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14

It's theoretically possible; the velocity of the exhaust plume is around 3000 m/s (pretty close to what you'd need for a translunar injection!) and the mass flow rate is ~270 kg/s, so if a small piece of debris fell off the stage into the plume, it could get quite a boost. It seems a little unlikely that a piece big enough to track would get kicked up in ...


11

Sorry, no bulb-shaped exhaust plume, at least not in true vacuum. But you might see something similar to an incandescent light bulb shaped exhaust plume at high altitudes that first stages reach, up to about 135 km high (exact altitude depends on launch vehicle and its ascent profile) above sea-level where there is still some, albeit tenuous atmospheric ...


10

Those are Mach diamonds. They form due to the interaction of the exhaust flow with its own supersonic shockwaves. All rockets and some jet engines produce them; their visibility varies with the propellant combination, mixture ratio and environmental conditions. The flow pattern doesn't appreciably affect thrust since it takes place after the exhaust has ...


5

SN10 like all recent Starship prototypes is very over powered. It has 3 Raptor engines each capable of producing in excess of 200 tonnes thrust and for safety reasons it also takes off with a fairly limited amount of propellants and burns through them at a rapid rate. Consequently it is necessary to throttle down and then power down the engines one by one. ...


4

Why, they look like this :) Here's an image of 3 rocket engines firing simultaneously on the Orbiter. (up, right, and aft firing RCS jets) Nota bene: the sorta-rectangular object just above the right-firing jet is a reflection in the window through which the image is being taken.


3

We watched the launch live from about 60 miles north of the launch site. I also had the live feed on my phone. As the first stage separated, the thrusters fired to change the orientation of the vessel. Allowing for video lag, the puffs we saw live were matched with the seconds-later video. The video lacks "real life" resolution. We saw numerous arc ...


3

I checked the CRS-6 launch (which launched at daytime, so you can see more on the video). Around T+1m, the camera pans up and you can see vapor coming out of at least two ports at the top of the first stage. These ports are 90 degrees apart, so they aren't both umbilical connections. In the Jason-3 launch, you can see these plumes before liftoff (this ...


3

Since this question was posted, plenty of exhaust plumes have been filmed from the ground giving a nice impression of the long term expansion behavior. So, no, I wouldn't call it bulb shaped, but yes, the exhaust expands in ...


3

The most probable answer to date offered for the observed sky feature is the NROL-61 rocket launch. Specifically, a fuel dump from the Centaur stage of the multistage launch, as part of the Centaur's decent procedure back to Earth. As this Satellite is intended for high geostationary orbit, multiple rocket stages are required. This view comes from the ...


2

Not sure but it was probably the NROL-61 launch. A spy satellite for the US National Reconnaissance Office was launched at 1237 GMT July 28 from Cape Canaveral. I don't know its exact orbit so I can't say for certain whether or not it was what you saw but the spy satellite would have been performing a periphrasis raise maneuver in the vacinity of Australia ...


2

Here's my take at an explanation of the base force - in words and pictures! Here we see Block I ShuttleTM sitting on the pad, engines off. The sea level atmosphere surrounds it everywhere and all pressure forces sum to zero. Immediately after liftoff there is a large "bubble" of reduced pressure under the vehicle because of complicated plume effects, ...


1

The orange color indicates they're running fuel-rich. With the methane/oxygen ratio out of whack there would be more carbon in the exhaust which burns orange. It's possible that engine was malfunctioning. SN10 aborted at T-0.1s because one engine was producing too much power. They decided to reset the systems and launch anyway. When transitioning into hover, ...


1

Scott Manley did a video on this from SAOCOM. It basically seems to be some characteristic of the pintle injectors inside the engine, which leads to the unusual shape seen in the rocket plume. See his video for more details.


1

The chemical energy from burning 1 mole (2 grams) of hydrogen in plentiful oxygen is 242 kJ. Just enough oxygen is half a mole, or 16 grams. The Space Shuttle external tank contained 629,340 kg of liquid oxygen and 106,261 kg of liquid hydrogen. Note that this isn't enough oxygen to burn all the hydrogen, for rocket science reasons, so we'll figure out the ...


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