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NASA Announces Design for New Deep Space Exploration System

nasa.gov

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Re: NASA Announces Design for New Deep Space Exploration System

#51

Post by [deleted] »

Udo wrote: post #29
timroman wrote: post #9

Earlier quoted context omitted.

I think the problem is that the things NASA wants to send into orbit are much larger than what the commercial space industry is planning to send into orbit. That's why NASA is taking the lead and building a vehicle specifically designed for large loads rather than people or satellites.

I disagree. Commercial launch systems are just beginning to unfold and for example SpaceX has already announced plans for heavy lift versions in the very near future. Contrast this with the SLS, which is the umpteenth attempt at rediscovering how the mysterious and ancient Saturn V worked, and which will probably be cancelled within three years without ever producing something that can actually get off the launch pad…

[deleted]

Re: NASA Announces Design for New Deep Space Exploration System

#52

Post by lucasjung »

nknight wrote: post #49

I have a sophisticated layman's understanding of stuff like orbital mechanics, launch energies, etc., but one thing I've never been entirely sure of: Why are rockets always round? I'm guessing it's the least-questions-asked shape as far as aerodynamics goes, and gives good weight efficiency assuming you can build what you need into a round shape. Is there anything more fundamental than that?

I would guess that it's a whole lot of reasons including the reasons you stated. I would also add a couple (and there's probably more):

Round is structurally strong (which, when it comes to aerospace engineering, is really just the opposite side of the "light weight" coin).

Symmetry of shape and mass makes the stability and control equations a hell of a lot simpler to deal with, and a round shape makes it easier to be (nearly) symmetrical in more ways than with other shapes..

Re: NASA Announces Design for New Deep Space Exploration System

#53

Post by gregatragenet »

nknight wrote: post #49

I have a sophisticated layman's understanding of stuff like orbital mechanics, launch energies, etc., but one thing I've never been entirely sure of: Why are rockets always round? I'm guessing it's the least-questions-asked shape as far as aerodynamics goes, and gives good weight efficiency assuming you can build what you need into a round shape. Is there anything more fundamental than that?

A rocket is a series of pressure vessels, pressurized fuel tanks, pressurized crew compartment, etc.. Round shapes spread the pressure around the entire structure. The ideal shape for pressurized vessel is spherical, however for aerodynamic reasons cylinders with rounded ends are used.

Re: NASA Announces Design for New Deep Space Exploration System

#54

Post by VladRussian »

EREFUNDO wrote: post #42

The Chinese explored the Middle East and Africa almost 100 years before the Europeans. Every expedition consisted of 300 ships, some as long as 400 feet with 9 mast and an armada crew totaling 28,000 men. After 30 years of doing it they realized that they were spending too much money on these grand expeditions. The succeeding emperor ended the program. The Europeans on the other hand would send out just a few ships a…

it can be turned the other way as well - Chinese fell into stagnation and lost the technological, power and all other races during last 2-3 centuries because they stopped the exploration and closeted themselves inside their kingdom.

>We stopped the moon landings for the same reason the Chinese stopped landing Eunuchs in Africa.

and we don't go to Mars and beyond for the same reason Chinese didn't venture deep into and across the Pacific to America - too technically challenging, unknown and dangerous

Re: NASA Announces Design for New Deep Space Exploration System

#55

Post by HeyLaughingBoy »

sliverstorm wrote: post #33
zzzeek wrote: post #31

About six paragraphs that need to mention "cost" or "jobs created", only one at the bottom that has some actual scientific goals. How far we've fallen

It's a symptom of the times. People don't care about science today, they care about jobs, and NASA is trying to play that tune to keep themselves afloat.

When have people never cared about jobs? When have they (outside a select few) ever really cared about Science?

Re: NASA Announces Design for New Deep Space Exploration System

#56

Post by HeyLaughingBoy »

nknight wrote: post #49

I have a sophisticated layman's understanding of stuff like orbital mechanics, launch energies, etc., but one thing I've never been entirely sure of: Why are rockets always round? I'm guessing it's the least-questions-asked shape as far as aerodynamics goes, and gives good weight efficiency assuming you can build what you need into a round shape. Is there anything more fundamental than that?

My educated guess: it's because a cylinder is the easiest shape to form sheet metal into. It also avoids multiple seams which are failure points. As a side effect, the stress concentrations at sharp corners are avoided.

Re: NASA Announces Design for New Deep Space Exploration System

#57

Post by russell »

derrida wrote: post #23
russell wrote: post #18

"...kids today can now dream of one day walking on Mars." Hell, I dreamed of walking on Mars when I worked on the Apollo Project. I never dreamed that 2011 would come and we would never have even gone back to the moon. It makes me regret even more that I never made the trek to Florida to see a Saturn V launch.

You worked on the Apollo Project!!! What was your role in the Apollo Project?

I worked at the MIT Instrumentation Lab on a compiler for the Apollo Guidance computer. The language was rather bizarre. Each line was encoded on 3 punched cards. One for the main expression, one for subscripts, and one for superscripts. I was pretty junior so my task was really at the front end processing compiler options and reading the input.

The Lab was a really interesting place. Lots of high end 360's, which couldnt even power a phone these days. We had our own command module mockup, but I was an employee of a contractor, so no-one would let me play around on the inside, but I did get to peek.

In the grand scheme of things, my role was miniscule, but I am still very proud that I was able to contribute to one of the greatest adventures of the last century.

Re: NASA Announces Design for New Deep Space Exploration System

#58

Post by rbanffy »

mchusma wrote: post #46

Nice to see that the most common reaction to this article, even among space geeks, is that this is a waste of NASA's focus and everyones tax dollars. I think that bodes well for progress.

> the most common reaction to this article, even among space geeks

As Richard Feynman once said, "For a successful technology, reality must take precedence over public relations, for nature cannot be fooled".

Re: NASA Announces Design for New Deep Space Exploration System

#60

Post by Jeng »

RexRollman wrote: post #17

Don't get me wrong, I am pro space exploration and love science, but I just don't see how we can justify spending money on this kind of project with the economy as it is.

If factories get shut down and re-purposed it costs a lot more to then create new factories if you need to build that product again at a later date.

Long term wise how can we justify not spending money knowing that we will spend less in the long run if we spend big in the short term?

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