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SpaceX Falcon 9 FT launch - EchoStar 23 - LC-39A

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- Previous launch to LEO to Space Station, MECO happens at around 60 km altitude with a speed of 6000 km/hr at exactly T+2:25 minutes

- Current launch to GEO, MECO happens at 74 km altitude at 9500 km/hr at T+2.44

This time though the first stage was at 7200 km/hr at the same T+2:25 mark was burning for additional 10 seconds, at ended up with a much higher 9500 km/hr speed. So it seems there was more fuel and also was burning much faster with a lot more higher thrust.

wow, speed increase of 2300 km/hr in just the last 10 seconds. How many Gs is that ?
 
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Sorta weird that the star tracks look longer in my photo, even though I think I stopped my photo after MECO. (Well, it was cold out...) No idea why.
I noticed that too. My guess is the second photo was taken looking north while yours was more towards east. You can see in that photo that the streaks (arcs actually) are not at the same angle, and some stars don't have streaks at all.
 
The rocket equation is a bitch ! The last 1/3 of fuel gives the stage a much much bigger DeltaV than the first 2/3, because of the extra work to push the nearly full stage.
With Block V we should start seeing staging in the 7000+Km/h for ASDS hot landings.
I wonder if this booster was Block IV instead of Block III. Block IV gets some more thrust, then Block V gets even more (in theory final max thrust).
The higher thrust capability of successive blocks will result in substantial increases in staging speeds if pushing the same payload mass.
Part of the lower LEO mission staging is the total mass of Dragon + its payload. It is often twice the mass of GTO payloads.

- Previous launch to LEO to Space Station, MECO happens at around 60 km altitude with a speed of 6000 km/hr at exactly T+2:25 minutes

- Current launch to GEO, MECO happens at 74 km altitude at 9500 km/hr at T+2.44

This time though the first stage was at 7200 km/hr at the same T+2:25 mark was burning for additional 10 seconds, at ended up with a much higher 9500 km/hr speed. So it seems there was more fuel and also was burning much faster with a lot more higher thrust.

wow, speed increase of 2300 km/hr in just the last 10 seconds. How many Gs is that ?
You need to actually measure the time in the last launch from 7200km/h to 9500km/h.
You cannot assume the speed over time curve is the same between launches.
Although EchoStar XXIII was a very heavy GTO payload for F9, it was quite light compared to a fully loaded Dragon.
This impacts the entire acceleration curve.
But if the 10 second figure were true:
dv=640m/s
t=10s
a=dv/t=64m/s2
In theory that's 6.5g average.
I bet you the limit was 4gs and it was fully respected, 7200km/h was achieved around 7 seconds sooner, since for a 4g limit, 2300km/h would take 16.6 seconds to happen.
 
I noticed that too. My guess is the second photo was taken looking north while yours was more towards east. You can see in that photo that the streaks (arcs actually) are not at the same angle, and some stars don't have streaks at all.
Confirmation of BrassGuy's answer comes from examining the least-north stars in Richard's photo, and the furthest-north ones in BrassGuy's: their lengths approach each other.

Those of you who teach high school astronomy, mathematics, physics &c might consider using these two photos for a "Figure Out Why" moment. I have been thinking of saving the two pix for same.
 
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Timezone switch screws with applications sometimes too. Newer software developers often make mistakes relating to not taking time zone shifts into account. This usually manifests in the form of storing important timestamps in local time resulting in anomalies around the time zone shifts, especially in the fall where event timestamps can end up out of order due to time zone information loss. At my work, we usually store all timestamps in GMT, but of course, it's extra work to constantly convert them back and forth between GMT and local time.

Congrats SpaceX on successful launch. Keep up the great work!

Not much extra work in C: call localtime(). GMT (maintained by astronomers) was replaced by UTC (atomic clock) 40 years ago:)
 
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