Caption: This is a schematic of displaced geostationary orbit. Credit: Advanced Space Concepts Laboratory, University of Strathclyde
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Posted on 07/26/2010 6:43:13 AM PDT by decimon
Caption: This is a schematic of displaced geostationary orbit. Credit: Advanced Space Concepts Laboratory, University of Strathclyde
Usage Restrictions: None
Orbituary ping.
Which is code for agenda-driven science.
Shame, because the technique is interesting. However it's just going to be used for/funded by more climate garbage.
Forward himself appeared to be pretty pro capitalist in his sci fi writings. The very first sentence in Saturn Rukh is “Got a job for you, it pays a billion.”
Scots engineers prove space pioneer’s 25-year-old theory (displaced orbits for satellites)
Wait! Could there be a spaced-out connection to Displaced Immigrant Alien Travelers found in the in the Arizona wilderness by U.S. Park Rangers??
Ping.
Issac Asimov used the name Dr.Robert Forward in a humorous story,probably not the same one as in this story he made one of his usual puns with the name Forward
That was my impression as well. I really enjoyed his sci fi novels, and my first thought when he died a few years back was pretty selfish: no more new Forward novels for me to read.
In the very first page of Saturn Rukh he speaks of the “greenie organization, the peaceful planet protectors against the further development of mars”.
Just to put things in perspective: at GEO altitudes, a 50 km displacement corresponds to a truly insignificant 0.07 degrees in elevation.
They'd need to get about 10 degrees of elevation shift for this idea to have any practical utility.
I seriously doubt they're anywhere close to that.
The real use of these orbits is increasing the number of geosynchronous satellite slots by 3X. They could also provide better comsat coverage at high latitudes.
The ref to climate change was probably put in by some NASA PR twinkie.
The basic science is not “agenda driven”; it is really useful science for comm apps.
BTW, I had the honor of meeting Dr. Forward and contributing to one of his projects in a minor way. He had a contract from USAF to check out inertialess drives and other far-out space propulsion ideas.
He found that almost all of the novel ideas were BS or violated the laws of physics. However, he found two winners: tethers and antimatter drives. Either of those could revolutionize space travel.
If you’re going to keep station over a pole, you’re going to be sitting there with no orbital momentum. This means that the always-present weight vector, pointing at the center of the earth, will have to be counteracted with an equal amount of upward thrust from some source or another, for the entire lifetime of the satellite.
(Of course, the higher the altitude, the less the weight for a given mass, and therefore the less the required thrust.)
It’s by no means obvious how they can utilize solar pressure in the polar sitting-case, since its force is always directed at 90 +/- 22 degrees from the needed direction. Converting that force into thrust using an ion engine, for instance, that could (1) Counteract the sunlight force itself, and (2) Provide levitating force equal to the weight of the satellite, would seem to violate the laws of Physics.
I can conclude only that they are assuming the presence consumable fuels onboard. But how long could such a satellite remain on station given the levitating impulse (thrust * time) available from any present or achievable or proposed, thruster technology? In terms of thrust alone, no presently achievable ion engine would even be close to supporting its own weight (even at, say, 40 000 KM), much less the weight of a practical satellite.
** Side note: Let us define a “classical” orbit as being one where the satellite is not subjected to external forces. This means that the orbit will be planar, with one focus at the center of the earth. (This leaves aside the secondary effects of solar pressure, drag from micro-atmosphere, and tidal irregularities from the earth, moon, and other massive objects.)
Now consider the case of a geosynchronous orbit in the plane of the equator. To “levitate” this orbit so that it follows a line of latitude away from the equator takes increasing amounts of thrust (power). The extreme case is considered above; viz., the polar-sitting case.
I’m really annoyed that the author uses “Geostionary” when they should use “Geosynchronous”.
Yeah I learned about the nanotube thethers from his fiction. Very interesting and novel idea for climbing into and out of gravity wells.
Does this really “prove” anything? Seems to me a satellite with a solar sail in a stable orbit would be a lot more like “proof.”
Isn’t the EIB Satellite in “Geosynchronous Orb”?
Who else where ye' expectin'?
CC
” a conventional electric propulsion system”
um...that is going to take a long extension cord...
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