what is solar wind?

[isabeau]

yesterday i was talking to someone.. and they mentioned to me that rocket ships can be made to go ten times faster in space with the aid of solar wind.. what is that? is it wind from the sun? i thought there was no wind in outer space..

isabeau

please forgive the stupidity of this question, but i honestly would like to know what it is.. thanks

 

[milagros317]

Wind on earth is moving air, which mostly (about 80%) consists of nitrogen gas. The particles that are moving are entire molecules, which have netural net electric charge.

In contrast, the solar wind is streams of charged particles (mostly electrons and protons) ejected by the sun and streaming out from it in all directions.

Further description here:

http://science.nasa.gov/ssl/pad/solar/sun_wind.htm

 

[isabeau]

thanks mils....

isabeau

 

[maniactickler]

Not sure about that type of wind. my specialty is in the field of breaking wind.

 

[Strider]

I was wondering when you'd notice there was a thread with 'wind' in the title

 

[isabeau]

I was wondering when you'd notice there was a thread with 'wind' in the title

isabeau

 

[kered]

Not sure about that type of wind. my specialty is in the field of breaking wind.

You are thinking of legumic wind brought on by baked beans, broccoli, and beer. 😛

 

[kurchatovium]

Well in the way when the Earth gets bombraded with tons of solar particles when the sun has a solar flare it is kind of a "Solar Fart". 😀 😛

 

[General Zod]

Not sure about that type of wind. my specialty is in the field of breaking wind.

God help us if you ever get solar wind

 

[Mastertank1]

Clarification, Izzy;

While the person who told you a rocket using a 'solar sail' to catch the solar wind is able to go ten times as fast as a pure chemical rocket is technically correct, they seem not to have mentioned the drawback that makes it impractical in the real world.
The acceleration any vessel can get from the solar wind is very, very small. It would take months or years for a pure solar sail vessel to reach the speed a chemical rocket attains in seconds. The solar sail vessel can eventually reach a higher top speed because it can keep accelerating for a much longer time, while the chemical rocket can only use half of it's onboard fuel supply to accellerat; it has to reserve the other half to decelerate unless it's intended to never stop anywhere. Even in that case the acceleration stops when the fuel runs out. With the solar sail, the 'fuel' and 'reaction mass' come from the sun (or any other star) and so never entirely run out, although the force does decrease as the distance from the stellar source increases.
In fact, ten times the speed is an understatement. In theory, a solar sail vessel could get up to an appreciable fraction ( say seven or eight tenths) of the speed of light. Fast enough to cause a time dilation effect, so that a person in such a vessel would experience only say three or four months of duration while an observer not on the vessel would live through a year, making the speed of the vessel seem even greater to a passenger on it.

Mastertank1

We who play and dance are thought mad by they who hear no music.

 

[Goodieluver]

If i can hijack for a second

i have asked physics profs at here and at penn state this question

acceleration is dependant on the force exerted and the force thats resisting.

Now in a complete vaccume with no outside forces acting on it, if a ship was using say 10% thrust, would it in theory reach light speed because there are no forces acting on it to slow it down other than fuel consumption?

 

[Icycle]

acceleration is dependant on the force exerted and the force thats resisting.

Now in a complete vaccume with no outside forces acting on it, if a ship was using say 10% thrust, would it in theory reach light speed because there are no forces acting on it to slow it down other than fuel consumption?

Things get a little weird when you get close to the speed of light. As an object with non-zero mass approaches the speed of light, relativistic effects cause its mass to increase, which means you would need an ever increasing amount of force to achieve the same acceleration. The effect is that a object of non-zero mass would require infinite energy to reach the speed of light.

 

[Redmage]

i have asked physics profs at here and at penn state this question

acceleration is dependant on the force exerted and the force thats resisting.

That's what you get for asking a physics professor something. The answer you get is likely to be technically accurate, but may assume or take for granted factors that you aren't informed of. Or the scientist may have needed information that you didn't know he needed in order to give you the answer you were actually seeking.

Very literal-minded creatures, scientists. 😉

What the professor told you is true as far as it goes. Acceleration is dependent on two things: the NET forces acting on an object (such as thrust, gravity, and friction), and the MASS of the object. In mathematical terms,

Acceleration = Force/Mass

Now in a complete vaccume with no outside forces acting on it, if a ship was using say 10% thrust, would it in theory reach light speed because there are no forces acting on it to slow it down other than fuel consumption?

Theoretically, no. As Icycle noted, an object's mass increases as it accelerates. At most speeds humans deal with, this effect is so small that it's almost unmeasurable. But as you approach the speed of light it becomes very significant. Looking at the equation above you can see that a larger mass requires a larger force to maintain the same acceleration. As velocity approaches the speed of light, the object's mass approaches infinity, and therefore the force required to keep it accelerating likewise approaches infinity.

This is why it's not even theoretically possible for any object with mass to reach the speed of light.

But there are other problems with the solar sail. First, you never have a situation in which there are no outside forces acting on an object. Even in the vacuum of space gravity is a consideration. The solar wind pushes objects away from the sun, but the sun's gravity pulls them back, reducing the net acceleration available. In addition, the solar wind itself becomes weaker and weaker as you move away from the sun. If you double your distance from the sun the force of the solar wind is reduced to 1/4 of what it was originally. This means less and less accelerating force as you move out from the earth's orbit.

Solar sails aren't completely useless. Their big advantage is that they allow a spacecraft to be built with no mass (or very little mass) wasted on propulsion systems: fuel, rocket engines, and all the infrastructure needed to feed the one to the other. If you look at the tiny payloads perched atop huge rocket boosters in the space program, you can see that this is no small thing. But they probably won't be the answer to interstellar flight.

