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SpaceX Discussion Thread

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Also, spot the difference: (before and after)

lE8cifG.jpg

ENzsosw.jpg

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Posted (edited)
22 hours ago, cubinator said:

I did catch the sarcasm. It sounds like Mars entry would be around 4-6 g normally, but still, that counter was over 10 and it would likely be much more at a higher entry speed, so it's still potential for at least unconsciousness (spinning backwards for a red-out?) which is not something you want when about to land in a spaceship.

The flight and landing is fully automated- so it really doesn't matter when in the flight you fall unconscious.

 

And, for the record, peak g-forces are usually *higher* in stock KSP.  Earth has a MUCH larger scale height (5.6 vs 8 km) for its atmosphere than Kerbin, which means you have more vertical distance to bleed off a given amount of speed.  I'm not sure at what point in the flight you're saying your ship would experience 10 g's (if it's during the flip- the real maneuver would be performed at much lower g's than anything possible in KSP), but if it's it the landing-burn, by which point all a spacecraft has left after re-entry is vertical (downwards) momentum, you'd actually be moving *slower*, at closer to terminal velocity on Earth, due to the planet's larger scale height...

Edited by Northstar1989

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13 hours ago, Green Baron said:

Edit: experience shows that if a complex project gets shifted forward too often then it'll never be finished. That may be because funds running out, technology not ready, risks incalculable or dwindling overall support. Or a combination thereof.

You're mixing up cause and effect (correlation does not equal causation- at least not in the direction one assumes).  It's the set of problems such as inadequate funding and support that lead to delays, and the delays are only used as a proximate excuse to cancel a project that politicians and wealthy donors/investors were never willing to fund adequately in the first place, often when it really was possible all along.  It's not the delays that lead to problems, but the problems that lead to delays.

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13 hours ago, Green Baron said:

I don't think it is fraud. Just ... overenthusiastic.

It is absolutely ok if a guy like Musk, Branson and the many other utter their dreams and ideas even if they are beyond current capabilities. One just shouldn't run after every guru who promises a new world. Wait until they show up with a realistic plan, best a technology demonstrator, and others jump the train to develop all that is necessary.

Edit (once again): look, they have made that marvellous F9 rocket, so the basic capabilities are there. It is just that technology cannot be scaled indefinitely without sideeffects, in this case vibration, aerodynamics, and so on. Every material has its limits.

If everyone adopted that philosophy (let someone else jump on the train first), nothing would ever get accomplished.  You have to dare bravely, and sometimes fail miserably, to ever succeed amazingly.  Put another way, you miss 100% if the shots you don't take.

There ARE no physical reasons a rocket can't be built this large (the Saturn V was actually both taller AND wider than the current BFR design, with only a slightly smaller payload).  There are only political and possibly economic reasons holding us back.  You're saying something can't be done that waa already accomplished BEFORE, in the Apollo Program.  I can only imagine what you'd be saying if they stick with the original ITS design, which was *slightly* larger than the Saturn V instead of slightly smaller...

2 minutes ago, tater said:

Mars is not habitable. Built environments on Mars are habitable, and pressure tight, built environments could be placed anywhere and be habitable. Mars has almost nothing going for it. 

Built habitats require mineral inputs to maintain.  Recycling is not to the point yet where we can survive without constant metal inputs.  Mars has plenty of metals to sustain a built habitat, desert islands do not (and, as I just explained, would not be long-term survivable even WITHOUT a built habitat.  No metals means no agriculture or fishing ships on a desert island, which means eventual starvation...)

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Posted (edited)
12 hours ago, sevenperforce said:

Solution: Put an ISRU rig a few dozen meters away from the runway with a Klaw sticking out of one side. Build your plane with bingo fuel, roll over and jam yourself into the Klaw, then fuel up.

Seems cheat-y to me.  Besides, my rig already chokes on lag with relatively small, low part-count rockets.  Adding an ISRU rig to the picture (and probably a refueling rover- since refueling reusable rickets that way is impossible, and taxiing spaceplanes is a pain) would probably cause it to melt...

4 minutes ago, tater said:

The desert island people might be able to build boats, they don't need metal, they used wood.

Clearly, you don't know much about ship-building.  Large ships (the kind that are capable of crossing the Atlantic, and not just short, risky voyages between Polynesian islands) REQUIRE metal to build.  You simply can't hold a large ship together without lots of metal nails, at a minimum...

4 hours ago, sh1pman said:

Elon selling houses on Jupiter with solar power. Obvious fraud! Everybody knows that Jupiter is too far from the Sun to have any useful solar power generation potential! 

DNdS9UA.jpg

Everyone knows you can't land on Jupiter either.  Obviously it's a joke...

Edited by Northstar1989

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Posted (edited)
18 minutes ago, Northstar1989 said:

Everyone knows you can't land on Jupiter either.  Obviously it's a joke...

One day Musk will land a booster on Jupiter, I tell ya. And then reuse it. He's good at it.

Edited by sh1pman

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Hello, friendly neighborhood oppressor moderator here to remind all of you guys to try not to veer too far into politics. I realize that the nature of current SpaceX affairs tends to be intertwined with politics, but let's at least try to stay focussed. 

 

(Dont anger The Belters)

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3 hours ago, sh1pman said:

Also, spot the difference: (before and after)

lE8cifG.jpg

ENzsosw.jpg

I have no idea what those are but there are now three of them, falcon heavy confirmed?

