Space - The Final Frontier

[Peter]

Quote:

Originally Posted by 6miths The achievements of that era were astounding and sometimes leave me feeling a bit saddened when reflecting on what we have done since.

+1

[growing_older]

Quote:

Originally Posted by 6miths The achievements of that era were astounding and sometimes leave me feeling a bit saddened when reflecting on what we have done since.

Also amazing is the timescale used. One significant milestone after another, often with mere months between major launches or upgrades. In my work, we sometimes plan months for a user interface update or a color change on a website. Shocking to consider the advances the Apollo engineers were making and how quickly they were doing it.

[Chuckanut]

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Originally Posted by growing_older Also amazing is the timescale used. One significant milestone after another, often with mere months between major launches or upgrades.

FYI, the next Orion launch is scheduled for 2018. The first manned launch is scheduled for the early 2020's.

In the 60's we went from never having put a human into space to the first man on the moon in a little less than nine years.

[clifp]

Quote:

Originally Posted by Chuckanut FYI, the next Orion launch is scheduled for 2018. The first manned launch is scheduled for the early 2020's. In the 60's we went from never having put a human into space to the first man on the moon in a little less than nine years.

I guess I should preface this snarky comment and article by saying anything in space is pretty cool in my book.

So I echo Elon's gracious tweet. Congratulations to @NASA on the flawless Orion flight, as well as to program prime contractors @LockheedMartin and @Boeing!

That said I totally agree with this Guardian article.
The headline says it all

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Orion: a last-ditch effort by a fading empire that will never strike back Joe Pappalardo

The rest of the article makes good points.

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If the new space race was like the movies, this week would be The Empire Strikes Back... And of course there’s that other curse haunting Orion: It won’t carry actual people until around 2022. And that’s if the budgets hold out. The incoming Congress may not shut down a program like Orion, but they can starve it of fuel until it enters a netherworld of delays, life-support funding and lethargy. When it flies on missions, it will be outdated. Orion is particularly vulnerable since, you know, Nasa has not set a destination for it to go. If the first manned test flight is in 2021, when will the actual mission to Mars be funded and staged? It takes a very optimistic person to think the funding and tech will be ready by 2022 – or even 2025. The Orion launch has been be a triumph of engineering, hiccups and delays aside. But the Empire may not love the sequel. SpaceX is planning a historic launch of its own next year – the rocket is called the Falcon Heavy. Yes, Musk named his rocket after the Millennium Falcon of Star Wars, and he promises it will take twice as much payload into space as the one Nasa launched on Friday, and at one-third the cost. So far his claims about SpaceX have come true, and soon he’ll be fighting, with the lobbyists and the politicians who play favorites, for satellite contracts worth hundreds of billions of dollars. Combine that kind of force with Elon Musk’s capsule full of actual people returning to space – under a Nasa contract to deliver astronauts to the International Space Station – and you have a private startup that can beat Nasa or any other government agency back to the moon, if it so chooses. Return of the Jedi, indeed.

[M Paquette]

If we had gone with the original Project Orion, we would have had a manned mission to Mars in 1965, and the first manned mission to Saturn by 1970.

The spacecraft proposed ranged in size from a modest 6,000 tons to the Saturn mission at 8,000,000 tons.

Alas, the project was cancelled.

https://www.youtube.com/watch?v=E3Lxx2VAYi8

[Chuckanut]

The things that companies like SpaceX are trying to do remind me of NASA in the 60's. Can you imagine being able to actually land a used booster rocket onto a platform in the ocean? And later on land? This was the stuff of science fiction when I was a kid.

[clifp]

Quote:

Originally Posted by M Paquette If we had gone with the original Project Orion, we would have had a manned mission to Mars in 1965, and the first manned mission to Saturn by 1970. The spacecraft proposed ranged in size from a modest 6,000 tons to the Saturn mission at 8,000,000 tons. Alas, the project was cancelled. https://www.youtube.com/watch?v=E3Lxx2VAYi8

That's some really cool stuff. I've heard about the nuclear powered spaceship before, but never really seen much in the way of detail.

