What's Behind your Motivation to get High MPG?

[ChewChewTrain]

Originally Posted by niky

A good-sized solar sail should allow you to save fuel on braking... Or you could use the solar wind collected by the sail at your destination for reverse thrust.

Gonna need an incredible amount of fuel to do the pulse-pivot-pulse with continuous thrust throughout the trip.

Okay. Since everyone is getting serious about saving fuel between galaxies...

Why waste the fuel to slow down? Can't we just re-enter the atmosphere, use the air friction drag, and simply glow red hot for just a few hours?

[Fat Charlie]

Well, if you have enough mass to absorb that heat, you'd have too much mass to decelerate enough before you run out of atmosphere.

[NeilBlanchard]

I drive as efficiently as possible to save energy, to reduce my contribution to changing the climate.

[jamesqf]

Originally Posted by ChewChewTrain

Why waste the fuel to slow down? Can't we just re-enter the atmosphere, use the air friction drag, and simply glow red hot for just a few hours?

Actually used for space probes - see aerobraking. Problem is that at interstellar speeds, you run out of atmosphere before speed, and either go zipping past or have an opportunity to perform lithobraking :-)

[freebeard]

I really don't get all that good mileage. But I'm air-cooled so I get infinite miles per gallon of antifreeze. Antifreeze is poisonous to puppies and kittens.

I like to imagine I'm a happy little air molecule, when along come a Superbeetle, it's nose to the ground buzzing like an angry hornet. Someday soon it will be an silent Arcimoto SRK.

It's funny the thread runs to interstellar reach.

[IamIan]

In order of priority for me:

1. Energy efficiency
2. Sustainability
3. Interesting/Fun Engineering/Science

- - - - - - - -

As for interstellar travel ..

I don't expect any society technologically advanced enough to be able to do it .. to have any interest in doing it .. in the classical sense anyway .. I only see 2 possible exceptions .. and in any event absolutely no interest in us at all.

#1> Whole Society in Generation Ships:
If your species / society survives for enough billions of years .. in order to continue to survive you would eventually have to turn to at least generation ships .. but these don't need to 'travel' any faster than just slowly getting to the next resource extraction site every couple billion years or so ... sit at the new resource collection site for a few billions years before eventually taking a few billion more years to travel to the next ... etc .. no FTL space ships zipping around is ever needed nor desired.

#2> Dark Energy Drive:
The gist of the theory of dark energy is that empty space itself contains a form of energy and applies a negative pressure (ie a push/expansion of the space-time itself) .. it's one explanation for the accelerating expansion of the observable universe .. Relativity's Speed of Light limit doesn't apply to the movement (expansion) of space-time itself .. Instead of a 'Warp Drive' which has to spend very large amounts of energy to bend/warp the existing space-time .. a Dark Energy Drive .. consumes/converts the space in front of it (as an energy source) .. and in so doing there is then less space (ie distance) in front of that object ... In this way traveling long interstellar distance doesn't 'cost' you energy at all .. it gathers / extracts energy ... the further you travel the more energy you can gather .. the faster you go the faster you can gather more energy .. Dark Energy is estimated to be the largest energy source in all of the observable universe.

[freebeard]

Dark Energy is an illusion caused by misinterpreting the causes of red-shift.

Scientists now admit that there are plasma portals that open between the Sun and the Earth (every 8 minutes?) that allow particles to tunnel through the normal Solar wind.

As above so below; there will be similar portals that operate on interstellar and intergalactic scales. So it will be like the bodies zipping through transparent intestines like in Galaxy Quest or Hitchhiker's Guide to the Galaxy. One of those, or both.

[IamIan]

Originally Posted by freebeard

Dark Energy is an illusion caused by misinterpreting the causes of red-shift.

That would be another... ie 2nd

And a 3rd .. Is that even if the redshifts are interpreted correctly .. ie far away objects are moving away from us at an accelerating rate .. even then .. DarkEnergy is still only one explanation for the cause of that acceleration .. there are other explanations that don't require any DarkEnergy at all.

etc.

Yes .. Astrophysicist don't just use redshifts alone ... but the other methods used , also have the same kinds of alternatives described above as well...

DarkEnergy is one popular explanation that has been offered .. Not my own personal choice .. but it is one of several offered possible explanations.

[spacemanspif]

Becuase I like to play with cars and usually ecomodding costs much less than modifying my other car to go fast. So it scratches my wrench itch and hopefully puts a few more pennies in my pocket in the process.

Save fuel in one car to buy go-fast parts for the other

[freebeard]

Originally Posted by IamIan

DarkEnergy is one popular explanation that has been offered .. Not my own personal choice .. but it is one of several offered possible explanations.

Mine would be the Electric Universe theory. The Suspicious0bservers/thunderbolts.info crowd. Because it's predictive—things like the flash of white light when they impacted a copper slug into that comet—and the supporting evidence from the oldest petroglyphs in the world.
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Driving efficiently maximizes the return on the parts I put into my weekly driver.