SpaceX And/Or Rocketry In General

archae86
archae86
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Once they turned off the

Once they turned off the audience mike and turned on the speaker's mike, the press conference is quite usefully audible.

If I understood Elon's account of the failure to land the center stage: it was meant to do a three-engine burn, but the two side boosters failed to light up--apparently for lack of sufficient TEA/TEB.  Naturally that meant the stage came in at considerable speed.  It was close enough to the barge to take out two of the positioning engines.  I'd guess, personally, that some of the deck load stuff (which is mostly in containers), may have been damaged also.  

archae86
archae86
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I highly recommend this

I highly recommend this amateur video of the first stage components of the flight:

https://youtu.be/59pY74ZhQ50

It was made using a mid-grade SLR camera mated to an LX200 telescope (the Meade version of the classic 8-inch so popular among amateur astronomers for decades).

It is especially strong in preserving the relative positioning of the components during booster separation and return.

 

Kavanagh
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Surreal. A mannequin looking

Surreal. A mannequin looking at the instructions for the Hitch Hikers Guide to the Galaxy (Don't panic). listening to A Space Oddity as he accelerates past 12000 km/hr. 

p.s. Seems the centre  core was lost due to a shortage of triethylborane.

Richard

Mike Hewson
Mike Hewson
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Ah, that I have lived to see

Ah, that I have lived to see such a thing ! :-)

Elon said the slight difference in side booster landing timing was deliberate and to avoid radar interference. Which/what radar I didn't catch. Does each booster use onboard radar in terminal approach ?

Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter ...

... and my other CPU is a Ryzen 5950X :-) Blaise Pascal

archae86
archae86
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Mike Hewson wrote:Does each

Mike Hewson wrote:
Does each booster use onboard radar in terminal approach ?

Radio altimeter, I think.  aka RADALT, radar altimeter...

Gary Charpentier
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archae86 wrote:Mike Hewson

archae86 wrote:
Mike Hewson wrote:
Does each booster use onboard radar in terminal approach ?

Radio altimeter, I think.  aka RADALT, radar altimeter...

I'm sure it isn't ground based and uplinked, so radar altimeter / Doppler velocity it must be.  Can't see him having some different in ground reflection as a position guide, video would be so much more accurate and they must have INS and GPS on already.  He could be using some variation of MLS but each pad would be on a different frequency.

Mike Hewson
Mike Hewson
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Elon : "Third burn

Elon : "Third burn successful. Exceeded Mars orbit and kept going to the Asteroid Belt."

Projected orbit : 

starman.jpg

.... now that is serious mojo.

Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter ...

... and my other CPU is a Ryzen 5950X :-) Blaise Pascal

archae86
archae86
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That initial set of orbital

That initial set of orbital parameters has been dialed back quite a bit.

Now: Corrected orbital data for the Roadster: 0.99 x 1.71 AU x 1.1 deg

Oddly C3 is still given as 12.0?!

The sum of the second stage burns was well below previous missions.  People are speculating that the long coast gave rather a lot of LOX boil-off, reducing total oomph.

In considering Falcon Heavy capability and price, it is worth remembering that the low-ball price is for a fully recovered set of first stage cores (two by land and one by sea), while the maximum capability performance numbers are for the case where all three cores get thrown away.

Booster recovery is really nifty, remarkably pretty, and should save a lot of money once they get the refurbishment process dialed way down, but it does cost a great deal of performance.

archae86
archae86
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The PAZ satellite launch from

The PAZ satellite launch from Vandenberg, with two test satellites for development of StarLink (SpaceX's planned dense low-earth-orbit comsat system) launched successfully on a Falcon 9 operating in expendable mode.

For the first time (I think) they tried actually to catch one half of the fairing, using a fast crew boat with a huge net rigged atop.  Elon tweeted that they missed by a few hundred meters this time, and shared this picture of the boat (former named Mr. Steven)  While a long time ago he spoke of possibly using something like a bouncy castle, he refers to this one as a catcher's mitt.

https://www.instagram.com/p/BfgHKDNAplx/

 

 

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