Obviously Dyson is a genius physicist, but brilliant scientist aren't the most practical engineers. So since you are my resident nuclear engineering expert, would it have worked?

[M Paquette]

Quote:

Originally Posted by clifp That's some really cool stuff. I've heard about the nuclear powered spaceship before, but never really seen much in the way of detail. Obviously Dyson is a genius physicist, but brilliant scientist aren't the most practical engineers. So since you are my resident nuclear engineering expert, would it have worked?

The physics are absurdly simple. There is a massive pusher plate, a humongous shock absorber, and the payload. Small atomic bombs are set off below the pusher plate. The impulse from detonation acts on the pusher plate just like the combustion in a rocket acts on the combustion chamber. The shock absorber and pusher plate mass act to smooth out the acceleration seen by the payload.

Of course, you don't want to be near the launch pad...

Some early variations ground launched using specially engineered, very 'clean' nuclear explosives. Without the requirements of weapons systems, materials could be selected to minimize induced radioactivity and fallout from the first several blasts to get clear of the atmosphere. Other variations launched from orbit, removing this problem.

Note that 'atomic blasts in spaaaace!' aren't much of a radiation hazard compared to the radiation from the 100,000,000,000 one megaton H bombs per second going off in the center of the solar system. Good thing our little planet comes with radiation shielding, huh?

[Lakewood90712]

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Originally Posted by Chuckanut FYI, the next Orion launch is scheduled for 2018. The first manned launch is scheduled for the early 2020's. In the 60's we went from never having put a human into space to the first man on the moon in a little less than nine years.

Great to see the test went well. A little disappointed in the time frame too. But the 1960's was all about beating the Russians , not smart use of resources.

[clifp]

Quote:

Originally Posted by M Paquette The physics are absurdly simple. There is a massive pusher plate, a humongous shock absorber, and the payload. Small atomic bombs are set off below the pusher plate. The impulse from detonation acts on the pusher plate just like the combustion in a rocket acts on the combustion chamber. The shock absorber and pusher plate mass act to smooth out the acceleration seen by the payload. Of course, you don't want to be near the launch pad... Some early variations ground launched using specially engineered, very 'clean' nuclear explosives. Without the requirements of weapons systems, materials could be selected to minimize induced radioactivity and fallout from the first several blasts to get clear of the atmosphere. Other variations launched from orbit, removing this problem. Note that 'atomic blasts in spaaaace!' aren't much of a radiation hazard compared to the radiation from the 100,000,000,000 one megaton H bombs per second going off in the center of the solar system. Good thing our little planet comes with radiation shielding, huh?

Very interesting. But how do you build a pusher plate that can survive being on the close proximity of scores or hundred of small atomic bombs. If read some the documentation correctly they were looking at small A bombs have the equivalent explosive power of hundreds tons of TNT.

Our largest conventional bombs have been 10 tons and they can cause damage to bunkers, dams and other harden targets.

[Chuckanut]

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Originally Posted by Lakewood90712 But the 1960's was all about beating the Russians , not smart use of resources.

Good point. IMHO, the #1 reason to develop an ability to work in deeper space is to detect objects that might crash into Earth and divert them. That is a lot easier to do when they are still many millions of miles away.

[M Paquette]

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Originally Posted by clifp Very interesting. But how do you build a pusher plate that can survive being on the close proximity of scores or hundred of small atomic bombs. If read some the documentation correctly they were looking at small A bombs have the equivalent explosive power of hundreds tons of TNT. Our largest conventional bombs have been 10 tons and they can cause damage to bunkers, dams and other harden targets.

Two 'tricks' here. First, these nuclear explosives are designed for propulsion, not breaking structures apart. They'll probably use a disk-shaped reaction mass that will collimate the plasma from the blast into a 'cigar' shape to improve the overall coupling to the pusher plate. The pusher plate will be specially shaped and quite large, roughly similar to the diameter of the nuclear fireball created by the explosive, and a bit more than the radius of the fireball away from the detonation point. The concave shape of the plate will receive the force of the blast fairly evenly across it's surface. An ablative material would coat the pusher plate to take the heat damage from the plasma impact. One design proposed using a graphite-oil mixture to be strayed between detonations.

