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."

Comments

Re:Curiously...

[ThosLives]

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:Summing up the article

[Lord Lemur]

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 unladen plasma of helium?

QTF: /quote

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. /quote

Basically, they don't have a frigg'n clue, but they figured out how the helium might be present.

Re:Curiously...

[FuzzyDaddy]

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.

Re:long range satellites

[Moofie]

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

Spacecraft? Absolutely.