dumb Booster and evolved it into a Very Big, Very Dumb Booster. Basically built in a standard shipyard out of standard 8mm steel using bog standard shipyard construction methods it's eventually towed out to sea, filled with hydrogen and oxygen and someone lights the blue touch paper. Whilst Sea Dragon was a beast of a launcher, it was also costed (and verified by independent bodies) as requiring a fraction of the development and construction cost of the existing Saturn 5 launch system. It's construction was simple, it's engines were simple, it contained just about enough technology to put itself into the orbit you wanted and most important of all, it wasn't man rated, it never would be. So lets go a little further down this road. From 1964 until 1973, a total of $6.5 billion ($46.77 billion present day) was appropriated for the Saturn V development and construction of the flight articles. Estimates for the development and first 5 flight articles of Sea Dragon were thought to be in the region of 25% to 35% of the Saturn V programme costs. Well, we all know that major construction projects over run, so lets pick a more realistic figure of 50% of the Saturn V cost. so what do we get for our $23 billion Well the first thing you get is a launch system that can place 550 tons into Leo. Think about that figure, that's an entire ISS sized space station placed into orbit on a single launch ! Better still it wouldn't be the complex, modular, cramped (and very expensive) station we have today, but would be much more along the lines of a giant sized Skylab, much more interior space, far fewer interfaces to go wrong and best of all, a fraction of the cost of trying to launch the ISS one piece at a time. Quite simply, the cost savings on the station alone would have more then paid for any possible over run on the Sea Dragon development. And now comes the even better bit, for our $23 billion we still have 4 flight articles remaining capable of putting 2200 tons total into LEO. That's a moon base, or a manned Mars capable landing system or simply more giant Skylab type modules to our already large station. Hell, why settle for 3 people up there when we can comfortably house 30 ? A flight of fancy ? Not really, the Sea Dragon concept and technology was well understood even in the 60's, you really don't need a lot of technology to get large masses into orbit, you simply need a lot of grunt And this is what basically frustrates me with the ISS, we could have done it differently, at lower overall cost, built a better station and developed a true heavy lift capability that would have effectively opened the solar system up for manned flight. But we didn't, did we.

With respect, I take a great interest in what the ISS is used for. Yes, it's an impressively long list of experiments. However.... After 15 years and 100 billion dollars could you please point me to the experiments where 1) It has a direct impact on our ability to explore space safer, cheaper and faster 2) It has a direct impact on our ability to manufacture materials / processes that can be replicated or up scaled to economical levels. 3) It has a direct impact on our ability to better understand our planet Again, I reiterate that the ISS has been a massive missed opportunity. The chance has been there for 15 years to actually solve many of the engineering issues that need to be addressed if we are ever to get out of LEO again. This has never happened and frankly now it never will.

In what way crucial to the future of manned space exploration ? Quite frankly, I just don't see it Operationally it's been up for 15 years, cost in excess of 100 billion dollars and really hasn't told us anything we didn't already know. Don't get me wrong, in the day I was fully supportive of the original concept, but that original concept and it's capabilities has long since disappeared. After 15 years, we still are no closer to developing a closed circuit life support system, and without that, we are going nowhere After 15 years we are still no closer to developing a centripetal force gravity system, and without that, we are going nowhere What we have learned is how to assemble large structures in orbit, but frankly we didn't need to spend 100 billion dollars to learn that

I hate to say it, but save both and cut back operations to the white elephant that is the ISS ! NASA is at it's absolute best when it is conducting deep space research and rover based missions, the amount of bangs it produces for the bucks it spends is truly astounding. In terms of manned space flight, NASA has been the exact opposite for a number of decades, firstly with the horrendously expensive and dangerous shuttle, then with the ISS, a bus stop on the road to nowhere.

