Humor XKCD vs Orbital Mechanics

[80mileshigh]

What's wrong with this cartoon (read the mouseover text)?

http://xkcd.com/787/

And by starting this thread I've become an XKCD character:

http://xkcd.com/386/

 

[Star Voyager]

The orbit seems too equitorial given the coordinates they describe. But in the background, it looks like a 50 degree orbit (?).

 

[80mileshigh]

The mistake is in the mouseover text (let your mouse linger on the cartoon and it will pop up).

 

[Urwumpe]

It is actually pretty wrong. You can launch up to 57° from KSC, if you exploit the extreme 35° launch azimuth.

Which means the shuttle passes right over everything between 57° North and 57° South. Passing over both points isn't even very hard...if I estimate correctly, you could actually find an orbit which passes both places without a full orbit between them. (first passage is north->South, second passage is South->North)

 

[Star Voyager]

The mistake is in the mouseover text (let your mouse linger on the cartoon and it will pop up).

Wasn't that my answer (essentially, more or less)?

It is actually pretty wrong. You can launch up to 57° from KSC, if you exploit the extreme 35° launch azimuth.



Which means the shuttle passes right over everything between 57° North and 57° South.

But that would take awhile going from passsing over Israel to passing over Oklahoma.

 

[Urwumpe]

But that would take awhile going from passsing over Israel to passing over Oklahoma.

Not really - both places are just 118.9° apart in latitude. Earth rotates by 22.5° per Orbit, additionally you can have a drift by non-spherical gravity.

 

[80mileshigh]

Wasn't that my answer (essentially, more or less)?

Sorry if I misunderstood you.

Urwumpe said what I was thinking. The point is, his claim that a normal 'safe' shuttle orbit cant pass over those points is incorrect. He's a physics grad and ex-NASA Langley. I'm a history student so I'm obliged to call him out on this after: http://xkcd.com/755/ (mouseover test again) :lol:

 

[Lucy]

... Have I mentioned how much I love you all recently?

Seriously, this has to be the only place on the internet where a webcomic can spark such a discussion. <3

 

[80mileshigh]

...Well I did think of posting at the XKCD forum but I like it better here.

Assuming the 'safe' orbit = [email protected] ...

Orbitron says: next ISS pass over Jerusalem = 20:27 UTC, and over Oklahoma City (or, if your prefer, occupied North Texas) = 21:36 UTC.

EDIT: ... which means of course, that urwumpe is correct. The Jerusalem pass is the descending node and the Oklahoma pass is the ascending node of the one orbit.

 

[IgnoreThisBarrel]

NO!!! I was wrong in the "You know you're addicted to Orbiter" thread