Re: Overheard on the scanner

In article <g53llh$60i$1@xxxxxxxxxxxxxxxx>,
"Keith F. Lynch" <kfl@xxxxxxxxxxxxxx> wrote:

Joe Ellis <synthfilker@xxxxxxxxxxxxx> wrote:
"Keith F. Lynch" <kfl@xxxxxxxxxxxxxx> wrote:

The most efficient vehicle in pure joules/kg/km is the International
Space Station. It took a lot of joules to put it in orbit, but it's
traveled a tremendous number of kilometers since then.

But not without additional orbital adjustments from its on-board
engines.

True, but that's negligible compared to the energy it took to launch
it in the first place.

Not when they're _absolutely_necessary_ to _keeping_ it in orbit.

I'd wager Voyager has it substantially beaten. After all, it got a
lot of its velocity boost for free via slingshot maneuvers, and it's
been flying faster, longer.

I'm not so sure. It was certainly going faster than ISS ever has,
even before the slingshot maneuvers, but that may count against it,
since the minimum necessary launch energy increases with the *square*
of the speed. Not to mention the energy it took to escape Earth's
gravity in the first place, which ISS hasn't done.

Not very efficient then after all, is it? It's only reached about 200
miles altitude.

And I'm not sure that something that doesn't carry a person should
even count. Otherwise why were we talking about cars, pedestrians, and
bikes, but not about birds or ants or dandelion seeds? Or photons?

Perhaps because YOU specified "vehicle" without saying a word about
"passenger carrying"... and now are trying to weasel out of it.

A vehicle is something transporting "people OR GOODS"... and the
experimental packages about Voyager certainly qualify as "goods". And
yes, several of them are still operating. Not to mention the digital
disk carrying "greetings from Earth" to wherever it ends up.

The Voyager spacecraft have been traveling since 1977. With that head
start, the ISS will NEVER catch up unless the Voyagers meet with a
disastrous misfortune of some kind... like another Robert Wise movie.


http://en.wikipedia.org/wiki/Voyager_1

--
"The Dream is Alive! Music of the Space Shuttles" now available at your
local filk dealer, at http://cdbaby.com/cd/joeellis, and as a digital
download on iTunes at http://preview.tinyurl.com/yd7gns
.

Relevant Pages

  • Re: Hubble Marching orders
    ... One reason for this is that the space station was ... It's Dead, Greg. ... ISS and just shut down the program and Shuttle now? ...
    (sci.space.policy)
  • Re: NASAs Moon base plans
    ... Opposition to the ISS seems relatively circumscribed--not ... opposition to a space station in the abstract, ... disastrous both for morale and credibility to keep having massive cost ...
    (sci.astro.amateur)
  • Re: DOUBLE FLYBY ALERT
    ... Check http://spaceweather.com to see if you are favored with a double flyby of your hometown before Discovery returns to Earth on Thursday. ... DON'T MISS THAT FLYBY: Would you like a call when the ISS is about to fly over your area? ... The Shuttle will come from the southwest, pass close to overhead and move away to the east. ... The ISS (Space Station) is supposed to be about a minute behind on approximately the same track. ...
    (sci.astro.amateur)
  • Re: SpaceX vs. Japan
    ...  This would accomplish ...  If launches take place from Wallops Island, ... ISS became international during ... "Freedom" space station. ...
    (sci.space.policy)
Loading