There won't be the large difference in force over a surface that contributes to stress failure, or the force from directions the structure is not designed for that brings down dams or buildings.

Much of the mass of each 'bomb' is reaction mass for the Orion, not nuclear explosive. The small 5 kT charges for the 4,000 ton Orion would have a mass of about 1.2 tons. That mass is converted to plasma by the nuclear charge, and becomes the reaction mass that strikes the pusher plate. The 8,000,000 ton 'Super Orion' would use larger charges, carrying a reaction mass of 3,000 tons that would act on a pusher plate with a diameter of 400 meters.

At the end of the project, Freeman Dyson sketched out a starship design that would carry a city of 20,000 people to Alpha Centauri over the course of many generations. I understand that this is the design the creators of the SyFy miniseries 'Ascension' went with for their generation ship.

[M Paquette]

Even without "Old Bang-Bang", we had some other interesting unconventional rockets available for a Mars mission.

The Nuclear Engine for Rocket Vehicle Application (NERVA) project actually built, tested, and in 1968 certified an engine design for a manned Mars mission planned for 1978. NERVA powered 'tugs' would haul equipment from low earth orbit (LEO) to space stations and a permanent lunar base then scheduled for 1981. The NERVA would also act as an upper stage (Saturn S-N) as part of the Saturn C-5 to carry payloads of up to 170 tons to LEO.

The test rockets were run out at Jackass Flats, Nevada. The darn things would run for hours at a time, with twice the specific impulse of chemical rockets (better reaction mass efficiency, or less propellant for a given end velocity).

The NERVA enabled a Mars mission, and that was their undoing. Congress could see the end of the line with the Apollo 11 moon landing, and commitment for a Mars landing implied decades more funding for the space program at levels similar to the moon landing commitment. The nuclear rocket enabled the Mars mission, therefor killing the nuclear rocket made the Mars mission impractical, and the space program funding could be cut back.

https://www.youtube.com/watch?v=j6gKFvPjGpQ

[Free To Canoe]

JPL | News | How NASA Curiosity Instrument Made First Detection of Organic Matter on Mars


News on organic molecules found on Mars.


The only aromatic hydrocarbon found was chlorobenzene. Concentration levels are estimated to be in the low ppb range. It's not like the planet is choc full of em.


Interesting how they needed to explain what an organic molecule is in the first paragraph and climate conditions on Mars in the second one. NASA dummying down on us?

[clifp]

Elon Musk is doing Space X focused AMA on reddit right now.

Here is the link if you want to ask questions.

[REWahoo]

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Originally Posted by clifp Here is the link if you want to ask questions.

Has anyone asked him if he knows the definition of insanity?

Elon Musk Divorces His Wife Talulah Riley - Again

[clifp]

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Originally Posted by REWahoo Has anyone asked him if he knows the definition of insanity? Elon Musk Divorces His Wife Talulah Riley - Again

LOL not yet but I still have 1300 comments to read. Actually it is really a cool AMA, hundreds of high school and college age kids telling how he has inspired them and asking for his advice on how to change the world.

[ChadR]

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Originally Posted by clifp Elon Musk is doing Space X focused AMA on reddit right now. Here is the link if you want to ask questions.

That was cool!!

[clifp]

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Originally Posted by ChadR That was cool!!

The way beyond cool thing is trying to land the first stage of Falcon 9 on a barge in the middle of the ocean. It is huge step in trying to reduce the cost of delivering payloads to space by 99%..

Even for a person from the semiconductor industry where we managed to achieve 99% cost reductions every 15 to 20 year (i.e. Moore's Law) or so it is still an audacious goal.

[Chuckanut]

Another successful launch for SpaceX. I am sure NASA must be relieved after the unfortunate disaster that was the previous supply launch by Orbital Sciences.

The barge landing was a partial success, if I understand correctly what happened. Apparently the first stage made it to the barge, but hit it to hard damaging the barge and the rocket.