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21
I caught a frame from John Randolph's video of something falling into the bottom section of the rocket but I

don't know how to show it? Huh, it worked? I hope no one got hurt!

Do you have a link for the video?

No it's on the face book site? I'm not computer literate. Just an old coot that only knows one thing.
It’s on the Boca Chica Facebook group.

https://www.facebook.com/groups/1541938906124567/permalink/2226348904350227?sfns=mo

22
I caught a frame from John Randolph's video of something falling into the bottom section of the rocket but I

don't know how to show it? Huh, it worked? I hope no one got hurt!

Do you have a link for the video?

No it's on the face book site? I'm not computer literate. Just an old coot that only knows one thing.
23
I caught a frame from John Randolph's video of something falling into the bottom section of the rocket but I

don't know how to show it? Huh, it worked? I hope no one got hurt!

Do you have a link for the video?
24
Electric melting of glass is not efficient, electric heat is not efficient in general, at least on earth.  A gas furnace can melt glass easier, unless solar can be concentrated directy on the silicone, or directly on iron, aluminum etc and can get hot enough.  The plant you referenced got the water to 550 C.  Pretty hot, but silicone melts at 1,400 C, while aluminum is 660 C.  Can a reflective solar plant on Mars get as hot as it does on earth?
Got to disagree on this:
http://ietd.iipnetwork.org/content/electric-melting
Electric furnaces are much more logical on Mars than gas fed ones, since the gas on MArs comes from electricity in the first place.
25
Delta IV Heavy Launch with NROL-71 through tracked telescope in 4K on 2019-01-19


Justin Foley
Published on Jan 20, 2019

The launch of United Launch Alliance Delta IV Heavy rocket from Vandenberg Air Force Base in California on January 19th, 2019.

This video is a combination of footage shot with a Sony A7sII through a 1500mm Celestron 6" Schmidt-Cassegrain telescope and a piggybacked Sony A6000 with 210mm telephoto lens. Tracking was guided manually via joystick control. Audio recorded with standalone tascam audio recorder.

The rumble is very low, and may only be able to be heard with larger speaker systems.

https://www.youtube.com/watch?v=PwuQMEZulGk?t=001

26
I caught a frame from John Randolph's video of something falling into the bottom section of the rocket but I

don't know how to show it? Huh, it worked? I hope no one got hurt!
27
...Well this is the type of periodic assessment that Congress is supposed to do with all major spending programs, but has not yet done with the SLS in it's 8 years of existence.

Not sure what you mean by "Congress" in this context.  Certainly the GAO has done several such assessments, often as requested and required by Congress.  Several over the last few years if memory serves.

The GAO has not been told by NASA how much the SLS will cost to operate, and NASA has not told Congress either. Those are significant costs that have not been identified for future programs, and are important for understanding if the SLS program will achieve whatever Congress wants it to achieve in the future.

And at such a review it would be natural for the cost of operating the SLS to be compared with commercial alternatives, but the real reason for cancelling or keeping the SLS will boil down to whether there are near-term U.S. Government programs that require it's capabilities. As of today there isn't, but that could change - or not.

Hence the need for Congress to review the program, because it's only a couple of years until the SLS will be operational, and there isn't anything for it to launch except for Orion test flights (which needs it's own congressional review too).
28
Extra part for hole on hopper...

And CRS16 F9 stage returned fished from the from sea.

Wouldn't this imply that the hopper is intended to be horizontal at some point? If the hole is a service hatch it looks like it will be accessed when the hopper is laying on its side.
29
Well, I saw a video where something fell into the rocket part with legs, perhaps a piece of lumber! I hope no

one was below or something breakable? They were moving a chunk of bulkhead with the crane when

something dislodged!
30
Two more comments, in response to some of the discussion:

1.  People keep assuming that additive manufacturing is a silver bullet.  While it can work fine for something small like a Super Draco, which is a very simple pressure-fed rocket, that doesn't mean it is going to scale up to a large, staged-combustion engine like Raptor, full of complex turbomachinery.  The size isn't the only problem, the mechanical properties of printed metals is eye-wateringly miserable.  That translates into a large weight penalty.

I've working on biggish (0.2m scale) laser sintered metal parts.  The mechanical properties are generally pretty close to the ideal annealed metal strength, and mostly heat-treatable alloys are used to allow even higher strengths to be attained.
 You can use titanium alloys, maraging steels and wrought superalloys all with extremely high strengths, and you can light-weight designs using small webs etc in ways that are simply not manufacturable by any other means. 
EG check out properties of wrought superalloy Inconel 718 (which I have used a lot): EOS 718 properties: https://www.eos.info/eos-nickelalloy-in718-nickel-alloy-for-aerospace-and-industry-d64f5c43276f3673

I know people working on much bigger laser sintered parts (0.5m scale), no problem with strength and with careful tweaking of build process no problem with distortion compared to competing processes like casting or forging.

Sure it is not suitable for every component and not suitable for every material (particularly heat treatable aluminum alloys), but is enabling a big step forward in weight and cost reduction for low volume aerospace manufacture, particularly for hard to machine and hard to join materials.  If they can use it to make the Raptor turbomachinery and preburner casings and even injector manifolds with all their large numbers of intricately shaped internal passages in only a few pieces then they will likely be able to save cost, manpower and maybe weight compared to more conventional casting and forging fabrication.
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