 

[Goodieluver]

That's what you get for asking a physics professor something. The answer you get is likely to be technically accurate, but may assume or take for granted factors that you aren't informed of. Or the scientist may have needed information that you didn't know he needed in order to give you the answer you were actually seeking.

Very literal-minded creatures, scientists. 😉

What the professor told you is true as far as it goes. Acceleration is dependent on two things: the NET forces acting on an object (such as thrust, gravity, and friction), and the MASS of the object. In mathematical terms,

Acceleration = Force/Mass

Theoretically, no. As Icycle noted, an object's mass increases as it accelerates. At most speeds humans deal with, this effect is so small that it's almost unmeasurable. But as you approach the speed of light it becomes very significant. Looking at the equation above you can see that a larger mass requires a larger force to maintain the same acceleration. As velocity approaches the speed of light, the object's mass approaches infinity, and therefore the force required to keep it accelerating likewise approaches infinity.

This is why it's not even theoretically possible for any object with mass to reach the speed of light.

But there are other problems with the solar sail. First, you never have a situation in which there are no outside forces acting on an object. Even in the vacuum of space gravity is a consideration. The solar wind pushes objects away from the sun, but the sun's gravity pulls them back, reducing the net acceleration available. In addition, the solar wind itself becomes weaker and weaker as you move away from the sun. If you double your distance from the sun the force of the solar wind is reduced to 1/4 of what it was originally. This means less and less accelerating force as you move out from the earth's orbit.

Solar sails aren't completely useless. Their big advantage is that they allow a spacecraft to be built with no mass (or very little mass) wasted on propulsion systems: fuel, rocket engines, and all the infrastructure needed to feed the one to the other. If you look at the tiny payloads perched atop huge rocket boosters in the space program, you can see that this is no small thing. But they probably won't be the answer to interstellar flight.

Actually, they told me they didnt know

But my concept is, in a perfect vacume with no forces acting on it, what would be there to slow it down. With no drag or gravity acting on the force, what would prevent it from reaching light speed

 

[Icycle]

But my concept is, in a perfect vacume with no forces acting on it, what would be there to slow it down. With no drag or gravity acting on the force, what would prevent it from reaching light speed

Einstein's Theory of Relativity. The faster an object goes, the more massive it becomes. The more mass it has, the more energy is required to accelerate it at the same rate. Even in a perfect vacuum with no other gravitational forces, your theoretical accelerating mass could never reach the speed of light.

 

[Redmage]

Actually, they told me they didnt know

Um, OK. It looked as though you said they told you that "acceleration is dependant on the force exerted and the force thats resisting." That's what you wrote, anyway. Is that not what you meant?

But my concept is, in a perfect vacume with no forces acting on it, what would be there to slow it down. With no drag or gravity acting on the force, what would prevent it from reaching light speed

And Icycle and I answered that question:

a) The faster an object goes, the greater its mass becomes. The greater the mass, the more force you need to keep accelerating. As the velocity approaches the speed of light the mass approaches infinity, and therefore the force needed to accelerate it approaches infinity. This means that you need an infinite force to accelerate an object to the speed of light, and since there is no infinite force this is impossible.

b) Even if it were theoretically possible to find an infinite force, your hypothetical situation of no other forces acting on the craft doesn't exist anywhere in the universe.

 

[isabeau]

thanks everyone for your great answers.. it has helped enlighten me as to what solar wind really is referring. grr i'm trying so hard not to end sentences in prepositions..

isabeau

 

[Icycle]

thanks everyone for your great answers.. it has helped enlighten me as to what solar wind really is referring. grr i'm trying so hard not to end sentences in prepositions..

Don't worry about it. There's nothing wrong with ending a sentence with a preposition. For example, which of these sentences sounds correct to you?

"I don't know where she is coming from."

"I don't know from where she is coming."

I'd be willing to be that the first one sounds normal and natural, but the second one sounds stilted and strange. For this rule, I'd say ignore the prescriptive grammarians, and trust your own ear for what sounds right.

 

[isabeau]

Don't worry about it. There's nothing wrong with ending a sentence with a preposition. For example, which of these sentences sounds correct to you?

"I don't know where she is coming from."

"I don't know from where she is coming."

I'd be willing to be that the first one sounds normal and natural, but the second one sounds stilted and strange. For this rule, I'd say ignore the prescriptive grammarians, and trust your own ear for what sounds right.

thanks...... its like that time someone said... where you all from? and the person responded, i'm from where they don't end their sentences in a preposition.... so the first person then retorts... ok, where you all from, bitch? hehe

and the first sentence makes more sense to me

isabeau

 

[venray]

Solar Wind.........

 

[isabeau]

Solar Wind.........

'
thank you venray... thats a keeper. now i understand how come a rocket ship can move ten times faster.. just stand behind cartman while he lets one rip..

isabeau

 

[vro]

Star farts

 

[BlasterMaster]

Literally charged particles ejected by our solar system's sun at high velocities!

If it wasn't for our planet's magnetic field, the solar winds from Sol would have rendered our planet uninhabitable.

 

[lostphilosopher]

And just like a sailboat using wind on Earth to travel over the oceans, solar wind can be captured by a "solar sail" on a spacecraft to travel through the vastness of space. Though it seems like something from the realm of science fiction, we've actually built and tested unmanned vehicles that do this!

 

[BlasterMaster]

Yup, there's even a really cool old school Japanese anime about a vessel like that.

Though I'm not really sure how practical it would be for interstellar travel from one star system to the other.