Author Topic: SpaceX FH : Falcon Heavy Demo : Feb 6, 2018 : Discussion Thread 2 (Read 598025 times)

Phil Stooke · « **Reply #1060 on:** 02/08/2018 02:01 am »

"So the photo is actually 'upside down' "

I think it was the camera that was upside down. The image is OK when the camera orientation is corrected. Or is it? Wait - there is no 'up' out there so no upside down either. You can view it any way you like.

Citabria · « **Reply #1061 on:** 02/08/2018 02:26 am »

Updated orbital period is 1.57 years. Should pass near Earth in 11 years (7 orbits).

BradyKenniston · « **Reply #1062 on:** 02/08/2018 02:27 am »

A look at plume size: Falcon 9 vs Falcon Heavy.

tvg98 · « **Reply #1063 on:** 02/08/2018 02:32 am »

There's some interesting acoustics in this video during Falcon Heavy's ascent. Any clues as to why it sounds the way it does?

georgegassaway · « **Reply #1064 on:** 02/08/2018 03:21 am »

Quote from: tvg98 on 02/08/2018 02:32 am

There's some interesting acoustics in this video during Falcon Heavy's ascent. Any clues as to why it sounds the way it does?

Suspect the high pitched “twang” sounds were produced by other things near the camera, which were vibrated by the launch acoustics. Maybe as simple as the leaf fronds of the Palm Tree. Or perhaps some nearby tensioned cables responding in a manner not too unlike tapping with a hammer (or nearby cables attached to structures vibrated by the launch). Or the metal siding on the buildings.

Once nearly had a small tornado hit our house, there was a definite massive wind gust for a few seconds and we heard a high pitched screeching from the leaves of a tree next to (and upwind of) the house…. just before a limb broke off and hit the roof. Not the same thing as launch acoustics, totally different tree leaf types and such. But seeing that Palm Tree, and this unique sound, reminded me that leaves can produce some incredible noises. Though the tensioned cable theory was what first came to mind (Did not think of the buildings since those were not seen till briefly near the end).

Okie_Steve · « **Reply #1065 on:** 02/08/2018 03:22 am »

Quote from: CameronD on 02/08/2018 01:30 am

Quote from: cebri on 02/07/2018 09:35 pm
Yes, it's the camera mount. You can see it here too.

Love the "Don't Panic!" on the center console display. Links back to the front cover of "The Hitchhiker's Guide to the Galaxy".. Very cool of them to think of that!

Makes me wonder how long the Tesla " avionics" will/did last going through the belts and then out of LEO.

JimO · « **Reply #1066 on:** 02/08/2018 03:26 am »

Here's Derek Breit's message on satobs.org with his video that shows what I measured was a 52-second burn-3. I still can't figure how a single Merlin engine can make a twin plume pattern. The deorbit engine burn observed over the Persian Gulf last year only showed a single plume but that could be an artifact of the booster's roll orientation.

I have added the full video to my Gallery page, Which contains an equal amount of video previous to the Burn.. This is posted to help with any positions people would like to derive.. Bottom right of.. http://www.poyntsource.com/New/Gallery.htm 256 MB !!!
Video shot from my front yard in Morgan Hill, CA.. Time is exact, though the Camcorder - used only as a VCR - needs cleaning.. The Quadruple star that is at the lower left of center at the start of the video.. The brightest star is.. Mag 3.5 Dheneb in Cetus.. Orientation is Normal Eyeball.. Derek Breit BREIT IDEAS Obs

breit_ideas_at_poyntsource.com

Space Ghost 1962 · « **Reply #1067 on:** 02/08/2018 03:35 am »

Quote from: tvg98 on 02/08/2018 02:32 am

There's some interesting acoustics in this video during Falcon Heavy's ascent. Any clues as to why it sounds the way it does?

I'd noticed the profound difference in Falcon's sound both at CCAFS and VAFB compared to Atlas/Delta launches.

(Note that same LV launches also "crackle" and echo differently depending on the seasonal / environmental issues, so you have to factor that out too.)

Falcon 9's seem to "hum" more than the more "throaty" RD-180, as if the commonality of all of the engines mean they tend to all be "tuned" to the same pitch, but because combustion is highly chaotic, they are all being randomized to some degree, with a common mode that they tend to return to in phase resonance.

Perhaps with 27 engines, the common mode dominates, and the varying spacing between the acoustic waves (sources are varying in relative location/orientation) form transient acoustic caustics that you hear in the above audio track?

cletus · « **Reply #1068 on:** 02/08/2018 04:55 am »

Full 4+ hour Starman video is up now:

(Over 10 million views on a video that doesn't even have sound!)

I wonder if it would be possible to collect all the frames from when the earth is centered in the frame, align them, and just get a continuous time lapse of the earth receding. Any takers?

tvg98 · « **Reply #1069 on:** 02/08/2018 05:11 am »

Another video of the injection burn. It's quite short but at least you can see the plume quite well.

