# Tag Info

49

Spacecraft and space suits do NOT generate a magnetic field for medical reasons. Any magnetic fields generated are side effects of using electric motors etc. The linked question on Skeptics thoroughly debunks the idea, noting that: Gagarin was not in "critical condition" after his flight; and, Any flights in LEO are well within Earth's magnetic field. ...

44

Without a magnetic field any changes we do are seemingly temporary. As we make atmosphere it will be torn away by double solar winds. Double solar winds are the worst, occurring about 15% of the time this occurs when a faster solar wave catches a slower and rolls into one bigger wave. And these happen frequently, very frequently! First Edberg and his ...

26

Since the question states that the answer can be "hypothetical": Since the core of Mars does not have enough heat to start the convection process, we can drill a hole to the solid core and connect them to a source of electricity, and pass a huge current so it heats up ($\textrm{Heat}~=I^2*\textrm{Resistance of core}*\textrm{Time of passage of current}$) the ...

25

Yes, the research on shielding from energetic particles of solar wind plasma using dipole magnetic field continues, and perhaps the best indication of that is the filing of the Spacecraft shield patent (1) in 2010, roughly 2 years after the publication of the Plasma Physics and Controlled Fusion journal (2) that was noticed by the author of that Physics ...

24

There are some very good ideas. This requires a multiple answer approach. This can not be resolved by one method only. I don't believe mass is the issue (if) the iron core is large enough in comparison to the over all mass of the planet. If that is the case then re-starting the mantel is within our current technology to do. We may be able to reach and ...

22

Earth's magnetic field is way too weak to repel against with the force required to launch anything into orbit. Actually, it's really easy to demonstrate that. Take one fridge magnet, place it on the kitchen scale, and write down its weight. Then turn the magnet around and weigh it also with its polarity reversed. You shouldn't see any difference and the ...

22

Using liberally "The Case For Mars" second edition. Here's a few facts that help out in the discussion. There is substantial Carbon Dioxide at the poles, which if all of it melted, would thicken the atmosphere considerably. The theory is current that a 4 degree centigrade rise in temperature in the South Pole (Sustained) would trigger a run away greenhouse ...

21

Well, an electric motor is arguably a 'pulsed magnetic device', as is a solenoid valve, but good ones try very hard to contain the fields to where they will do useful work. I suppose one could design a suit without any motors, and it may even have been done, but pumps, blowers and valves and such seem a sort of natural feature of a space craft life support ...

19

It's Monday, so let me rain on this parade a little. Current magnetic shield designs are adequate to protect against ionizing radiation from the sun. They aren't sufficient to protect against galactic cosmic radiation, which has a lot more energy in each particle. To effectively block that would take a shield with energy 100x greater. If Bamford's shield ...

18

This answers the question on how to block ions coming directly from the Sun from hitting Mars by a satellite stationed at L1. It does not cover the fact whether such a shield is effective in reducing the radiation level on Mars surface. See e.g. here for more details on radiation. First, let's have a look at the magnetic field needed. Inside a magnetic ...

16

It is not coincidence and it does not apply to just the Earth. The Sun, Earth, Jupiter, Saturn, Uranus, and Neptune all have sizable magnetic fields. Mercury and Ganymede have smaller but still noticeable magnetic fields. All of these bodies have one thing in common: They have a sizable amount of rotating, electrically conductive fluid somewhere beneath the ...

15

NTRS to the rescue: Alternating Magnetic Field Forces for Satellite Formation Flying (2012) http://hdl.handle.net/2060/20120015763 Youngquist, Robert C.; Nurge, Mark A.; Starr, Stanley O. Selected future space missions, such as large aperture telescopes and multi-component interferometers, will require the precise positioning of a number of isolated ...

13

Given the question, as written (rather than the misleading title) - yes, a magnetic accelerator could be used to launch a spacecraft. The issues with so doing are several. the contents of the craft need to survive the magnetic fields needed for reasonable length accelerators the track the linear track is extremely long the circular track causes fairly ...

13

A set of three orthogonally aligned torque rods wired up so they can generate a magnetic dipole field of either sign (i.e. flip the North and South poles) can generate a magnetic field of arbitrary orientation (up to the maximum vector sum of the dipole moment of each rod individually). This artificial field interacts with the Earth's magnetic field to ...