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So, SpaceX, right? How bout that SpaceX.  :cool: Falcons & Merlins and great big rockets, oh my! Y’know, SpaceX... doing that SpaceX stuff... think there’s some stuff coming up pretty soon, right? *winkwinknudgenudge*

If only Elon Musk could harness the tangential energy of this thread, he could put the city of Miami on Pluto. 

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Posted (edited)
19 minutes ago, CatastrophicFailure said:

So, SpaceX, right? How bout that SpaceX.  :cool: Falcons & Merlins and great big rockets, oh my! Y’know, SpaceX... doing that SpaceX stuff... think there’s some stuff coming up pretty soon, right?

As we can see, any discussion about a way inevitably comes to the question of purpose.
Just face it...

P.S.
The same with the threads about SLS, Orion, etc.

Edited by kerbiloid

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6 hours ago, insert_name said:

I have no idea what those are but there are now three of them, falcon heavy confirmed?

Two launch clamps were added for FH side boosters

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I would be realy happy if we could keep the economical aspects of a mars colony in a seperate theard, afaik we allready had one. Those huge walls of text make keeping up with the thread realy hard while being only remotly about SpaceX...

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So is the Falcon Heavy launch go for November? Has it been Delayed again? 

I waited like 2 years for this fireworks show to happend, im getting a little impatient.

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58 minutes ago, NSEP said:

So is the Falcon Heavy launch go for November? Has it been Delayed again? 

I waited like 2 years for this fireworks show to happend, im getting a little impatient.

No more delays so far. Currently, the launch is scheduled for November.

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12 minutes ago, sh1pman said:

No more delays so far. Currently, the launch is scheduled for November.

Crossing my fingers!

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Posted (edited)

I posted the static fire, but it got buried. Thanks for keeping your eye on the ball, @Serpens Solidus!

I've suggested (as @Nibb31 just did) starting a space colonization thread. I started one a few times, but didn't have a lot to say for the OP, so I didn't bother. That might be a good place for some of this. There is clearly some SpaceX overlap with Mars in particular, but it goes into the science fiction weeds pretty quickly.

We should all take a break on one of the many islands that people managed to settle not only without metal, but without metallurgy as a set of knowledge... wish I was there right now (maybe it's time to think about a trip to Kauai).

Edited by tater

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10 minutes ago, tater said:

take a break on one of the many islands that people managed to settle not only without metal, but without metallurgy as a set of knowledge

 

Done, sir.

La Palma. No metal, no metallurgy until the Spaniards arrived and killed everyone who didn't submit to ... oops, politics. Or religion. Whatever.

 

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Let's talk ISRU with BFR. Presumably, the plan is to have an ISRU unit of some kind on one or both of the 2022 cargo missions and use a crane to deliver it to the surface. What then? Does it start scraping up dirt and using heat to try and release water from the soil? Drill for ice? 

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The ISRU is a major hurdle. Ice, as you say, might be somewhat akin to ISRU using lunar regolith, which is a major "earthmoving" operation.

Atmospheric would presumably be built-in to the vehicle, right? 

Power is another hurdle. They'd have to deploy massive solar arrays, or bring a nuke. The plus of this sort of cargo capacity is that the space nuclear power people could make something useful that would actually fit given the nice mass capability.

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13 minutes ago, sevenperforce said:

Let's talk ISRU with BFR. Presumably, the plan is to have an ISRU unit of some kind on one or both of the 2022 cargo missions and use a crane to deliver it to the surface. What then? Does it start scraping up dirt and using heat to try and release water from the soil? Drill for ice? 

Probably drill for ice, permafrost is probably common and you only need to heat part of the borehole to get liquid water you can pump up. 

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2 minutes ago, tater said:

The ISRU is a major hurdle. Ice, as you say, might be somewhat akin to ISRU using lunar regolith, which is a major "earthmoving" operation.

Atmospheric would presumably be built-in to the vehicle, right? 

Power is another hurdle. They'd have to deploy massive solar arrays, or bring a nuke. The plus of this sort of cargo capacity is that the space nuclear power people could make something useful that would actually fit given the nice mass capability.

IIRC, the Sabatier process requires both CO2 and H2O together, so the ISRU rig would have to be self-contained. If they were only cracking CO2 into LOX directly, they could use a self-contained solid-oxide system inside the ship, but that's not the case here.

The ship solar arrays might be enough to get it started, but I'm not sure.

4 minutes ago, magnemoe said:

Probably drill for ice, permafrost is probably common and you only need to heat part of the borehole to get liquid water you can pump up. 

Since you can't be assured of getting ice the first place you dig, you'll probably need a few separate (and, probably, independently autonomous) elements:

  • Drill/pump assembly
  • Atmospheric collection compressor
  • Power array
  • Synthesis unit
  • Refrigeration system
  • Storage tanks
  • Refueling robot

That's if you went with a drill.

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30 minutes ago, sevenperforce said:

Let's talk ISRU with BFR. Presumably, the plan is to have an ISRU unit of some kind on one or both of the 2022 cargo missions and use a crane to deliver it to the surface. What then? Does it start scraping up dirt and using heat to try and release water from the soil? Drill for ice? 

Why not start a new thread on this ? Let's try to keep the SpaceX thread clean.

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1 minute ago, Nibb31 said:

Why not start a new thread on this ? Let's try to keep the SpaceX thread clean.

I think it's relevant to the ongoing discussion of BFR. I wasn't saying "let's discuss ISRU generally".

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