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SpaceX Discussion Thread


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13 hours ago, TheEpicSquared said:

Some guy: "So, how fast did you run the marathon last week?"

You: "Let's see... that would be 0.00000000000000000000000000000000198% of the speed of light."

The guy: "0.0"

The guy: *backs away slowly*

That's really slow, I think.

c ~ 3x10^8 m/s

Cancel out 8 zeroes from your number

0.000000000000000000000000198 m/s

Let's split that up

0.000 000 000 000 000 000 000 000 198

A ten thousandth of a yoctometer every second. That's really slow.

Carry on.

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11 hours ago, cubinator said:

That's really slow, I think.

c ~ 3x10^8 m/s

Cancel out 8 zeroes from your number

0.000000000000000000000000198 m/s

Let's split that up

0.000 000 000 000 000 000 000 000 198

A ten thousandth of a yoctometer every second. That's really slow.

Carry on.

Reminds me of the XKCD "lethal dose of neutrinos from a superova"

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3 hours ago, magnemoe said:

Do not stay inside an star then it go supernova. 

I feel like you can just drop the rest of the sentence after "do not stay inside a star" and it's equally-good medical advice.

1 hour ago, tater said:

 

 

Looks like aluminum grid fins again. Surprising.

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Might as well use them up.

So I had this idea. F9 block 5 certainly gains some more payload margin to GTO, eating into any need for FH.

People talk about raptor US (which buys ~20s of Isp), which I don't think will happen. What if they use the US as a testbed for BFS refueling?

Put the BFS refueling gear on the back of F9 S2, and add some batteries, and/or solar to the payload mounting area. Make a "tanker" S2 where the payload is either nothing but some RCS, or another tank. Launch, rendezvous, and dock. Transfer props to the payload S2, deorbit tanker. They get to test, and maybe launch an otherwise just FH-sized payload to GEO of rt. cost of 2 upper stages, and propellant for 2 boosters.

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11 minutes ago, tater said:

Might as well use them up.

As I understand it, Al grid fins can be reused after LEO re-entries but get torched in GTO re-entries. So there's no reason to use the new titanium ones on LEO launches, but if they are used on GTO launches then they are expected to be expended. (The grid fins, not the stage).

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25 minutes ago, sevenperforce said:

As I understand it, Al grid fins can be reused after LEO re-entries but get torched in GTO re-entries. So there's no reason to use the new titanium ones on LEO launches, but if they are used on GTO launches then they are expected to be expended. (The grid fins, not the stage).

After GTO launches they could give the grid fins to museums or something. If there's no demand for that, I'd take one and make a table out of it.

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15 minutes ago, Ultimate Steve said:

After GTO launches they could give the grid fins to museums or something. If there's no demand for that, I'd take one and make a table out of it.

It's easy to forget the size of the rocket, even after watching so many launches...

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