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gokuson123
2008-Feb-01, 12:30 AM
I went to see if TU24dotOrg was down yet, and I'm going to be honest: I love seeing these nuts proven horribly wrong or just collapse under their own idiocy. The amount of energy it takes to rebel against all logic and make certain websites...just astounds me. Of course, the man who I see as the worlds first proof against evolution has risen his "risk" threat meter, claiming our magnetosphere is going nuts.

Now, I know that poor soul can't be saved, but maybe you can educate me. What is all that about? I read somewhere that those fluctuations are normal.

I'm still hung up on that site, I wish someone would remove it. I know NASA posted an article explaining why there is lots of weird weather, but I don't know much about the other stuff.

Edit: Sorry if I sound harsh about that site in particular, but it's not like people haven't tried to educate them. I lose patience for those who choose to be ignorant, and it's not like we have theories, either. We have lots of facts, and I hope to learn some soon.

tusenfem
2008-Feb-01, 09:24 AM
Everything is normal in those movies and pics and whatevers.
They talk about spikes in the magnetic field, but I have no idea where they see them.
They see the lines move in a strange way in the movies, these are magnetic field lines, but that is just the normal behaviour of the magnetotail. The field lines are stretched by the solar wind, and when the solar wind's magnetic field turns southward (i.e. Bz becomes negative) a substrom/reconnection event can be triggered in the tail, which will let the field lines "shoot back to the Earth", like elastic strings that are losend.

I think I explain a little more in the other TU24 magnetosphere thread.

They think that without any physical edumacation they can look at simulations of the solar wind magnetosphere interaction and tok sajens.

Forgeddaboudit

John Mendenhall
2008-Feb-01, 05:40 PM
A link to the site in question, perhaps?

Thanks, John M.

edit: Never mind, there's an explicit link elsewhere in Q&A. Which unfortunately I followed and read.

These guys sit there and watch a 'real-time solar wind simulator'? What did Captain Kirk's Evil Twin say to the Trekkies?

Answer: "Get a life, guys!"

gokuson123
2008-Feb-01, 09:15 PM
Heh yea. I'd believe in flying carpets before what they say, although I'd like to myself know about this issue.

antoniseb
2008-Feb-01, 09:25 PM
Edit: Sorry if I sound harsh about that site in particular, but it's not like people haven't tried to educate them. I lose patience for those who choose to be ignorant, and it's not like we have theories, either. We have lots of facts, and I hope to learn some soon.

Thanks for the post edit. Even though we don't specifically know if the people from that site frequent this forum, we'd prefer for you to express concerns about specific statements of theirs, and not characterize the people in insulting ways.

It is true that they seem to be ignoring a lot of what we take to be facts.
You can speculate as to whether they are deliberately trying to mislead people. We'd really prefer you to not call them fools.

tusenfem
2008-Feb-01, 09:45 PM
I don't know exactly what you would like to know, but be assured that magnetospheric physics is not for the faint of hearts. But I might give an intro here.

The Earth has a magnetic field, generated in the fluid core. Would the Earth stand on its own, this field would be mainly dipolar, which means that it looks like the field of a bar magnet which one sees when putting iron dust near the magnet, but then rotate it around the axis of the magnet, so you get a "spherical" shape with two dips at the poles.

Now, the Earth does not stand alone, but is turning around the sun and the sun sends out the solar wind, a stream of ionized gas (plasma) with a magnetic field embedded. The solar wind has a velocity of 350 to 400 km/s in normal situations and a density of a few particles per cubic centimeter. If you would look on top of the sun earth plane you would see that the magnetic field lines create a spiral, the so called Parker spiral.

Now, the solar wind interaction with the Earth's magnetic field makes that that "spherical" shape gets pushed in at the day side of the Earth, and at the night side the the field lines get pulled along with the solar wind and create a long tail, not unlike what you see in a comet.

You can only stretch field lines so much, even though they are only mathematical entities. If the tail gets too long (in a way of speaking) and something happens that disturbs it, the field lines will get pressed together and in the middle of the tail the field lines are oppositely directed, and then reconection takes place.

This reconnection makes that the field lines get differently connected. Sort of like when you pull taffy, you see it get thinner and then it breaks in the middle. Naturally, it is slightly more complicated, but we will not go into that at the moment. At the "break", the part that is on the Earth side will shoot back to the Earth like an elastic band, and the part at the other side will be taken away by the solar wind.

The part that shoots to the Earth accelerates a lot of plasma and creates the aurora borealis and australis.

What disturbs the tail is variations in the solar wind, and mainly the vertical component of the solar wind. Most of the time this component is northward, but on average several times per day it turns southward and that makes that on the day side of the Earth the magnetic field of the Earth and of the solar wind are oppositely directed and reconnection takes place, this makes that field lines of the Earth are transported with the solar wind towards the tail and those have a impact there, and that can compress the tail so that reconection happens there.

This is a so called substorm, which is a very normal process in the magnetotail, which happens every 4 hours or so.

