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SpaceX Launch Last Year Punched Huge, Temporary Hole In the Ionosphere (arstechnica.com)
The Falcon 9 rocket that launched last August reportedly ripped a temporary hole in the ionosphere due to its vertical launch, which Ars Technica notes as being rather unusual: Contrary to popular belief, most of the time when a rocket launches, it does not go straight up into outer space. Rather, shortly after launch, most rockets will begin to pitch over into the downrange direction, limiting gravity drag and stress on the vehicle. Often, by 80 or 100km, a rocket is traveling nearly parallel to the Earth's surface before releasing its payload into orbit. However, in August of last year, a SpaceX Falcon 9 rocket launch from California did not make such a pitch over maneuver. Rather, the Formosat-5 mission launched vertically and stayed that way for most of its ascent into space. The rocket could do this because the Taiwanese payload was light for the Falcon 9 rocket, weighing only 475kg and bound for an orbit 720km above the Earth's surface. As a result of this launch profile, the rocket maintained a nearly vertical trajectory all the way through much of the Earth's ionosphere, which ranges from about 60km above the planet to 1,000km up. In doing so, the Falcon 9 booster and its second stage created unique, circular shockwaves. The rocket launch also punched a temporary, 900-km-wide hole into the plasma of the ionosphere.
Why does a perpendicular penetration create a bigger hole than a (much longer) almost parallel traversal?
One does not simply invent a space elevator!
Space elevators require unobtanium to have reasonable masses (they also have serious problems with damping oscillations, and their throughput is tiny in comparison to their mass, and they're inefficient, and slow, and about fifty other things). If you want something along that vein which doesn't require unobtanium, try a launch loop.
Is your job to sit under bridges and jump out at unsuspecting travellers?
".. still they are damaging to our eco system."
Are they? I didn't see anything indicating that in the article, nor anything stating how long the hole remained except to call it temporary. What damage are you claiming? Should California sue SpaceX?
Just another day in Paradise
This is simply not correct. The specific strength of the cable material determines the taper ratio. For anything with a worse specific strength than carbon nanotubes, you get a very high taper ratio that yields completely unreasonable masses - but you still can get a space elevator if you can magic all of that mass into existence in space. Even with carbon nanotubes the infamous Edwards analysis has to "fudge" a lot to make things work (and he assumes CNTs nearly twice as strong as individual CNTs have ever been measured, much less CNT "ropes" (microbundles), much less entire space elevator ribbons.
Is your job to sit under bridges and jump out at unsuspecting travellers?
The problem is the taper rate is actually exponential rather than linear, and if your strength-to-weight ratio isn't high enough, like steel for instance, then before you reach geostationary orbit your cable has to be wide enough to completely encase the Earth in a giant steel shell just to be able to support it's own weight.
Which, admittedly would then be much more capable of supporting its own weight, so you COULD do it if you were able to magic up several times the Earth's mass in steel. But I would have some pretty serious objections to the idea of completely blocking off the Earth from the sun, moon, and stars.
--- Most topics have many sides worth arguing, allow me to take one opposite you.