New Mars Forums

tahanson43206

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Registered: 2018-04-27

Posts: 19,383

In Praise of Magical Thinkng

Recently, one of our creative members indulged in a bit of Magical Thinking.

This topic is offered to provide a safe place for magical thinking.

The idea of stopping a bowling ball midway down the lane, performing maintenance on the exterior of the ball, and resuming travel down the lane toward the waiting pins is an example of magical thinking today.

However, in ** this ** topic, the words of Arthur C Clarke are the theme:

Google came up with these snippets:

In 1962, in his book “Profiles of the Future: An Inquiry into the Limits of the Possible”, science fiction writer Arthur C. Clarke formulated his famous Three Laws, of which the third law is the best-known and most widely cited: “Any sufficiently advanced technology is indistinguishable from magic”.
Nov 8, 2018
Any sufficiently advanced technology is indistinguishable from magic.
lab.cccb.org › arthur-c-clarke-any-sufficiently-advanced-technology-is-ind...
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(th)

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,383

Re: In Praise of Magical Thinkng

In this new topic, I'd like to acknowledge and offer appreciation for the idea of a "semi-cycler"

This is a huge space vessel that is able to manage it's momentum in orbit around the Sun, so that it can stop and start without using mass according to Newton's Laws.

This vessel is magical in 2023, but it may well be common practice in 2123, when the Laws of the Universe are better understood.

I do offer a prediction about whatever solution may be found ... it will involve the allocation of energy as great as or greater than would have been required to stop and start using mass expenditure in 2023.

(th)

Void

Member

Registered: 2011-12-29

Posts: 7,818

Re: In Praise of Magical Thinkng

But it allows access to resources from Mars/Phobos/Deimos to refill propellants.  As for energy, the sun is a nuclear reactor.

This ship will indeed have stored energy from its orbit of Mars which can be reused to partially get on a path to Earth.

In passing the Earth and not stopping, it can capture energy of momentum from the Earth itself.

You need raw materials, and energy is on such: https://www.esa.int/Science_Exploration … spacecraft.
Quote:

Let gravity assist you...
21/06/2013
25446 VIEWS
120 LIKES
ESA / Science & Exploration / Space Science / Exploring space
When a spacecraft launches on a mission to another planet it must first break free of the Earth’s gravitational field. Once it has done that, it enters interplanetary space, where the dominant force is the gravitational field of the Sun.

The spacecraft begins to follow a curving orbit, around the Sun, which is similar to the orbit of a comet. When this orbit brings it close to its target destination the spacecraft must fire a retrorocket to slow down and allow itself to be captured by the gravitational field of its target. The smaller the target, the more the spacecraft must slow down.

Sometimes passing a planet can result in the spacecraft being accelerated, even without the spacecraft firing any of its thrusters. This is known as the 'slingshot' effect.  Such 'gravity assist' manoeuvres are now a standard part of spaceflight and are used by almost all ESA interplanetary missions. They take advantage of the fact that the gravitational attraction of the planets can be used to change the trajectory and speed of a spacecraft.

The amount by which the spacecraft speeds up or slows down is determined by whether it is passing behind or in front of the planet as the planet follows its orbit.  When the spacecraft leaves the influence of the planet, it follows an orbit on a different course than before.

ESA’s comet-chasing Rosetta mission launched in 2004 and is using slingshot manoeuvres to reach its destination, Comet 67P/Churyumov-Gerasimenko, in 2014. It has received gravitational ‘kicks’ from close flybys of Mars (2007) and Earth (2005, 2007 and 2009). Rosetta has also made close flybys of two asteroids.

And I suspect that you can also use the Oberth Effect as well to get more power from your chemical burn.

The sun is with you almost all the time, so that is a source of energy.  The solar wind is a source of fast-moving mass.

To be sure the flyby of Earth and transfer of humans will have dangers, but then so would the Aldrin Cycler.  I have already suggested how to reduce the danger.  At least I made an attempt.  Jury is still out on that one.

Done.

Last edited by Void (2023-02-02 11:07:32)

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Void

Member

Registered: 2011-12-29

Posts: 7,818

Re: In Praise of Magical Thinkng

Dr. Zubrin as I recall, suggested an elliptical parking orbit of Mars.  And then landing a smaller ship.  The purpose of the Elliptical orbit is that it stores energy.  That is what I recall.  Hopefully I don't get burned for that assertion.  I don't think that that scheme was part of "Mars Direct" though.

This could be useful: https://en.wikipedia.org/wiki/Electric_sail
Quote:

Intrinsic limitations
Almost all Earth-orbiting satellites are inside Earth's magnetosphere. However, the electric sail cannot be used inside planetary magnetospheres because the solar wind does not penetrate them, allowing only slower plasma flows and magnetic fields.[citation needed] Instead, inside a planetary magnetosphere, the electric sail may function as a brake, allowing deorbiting of satellites.[24]

Like for other solar sail technologies, while modest variation of the thrust direction can be achieved by inclining the sail, the thrust vector always points more or less radially outward from the Sun. It has been estimated[by whom?] that maximum operational inclination would be 60°, resulting in a thrusting angle of 30° from the outward radial direction. However, like with the sails of a ship, tacking could be used for changing the trajectory. Interstellar ships approaching a sun might use solar wind flow for braking.[24]

There are other sails proposed.  Dr. Zurbin has at least one, and I believe that that one can maneuver in the Earth's magnetic field.

But the one above can brake into the Earth's magnetic field, and I anticipate that you can skip on it, to change your orbital path.

But back to Mars, the sail could move materials from low Martian orbit to higher Martian orbit, to supply the semi-cycler.

Before departure from Mars, it might be possible to bring the orbit of the semi-cycler all the way up to not quite escape, and to use a tether to spin the semi-cycler against another object (The Electric Sail?).  Then break the bond, sending the semi-cycler off to Earth and the sail down an elliptical orbit of Mars, which it could correct back to a different desired orbit.

So, solar wind energy could be stored in two spinning ships, and then released where one ship exits Mars, and one goes into a deeper Mars orbit.  But I don't know if the fuss is worth the trouble.  Maybe.

Done.

Last edited by Void (2023-02-02 11:21:20)

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