Kenm · « **Reply #1070 on:** 02/08/2018 05:17 am »

Quote from: georgegassaway on 02/08/2018 03:21 am

Quote from: tvg98 on 02/08/2018 02:32 am
There's some interesting acoustics in this video during Falcon Heavy's ascent. Any clues as to why it sounds the way it does?
Suspect the high pitched “twang” sounds were produced by other things near the camera, which were vibrated by the launch acoustics. Maybe as simple as the leaf fronds of the Palm Tree. Or perhaps some nearby tensioned cables responding in a manner not too unlike tapping with a hammer (or nearby cables attached to structures vibrated by the launch). Or the metal siding on the buildings.

Once nearly had a small tornado hit our house, there was a definite massive wind gust for a few seconds and we heard a high pitched screeching from the leaves of a tree next to (and upwind of) the house…. just before a limb broke off and hit the roof. Not the same thing as launch acoustics, totally different tree leaf types and such. But seeing that Palm Tree, and this unique sound, reminded me that leaves can produce some incredible noises. Though the tensioned cable theory was what first came to mind (Did not think of the buildings since those were not seen till briefly near the end).

Similar sound here

Looks like an open field but we don't see whats behind the camera.

MJW · « **Reply #1071 on:** 02/08/2018 05:38 am »

My only regret about this amazing achievement is that there wasn't enough battery power on the Tesla to leave the left blinker on all the way to the asteroid belt.

Steven Pietrobon · « **Reply #1072 on:** 02/08/2018 05:45 am »

Quote from: Johnnyhinbos on 02/08/2018 01:33 am

And photoshop’d. In the very least the driver side camera bracket was airbrushed out. Wished they just left it real. Now I look at it and wonder just how touched up it is...

Here's an enhanced image. There is a lighter area to the right (R,G,B) = (2,2,4) and (2,1,6). Looks like the right camera has been rubbed out. They should have used the same dark pixels as in deep space of (2,0,3). You can also see where the shadow of the car crosses diagonally at the bottom of the lighter area. Also see some darker (2,0,1) imaging artefacts possibly from an imperfect CCD chip. Maybe its a secret message! :-)

ames · « **Reply #1073 on:** 02/08/2018 06:27 am »

Quote from: tvg98 on 02/08/2018 02:32 am

There's some interesting acoustics in this video during Falcon Heavy's ascent. Any clues as to why it sounds the way it does?

Could be the sharp crack sounds reflecting from corrugated siding.
Try clapping as you walk past some.
"Pew pew"

cletus · « **Reply #1074 on:** 02/08/2018 06:32 am »

Quote from: cletus on 02/08/2018 04:55 am

I wonder if it would be possible to collect all the frames from when the earth is centered in the frame, align them, and just get a continuous time lapse of the earth receding. Any takers?

I guess this is close:

https://twitter.com/DJSnM/status/961490500397092864

Cinder · « **Reply #1075 on:** 02/08/2018 06:36 am »

Quote from: Steven Pietrobon on 02/08/2018 05:45 am

Quote from: Johnnyhinbos on 02/08/2018 01:33 am
And photoshop’d. In the very least the driver side camera bracket was airbrushed out. Wished they just left it real. Now I look at it and wonder just how touched up it is...

Here's an enhanced image. There is a lighter area to the right (R,G,B) = (2,2,4) and (2,1,6). Looks like the right camera has been rubbed out. They should have used the same dark pixels as in deep space of (2,0,3). You can also see where the shadow of the car crosses diagonally at the bottom of the lighter area. Also see some darker (2,0,1) imaging artefacts possibly from an imperfect CCD chip. Maybe its a secret message! :-)

If the original post wasn't joking, then you just need to look at the video. The driver side mount is visible in reflection there, as well IIRC as other structural bits on the car's undertray right near the edge of the frame.

edit- 11min into the video referenced here - https://forum.nasaspaceflight.com/index.php?topic=44778.msg1785601#msg1785601
Mods feel free to delete this post if I just missed the sarcasm, or something.

eeergo · « **Reply #1076 on:** 02/08/2018 07:20 am »

Quote from: cletus on 02/08/2018 04:55 am

I wonder if it would be possible to collect all the frames from when the earth is centered in the frame, align them, and just get a continuous time lapse of the earth receding. Any takers?

Something like this?

ugordan · « **Reply #1077 on:** 02/08/2018 07:26 am »

Check out the rapid change in the soot pattern on the LOX tank starting at 1:44 into the video.

ugordan · « **Reply #1078 on:** 02/08/2018 07:31 am »

Quote from: tvg98 on 02/08/2018 02:32 am

There's some interesting acoustics in this video during Falcon Heavy's ascent. Any clues as to why it sounds the way it does?

That might be the same spot as in this video:

And that weird sound you hear is windows flexing, you can see it at the end of the video posted above.

tvg98 · « **Reply #1079 on:** 02/08/2018 07:36 am »

Quote from: ugordan on 02/08/2018 07:31 am

Quote from: tvg98 on 02/08/2018 02:32 am
There's some interesting acoustics in this video during Falcon Heavy's ascent. Any clues as to why it sounds the way it does?

That might be the same spot as in this video:

And that weird sound you hear is windows flexing, you can see it at the end of the video posted above.

Interesting. I don't recall ever hearing the windows flexing in other launch videos, though that just might mean I haven't watched enough of them!