13

Check with Kentucky Space. They have KySat-2 on orbit using passive magnetic control. Here is a description of the control system from their website: Passive Magnetic Stabilization: KySat-2 is equipped with a passive attitude control scheme known as Passive Magnetic Stabilization. This passive control technique uses permanent magnets and magnetic ...

11

In theory, yes, if the accelerator and the spacecraft are of the same mass, they'll gain the same amount of velocity when they pass, and so they'll meet at a higher altitude on the opposite side. If they aren't the same mass, then the lighter one gains more speed than the heavier, and they won't meet up again. In practice, I don't think it's workable. The ...

10

First of all, it is a bit odd to talk about specific plans. If you think about emergency procedures for other natural phenomena, such as Hurricanes or Earth quakes, you need to keep in mind that a reversal is a long-term process which is supposed to take decades to centuries. This is what is called geological time scales. In a way, some scientist say, that ...

10

According to Wikipedia on formal definition of the dynamo theory, which itself paraphrases The Earth as a Distant Planet, Vázquez et al.: There are three requisites for a dynamo to operate: An electrically conductive fluid medium Kinetic energy provided by planetary rotation An internal energy source to drive convective motions within the ...

10

Yes, this is purely speculation (+: (apart from the content available from web-references) Wikipedia writes to say Mars is the fourth planet from the Sun and the second smallest planet in the Solar System. Named after the Roman god of war, it is often described as the "Red Planet" because the iron oxide prevalent on its surface gives it a reddish ...

10

RAX and RAX-2 and possibly other cubesats launched by the University of Michigan (I can't remember at the moment) used fixed neodymium based magnets on their Z+ axis. Hysteresis was added to dump any residual momentum after P-Pod ejection. On the RAX missions, the magnets then were used to orient the satellite vertically over the poles where the science ...

9

There are several misconceptions in your question/proposal: The Orion and the Dragon as well as other reentry capsules do not fly with the cone tip forward. They fly with the blunt "bottom" side forward. (fixed in the revised question) Plasma is created by the very passage of the vehicle through the air at high hypersonic velocities. At lower velocities, ...

9

No, accelerometers do not rely on the magnetic field of the Earth. Diagrammatic explanation of how inertia is used to measure acceleration. (Source) As detailed here (own highlighting): Conceptually, an accelerometer behaves as a damped mass on a spring. When the accelerometer experiences an acceleration, the mass is displaced to the point that the ...

9

If you are able to terraform Mars in some reasonable amount of time, let's say in 100 years, then you don't need a magnetic field. Just do whatever you did to terraform the planet, but at one billionth of that rate, in order to counter the loss of atmosphere to the solar wind. Or don't even bother at all, leaving the problem to your great1000000-...

9

It's a "beam core" engine, described in some further detail on Project Rho's Big List O' Engines: Microscopic amounts of antimatter are reacted with equal amounts of matter. Remember: unless you are using only electron-positron antimatter annihilation, mixing matter and antimatter does NOT turn them into pure energy. Instead you get some energy, some ...

8

Using gravity to remotely look at the hidden interior of a planet or moon has a remarkably long history. The idea goes back to Newton. He suggested measuring the divergence of a plumb bob near a mountain from the surveyed normal as a means of assessing the mass of the Earth. He dismissed this idea as impractical given the low quality of surveying ...

8

Earth's atmosphere is also slowly "leaking" into space, but very slowly. This is because there are multiple processes involved in escaping atmospheres. One of those processes is Jeans escape, where due to Maxwell speed distribution and long enough mean free path molecules are able reach escape velocity and escape the atmosphere before "bumping" into another ...

8

This question assumes Mars doesn't have a magnetic field because Mars' core is frozen solid. It's not. Mars has a partially liquid core, just as does the Earth. (The Earth has a liquid outer core and a solid inner core.) Whether Mars has a solid inner core is unknown, but it certainly does have a liquid outer core (and possibly a fully liquid core). (See C.F....

8

This turns out to be a pre-space-age thing. It's not really needed, most of the time it's perfectly fine to float around. On Skylab they provided an elaborate system of triangular grid floors and special shoes with triangular cleats to lock into them. The crew hated them and hardly ever used them. When body positioning is important (like for flying the ...

8

Yes, actually, and it is commonly used for LEO satellites. I know of a number of satellites that use magnetic field information to determine their location. It won't provide absolute attitude, but it is sufficient that another point of reference, such as the Earth's curvature or sun's position, is sufficient to determine where the spacecraft is pointed. It ...

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