Rather like the SLS, what would you actually use a 130 ton launcher for ? Having the capability is great, but with no manned moon or Mars missions planned it is massively overpowered. Only possible mission I can envisage getting a green light needing that kind of payload capability would be a future Mars sample return probe

I'm of the opposite view of most of the people posting it would seem. While I am fairly sure the universe is full of life bearing planets, I suspect intelligent life may be a bit of a fluke. From our own experiences of the earth, we know life started pretty early and managed to survive some pretty traumatic events including near extinction events. All in all, it would appear that life is pretty tough and will survive in most environments and through most disasters. Intelligence on the other hand seems to have occurred only once (that we know of) and seemed to take a very long time to develop given that mammals have been around for the best part of 250 million years. Also puzzling is the fact that the development of intelligence completely bypassed entire groups of animals that occupied the earth for far longer yet must have had the same environmental and biological pressures on them to develop a more efficient method of survival. I suppose the jury is out on whether intelligence is actually an efficient long term survival trait. As others have already mentioned, intelligence could place such a heavy demand on the resources available to it on the planet of it's birth that it ends up simply running out of basic materials and power sources before it can develop the technology to seek them further afield. In which case, yes there may well be other civilizations out there, but there is a good chance that they are living in a post technology dark age, one from which there is no possibility of escape

It really depends on what you define as a heat shield. On most traditional capsule type re-entry vehicles it has been an ablative type heat shield. On the Shuttle it was ceramic charring heat shield. In reality, there are a number of metals you can use as a heat shield, all of which will dissipate heat faster then they will absorb it during re-entry and are re-usable. Only problem is, most of them are very heavy.

Sorry, no older patches, 0.22 only Loving some of the shots I have seen so far, but come on guys, no mechjeb, still waiting for one of you to post our first genuine height record

LOL GM. Kerbal survival is an optional extra :-)

OK, a very simple, but hopefully fun challenge for everyone out there. Not sure if it has been suggested before, but couldn't find it with the forum search facility, so here goes.... The challenge is very simple, to see who can gain the highest altitude using nothing other then mono propellent tanks and RCS thrusters. The Rules You may use any stock items you like, however any thrust must only come from RCS thrusters You must have at least one Kerbal aboard No mods are allowed, this includes MechJeb and Flight Engineer All submissions must include an image of the finished ship in the VAB, in flight and in the final flight stats image Other then that....Have fun :-)

I do not believe that labelling a fellow thread poster a 'sociopath' is either helpful or desired when having a debate. You may or may not agree with the poster's opinion, but counter it with intelligent debate and not insults.

In truth, I cannot see what is remotely dubious about the conclusion of the article. We know from scientific observations that planetary systems exist around many stars, and through the process that those systems are formed by, it is inevitable that a percentage of 'earth like' planets are going to form within an orbit that will allow liquid water to exist on the planet's surface. However !!! An earth like planet, is not the same as a life bearing planet. An easy example is Venus, very much an earth like planet in terms of size and composition and according to certain models, actually sits on the edge of our 'Goldilocks' zone, yet no one is expecting to find life there.

Much as I would love to think that we as a species will evolve to the point of losing our aggressive streak, I somehow don't see it happening. I suspect that the very first questions that will be asked during any encounter with alien life will be the following... Is it a danger to us ? How do we kill it ? Can we eat it ? Can we exploit it ? I would like to think I am wrong, but somehow I think that is pretty much the way it will go

A condom. Possibly the least form of protection I will need

No, alien life forms must be protected at all costs !!! After all, we are going to need something to deep fry when we get there :-)

Thanks Greg, was getting a bit frustrated as to how to get the images displayed :-)

Grrrr, gonna try that again :-)

Had a lot of fun with this one :-) For the record managed to achieve 740943, didn't quite make orbit but working on it. The beast in the VAB The beast in flight And finally, the beast at it's high point

Got to be Eve Managed flybys, probe landings but never managed to do a manned return using stock parts, the planet simply eats Kerbals for breakfast ! Currently working on a 3 launch mission, so will see how it goes this time :-)