Re: [Starlink] Starship's 4th flight test was magnificent

[David Lang <david@lang.hm>]

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Alexandre Petrescu wrote:

>> Also, during reentry, the plasma tha builds up blocks any radio down to the 
>> ground, and with anything other than a starlink, it even blocks radios up 
>> to satellites.
>
> I did not know they use plasma to propel that rocket.  Actually I dont know 
> much about how these things can be propelled, but I know that with these high 
> speed objects photos one can see many things like 'aura' or 'glow'  or even 
> 'glory' in the certain light conditions.  If that is 'plasma' then that could 
> be it.

it's not propelled by plasma, but as it's reentering, the air can't get out of 
the way and gets compressed into plasma. Watch the flight test 3 and 4 videos, 
at about the 45 min mark as it gets down below ~120Km you start to see a glow 
build up. That is the air being compressed into plasma around the ship.

with the typical small capsules, it wraps around the capsule to completely 
encose the capsule and results in zero (or close to it) communications during 
the most dangerous part of the reentry.

The combination of the Starship size and the Starlink capability means that 
these two flights are the only ones in history where we have a real-time feed 
through the hottest parts of the flight. We have recordings from other flights, 
but until they slow down, no way to get the data out of the spacecraft.

David Lang