When the Earth's magnetic field flips

[glend (Glen)]

The media carried a story today about the over-due magnetic field flip, and the affects this might on various systems we rely on. It had me wondering about the impacts on astronomy.
I believe that anyone with a permanent pier mount which is properly polar aligned now, would be fine, at least in terms of alignment. After all the Earth itself does not flip, and stars are all in the same place. However, folks using a compass to setup their mount, whether in the backyard or a dark site, could get messed up pretty good. I would imagine it could take a flipped field some time to find equilibrium and settle down, making compasses useless. Polar aligning could still be done, as the stars are still there, but having landmarks to indicate south could be usefull. There is a hill at Bretti dark site which lies at true south, and i know my backyard well enough to have it marked on the fence and the observatory wall.

Now the software that we use to point our scopes would have totally wrong meridian and cardinal point information, and Az references would be screwed up. Would EQ RA and DEC be ok? I think so, as long as you didn't change mount orientation. Am i wrong, and we'd all be buggered?

Are there other affects that would play out for astronomers?

[xelasnave]

Well for a start we would have to adjust to living in the Northern hemisphere.
And ...well I dont think I could.
Alex

[LewisM]

I'd be more concerned about extreme radiation not being stopped by the magnetosphere - enough to fry people/oceans rather than the ramifications for astronomers.

[glend (Glen)]

Originally Posted by LewisM

I'd be more concerned about extreme radiation not being stopped by the magnetosphere - enough to fry people/oceans rather than the ramifications for astronomers.

I believe the field is suppose to remain intact, its just the magnetic poles that move, ie swap polarity. The field should continue to protect earth, maybe a brief period of realignment of the magnetic lines of force. Sure it maybe thinner or thicker here and there as it adjusts itself. Of course no one knows for sure until it happens but there was complex life on Earth the last time it happened.

Here is the link to the scare mongering media story:

http://www.news.com.au/technology/sc...9c52bcd14734c9

[AndyG (Andy)]

I remember seeing this on the ABC TV show Quantum, in the late 80's. They showed a world map with normal poles, then lots of little "N"s & "S"s everywhere, then "N" over Antarctica.

I wonder how sure they were of it then? I personally believe this is going to be a problem for our great great grandchildren (or add another "great", if you're chronologically advanced*). My biggest regret is being totally helplessness to assist them today.

OK folks. Place your bets on what will happen, and get the Mods to make it a sticky. in 2000 years, the 4018 "Internet Wayback Machine" can decide a winner!

*Note, I didn't use the term "old", which is disengenious, based on wisdom from a recent thread here.

[xelasnave]

Andy you have more future than most don't waste it.
Stay positive and keep the future positive.
Alex

[AndrewJ]

I remember seeing a doco on this ( and how they were working out the timings ) a few years back
There is a large crack in the mid atlantic that is increasing in size and has been for a long time. By studying the polarity of the volcanic residue that came up, as you move away from thre crack, you can see what has happened.
https://www.geolsoc.org.uk/Plate-Tec...Atlantic-Ridge
No idea how quick the flip is tho.

Andrew

[baileys2611 (Simon Bailey)]

Originally Posted by xelasnave

Well for a start we would have to adjust to living in the Northern hemisphere.
And ...well I dont think I could.
Alex

Haaaha! Good one.

Actually magnetic 'flips' are pretty quick because essentially you cannot have two Norths or Souths in a magnet unless you have something made from monopole atoms...which we haven't seen any physical evidence for yet. So a 'flip' in a normal magnet is just that. South one second, North immediately afterwards. But, the earth is more complex than a normal magnet.

Where the problem arises with magnetic location is when the poles 'shift' over time. There's a tipping point when they will flip (which I read recently is unknown) but that can result in multiple Norths and Souths at the same time, over areas of different density, then flip and then shift and then flip again multiple times over a long time (1000 - 5000 years) before it settles down. Basically complete magnetic chaos over a period, then settling down again.

Geologically speaking, that's pretty much instantly, but for us short lived humans it will wreak havoc with navigation and anything that relies on direction achieved through magnetic means.

There's some evidence that the strength of the magnetic field moves around the earth under normal circumstances and while that happens, so there may be some aurora's happening in places that did not have them before, but the protection given to us by the magnetic field won't fall to anything significant enough (maybe up to 5% of normal in some areas) to boil oceans or fry birds. It may have implications for space weather and satellites.

[baileys2611 (Simon Bailey)]

Oh, I forgot to post some sources:

NASA
IFLscience.com
Wikipedia

[skysurfer]

This won't happen instantaneously, but take thousands of years.
Otherwise, 2012 movie (Ronald Emmerich) scenarios appear ....