So, this was a short introduction.

Note that a magnetic storm is not made up out of a lot of substorms although the name substorm might lead you to think that.

gokuson123
2008-Feb-02, 07:50 AM
I don't know exactly what you would like to know, but be assured that magnetospheric physics is not for the faint of hearts. But I might give an intro here.

The Earth has a magnetic field, generated in the fluid core. Would the Earth stand on its own, this field would be mainly dipolar, which means that it looks like the field of a bar magnet which one sees when putting iron dust near the magnet, but then rotate it around the axis of the magnet, so you get a "spherical" shape with two dips at the poles.

Now, the Earth does not stand alone, but is turning around the sun and the sun sends out the solar wind, a stream of ionized gas (plasma) with a magnetic field embedded. The solar wind has a velocity of 350 to 400 km/s in normal situations and a density of a few particles per cubic centimeter. If you would look on top of the sun earth plane you would see that the magnetic field lines create a spiral, the so called Parker spiral.

Now, the solar wind interaction with the Earth's magnetic field makes that that "spherical" shape gets pushed in at the day side of the Earth, and at the night side the the field lines get pulled along with the solar wind and create a long tail, not unlike what you see in a comet.

You can only stretch field lines so much, even though they are only mathematical entities. If the tail gets too long (in a way of speaking) and something happens that disturbs it, the field lines will get pressed together and in the middle of the tail the field lines are oppositely directed, and then reconection takes place.

This reconnection makes that the field lines get differently connected. Sort of like when you pull taffy, you see it get thinner and then it breaks in the middle. Naturally, it is slightly more complicated, but we will not go into that at the moment. At the "break", the part that is on the Earth side will shoot back to the Earth like an elastic band, and the part at the other side will be taken away by the solar wind.

The part that shoots to the Earth accelerates a lot of plasma and creates the aurora borealis and australis.

What disturbs the tail is variations in the solar wind, and mainly the vertical component of the solar wind. Most of the time this component is northward, but on average several times per day it turns southward and that makes that on the day side of the Earth the magnetic field of the Earth and of the solar wind are oppositely directed and reconnection takes place, this makes that field lines of the Earth are transported with the solar wind towards the tail and those have a impact there, and that can compress the tail so that reconection happens there.

This is a so called substorm, which is a very normal process in the magnetotail, which happens every 4 hours or so.

So, this was a short introduction.

Note that a magnetic storm is not made up out of a lot of substorms although the name substorm might lead you to think that.

Thank you, very informative, I understood like 98% of it =)

I remember seeing something on The Science Channel about magnetic fields on the sun being pulled sideways till they snap and send out plasma. Kinda makes sense this field would be varied greatly because of how dynamic it is.

fotobits
2008-Feb-02, 02:34 PM
From tu24.org:

The Midwest Regional News story reports that the advancing cold front today is sending temperatures across the Midwest plummeting by as much as 30 degrees in just a few hours. Meanwhile, a storm along the leading edge of the cold air mass led to an outbreak of blizzard conditions across eastern Iowa.
All I'll say is the site is evidence that our nation's schools are no longer teaching critical thinking skills.

Neverfly
2008-Feb-02, 03:15 PM
Well- he almost has to. After-all, he made a $500 wager with the BA on it.

Gillianren
2008-Feb-02, 06:30 PM
There's a serious cold front across the Midwest? In winter? Clearly, something otherwordly must be responsible!

Van Rijn
2008-Feb-03, 12:15 AM
There's a serious cold front across the Midwest? In winter? Clearly, something otherwordly must be responsible!

Heh. Here's what I said back on the 27th:



Agreed, but one note: From comments I've seen, the TU24 video person is suggesting that 2007 TU24 won't hit Earth, but is saying there will be vague "effects." I fully expect they will operate much like former BAUT member Dutch: They will comb the news after the fact, and find things to fit their expectations. Those might be things like snowstorms in Kansas or small earthquakes in Japan. They'll likely ignore anyone who points out that these things happen with or without asteroids.

(emphasis added) Maybe I should start advertising my amazing predictive abilities. Of course, somebody around here would probably point out it was like shooting fish in the barrel, and I wasn't the only person who made predictions like this, but I'll just ignore them. :lol:

Edit to add:

I forgot that I first wrote about this on the 22nd:


Heh. This is amusing. In comments on BA's blog (http://www.badastronomy.com/bablog/2008/01/21/repeat-after-me-asteroid-2007-tu24-is-no-danger-to-earth/), the TU24 fellow said this:

If there are no effects from asteroids WD5 and TU24 by Feb 1, 2008, such as illustrated in my video, then I will personally donate $500 to support the Bad Astronomy website server or to a charity of your choice.

So, he's talking about "effects," not "impact." ;) I have no doubt he'll latch onto bad weather somewhere, or other natural events that happen somewhere on the planet, every day, and declare these were somehow caused by the asteroid.[snip]

Actually, it's kind of sad just how predictable it is.