Team Discovers "Throttle" For Solar Wind

ScienceDaily is reporting that a team of scientists have discovered that Helium may act as a "throttle" for the solar wind. The team hopes that this insight will provide them a better look inside the dynamics of space weather. "Because helium nearly vanishes from the solar wind at its minimum speed, the researchers believe helium might somehow set the minimum speed. Helium is not accelerated efficiently by any process thought to be propelling the solar wind. Instead, it has to be dragged along by the hydrogen: Solar wind hydrogen atoms exert a small electric field that drags the helium out along with it, according to the team."

Curiously...

[packetmon (977047)]

I wonder *how* one measures anything going that slow considering there isn't something *tangible* to watch and measure... I wish the article could have explained this as I am now lost wondering... Which is faster, a slug, three toed sloth, helium or plasma...

Re:

[ThosLives (686517)]

260 km/s isn't very slow in my book.

What's really goofy is TFA says that "lack of helium is what makes it slow" where it really seems like "slow wind isn't enough to pull any helium with it" - I think they have their causal relationship backwards.

Re:

[FuzzyDaddy (584528)]

I think they don't know what's causing what. But there is a minimum speed - below which you don't see solar wind. At this speed, the He concentration also drops to zero. So the two are linked, but from TFA, they don't have a clue as to how.

I think I got that right, anyway. If not, feel free to make fun of me.

The relevant quote...

[FuzzyDaddy (584528)]

"At the minimum speed--the speed where the solar wind is no longer able to drag out helium--the solar wind itself can't escape either," said Dr. Keith Ogilvie.

Anyone else

[morgan_greywolf (835522)]

Anyone else feel like releasing a few million helium balloons right above Redmond, Washington, right about now? ;)

Re:Anyone else

[ScentCone (795499)]

Anyone else feel like releasing a few million helium balloons right above Redmond, Washington, right about now?

Only on slashdot would someone stretch that hard to turn an astrophysics summary into an MS bashing troll. I mean, it takes WORK to do it that cravenly. Whew! You must be tired.

long range satellites

[jshriverWVU (810740)]

Could this be used on long range satellites?

Re:

[jshriverWVU (810740)]

Long range as in ones that leave our system like Voyager vs ones that just float around earth.

Re:

[Moofie (22272)]

I'm not sure I'd consider something on a parabolic or hyperbolic orbit to be a "satellite".

Spacecraft? Absolutely.

Re:

[Goaway (82658)]

As the guy said. Vocabulary issues. "Satellite" does not mean "thingy with antennas floating in space", you know.

Space weather

[Timesprout (579035)]

Alpha quadrant : Freezio!

Beta quadrant : Freezio!

Gamma quadrant : Freezio!

Delta quadrant : Freezio!

no one knows?

[wizardforce (1005805)]

The team discovered that the abundance of helium increased as the solar wind speed increased, from near zero around the minimum speed to more than four helium atoms for every 100 hydrogen atoms at speeds greater than about 500 kilometers per second (310 miles/second).

helium is heavier than hydrogen snd it requires a higher voltage potential to leave the sun's gravity well- in the case of solar wind the concentration of helium is actually lower than in the sun its self [4% vs 25%] the hydrogen has a better chance of escaping and at higher energies helium levels increase.

Re:

[wizardforce (1005805)]

While you're probably right when you say that the cause of the slowing is that the alpha particle is four times heavier than the proton, you are very wrong to bring in voltages. The solar wind is blown out by the pressure gradient, electic potentials have nothing to do with it. And the wind itself is quasi-neutral, meaning that the number of positive and negative charges in a non-infinitesimal volume is approximately equal. Thus an electric field couldn't move this plasmas anyway. And what do you mean when

brake, throttle....

[Himring (646324)]

So, helium is the brake and hydrogen is the gas pedal. Who's driving?

Ok, so, in other words...

[eggstasy (458692)]

Fast wind blows shit around, slow wind not strong enough to do so. Did I miss anything? :|

A clarification

[voislav98 (1004117)]

The Science Daily article gets stuff a bit wrong. The hydrogen mentioned is not hydrogen it's protons (hydrogen without the electron), which are accelareted by the Suns magnetic field. Helium, being a neutral atom, is much less affected by the magnetic field and it moves much slower than the charged protons. Now, charged particles have a very high probability of colliding with a neutral atom (much highr than the neutral atom has), so protons will keep colliding with helium which will slow them down. The ana

Boring Weather

[Hoi Polloi (522990)]

The problem with solar weather is that every day is the same, hot and sunny.

Re:

[Oktober Sunset (838224)]

on a molecular level tho, there can be an induced dipole.

Re:

[by Anonymous Coward]

it's a plasma. without electrons, it's a positive ion.

Re:I don't buy it

[mbike (1108739)]

This is not neutral hydrogen therefore it is highly affected by the electric field. This plasma has come from the sun which is way to hot for molecules or neutral atoms for that matter. The article does make good sense.

Re:

[Lord Lemur (993283)]

Ok, I think everyone is kinda missing what the question and answer are here...

The question is why in the name of the sweet baby Jeebus does the solar wind have a minimum speed of about 161 miles/sec. It sounds like, according to the article that the ammount of helium asomatotically approaches 0 as the speed slows to 161 miles/sec.

So the question becomes:

1) why must helium be present?

2) why is there a relationship since nothing that promotes the solar wind is thought to have an effect on the air speed of an

Re:

[Red Flayer (890720)]

2) why is there a relationship since nothing that promotes the solar wind is thought to have an effect on the air speed of an unladen plasma of helium?

Would that be African, or European, plasma?

Seriously, though, there was a passage in TFA that explains it. As I understahd it, solar wind has an escape velocity necessary to leave the sun; factored into this is the drag created by the He-H attraction (which I'm not too clear on, since they are both positive ions). Since He is heavier, its escape velocity i

Re:

[tnk1 (899206)]

Next thing you know they'll have online creationist universities where you can get your degree in just 10 weeks! Apply now!

Bob Jones University Online?

Re:

[nelsonal (549144)]

In the fine print it says see 2 Peter 3:8.

Re:Helium is a byproduct of wind speed, not cataly

[Zancarius (414244)]

I have to agree with this sentiment. The article seems to have been targeted at a fifth grade reading level (or below) and was quite painful to read. It isn't Science Daily's fault, however, as it appears the article was not an "adaptation" but rather a blatant reprint [mit.edu] of the original press release. Oh, silly me, I forgot one minor detail: Adaptations are little more than a copy and paste away!

The WIND-SWE group appears to have links [mit.edu] to some of the papers they have presented. I'm not sure of the relevancy b