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Thyla
2005-Feb-04, 07:36 PM
My brother claims that sunspots can send off flares and 'fry' us, as he puts it. This is kind of scary. I'm not the most knowledgable person when it comes to these things. I thought maybe some of you experts could tell me what these big spots mean and what they could do to us. I've gone years and years without knowing of their existence, and all of a sudden I'm being bombarded by people talking about space storms and protons, and death rays basically.

Would someone be so kind as to educate me in layman's speak about what happens when earth is hit by a big solar flare? I have two kids and I'm getting kind of depressed about our possible imminent incineration. :(

Thanks,
Thyla

Raptor1967
2005-Feb-04, 07:45 PM
I don't think it is anything you need to be worried about. The earths Magnetic field protects us from most of it. Besides its been happening all the time without you realizing it so why worry now. If possible enjoy the light show. The aurora borealis (Hope I spelled that right) is a prime example of the beauty that comes from these solar storms.

I am no expert but I can assure you that is nothing to worry about.

Swift
2005-Feb-04, 07:47 PM
This (http://www.sec.noaa.gov/info/FAQ.html) is a really good question and answer page from the Space Environment Center of the National Weather Service. For example:

3. What is a solar flare?
Though scientists are not sure of what causes solar flares, they do know that they are bursts of electromagnetic radiation. These bursts, which appear in an 11-year cycle, produce radio waves which penetrate the Earth's atmosphere, often disrupting radio transmissions on Earth.
and

22. What types of industries might be impacted by space weather and how?
The communications industry has lots of problems with solar events. Solar activity can garble radio transmissions, fry the electronics on satellites and in antennas. The power industry has problems with solar events as well, as their transformers can be overloaded. Almost any industry that uses electronics in space can be affected by extremely powerful bursts, but these are rare.
Bottom line is that solar flares have been happening for billions of years and unless you have a communications satellite in orbit, you will probably not even notice they are going on.

Thumper
2005-Feb-04, 07:49 PM
I wouldn't worry about getting fried by a death ray anytime soon. Any second now, though, someone much more knowledgable than myself will give you a better explanation, but while I'm here....Our atmosphere and magnetic field do a wonderful job of procecting us from nasty stuff in space. Sunspot and flare activity do sometimes lead to coronal mass ejections (CME's) which is just a fancy way of saying particles from the sun getting flung outward. Occassionally these ejections head in the direction of Earth. Sometimes these strong ejections can damage communications sattelites and overload power grids temporarily. But they can also trigger beautiful auroras.

edit: Darn it, tried to spell check "auroras" and got ToSeeked.

Thyla
2005-Feb-04, 08:03 PM
I live in Canada, and I have to admit the borealis are beautiful.

So these flares can't 'damage' the magnetic field though right?

skrap1r0n
2005-Feb-04, 08:12 PM
You know whats an even scarier thought?

Think about all the radiation BESIDES the visible spectrum that is frying the eyeballs of everyone looking through a telescope...

Thyla
2005-Feb-04, 08:17 PM
I'll make a point not to look through any telescopes.

8-[

Raptor1967
2005-Feb-04, 08:21 PM
Unless you have it pointed at the sun and why you would do that anyway I dunno, I dont think that you have anything to worry about when looking through a scope.

Wally
2005-Feb-04, 08:33 PM
I live in Canada, and I have to admit the borealis are beautiful.

So these flares can't 'damage' the magnetic field though right?

Nope! Our magnetic field isn't something that can be depleted. It's constant presence is the result of the Earth having a spinning "liquid" core of molten iron (among other metals). It's not like there's only so much of it, and when it gone, it's gone! It'll always be there!

Nergal
2005-Feb-04, 08:44 PM
My brother claims that sunspots can send off flares and 'fry' us, as he puts it. This is kind of scary. I'm not the most knowledgable person when it comes to these things. I thought maybe some of you experts could tell me what these big spots mean and what they could do to us. I've gone years and years without knowing of their existence, and all of a sudden I'm being arded by people talking about space storms and protons, and rays basically.

Your brother saw a show on the Discovery channel didn't he? I think it was called "Space Storms" or something like that.

That show made some statement about super-massive CMEs (Coronal Mass Ejections) having potentially consequences for life on Earth. What they barely bothered to mention (and then only in passing) was that a CME that big would be not only be much larger than any we've ever observed, but larger that any we theorize as possible.

Bottom line: nothing to worry about.

Hopefully some of the astrophysicists here can flesh that out some more(since we've just exhausted about all my knowlledge on the subject :D ).

Hamlet
2005-Feb-04, 08:52 PM
You may want to have a look at Space Weather (http://www.spaceweather.com/) for some real-time information about what's happening on the Sun. Check out the links at the bottom of the page. There's some good info to be had.

If you want to delve a little deeper into the subject, have a look at the Solar Physics (http://science.msfc.nasa.gov/ssl/pad/solar/default.htm) page.

The bottom line is that solar flares are not going to "fry" us. The Sun has been doing its flare and CME thing since before there were humans to worry about it. We're fairly well protected by our atmosphere and magnetic field. Enjoy the light show! :D

JohnD
2005-Feb-04, 09:08 PM
All,
Here in the UK, at Latitude 54, aurorae are unusual, but about two weeks ago there was a wonderful display, that I MISSED! An astronomical friend didn't , showed me his photos and explained about the massive sunspot and a mass ejection from it. I learnt from the Space Weather link above that this was Sunspot 720, now on the Sun's farside but still going strong. So can I hope for another auroral display in two weeks time? About the 17th?

John

Thyla
2005-Feb-04, 09:24 PM
I'm looking at all the links you provided now. I feel SO much better. Thanks!

T.

JustAGuy
2005-Feb-04, 09:43 PM
I'm looking at all the links you provided now. I feel SO much better. Thanks!

T.
In addition to the information and pictures on those pages, the next time a large sun spot comes around, you can easily see it for yourself! Simple solar projectors are pretty easy and quick to construct, and give surprisingly good views of very large sunspots.

You can google for "safe solar projection" for more info, but here's one example of many results:
http://www.eclipse-chasers.com/safe.htm

In the past, I have also used a small set of binoculars to project a solar image onto my white wall for viewing. I find this is a bit finicky but worth the effort. (don't look through the binoculars, just look at the image on the wall)

Standard disclaimer: Never, ever, look directly at the sun, as doing so can permanently (and quickly!) damage your eyes, leading to blindness.

Thyla
2005-Feb-04, 09:51 PM
i read somewhere that if you stack lots of photo negatives together and look through them at the sun, that's safe. would you recommend that?

Manchurian Taikonaut
2005-Feb-04, 09:57 PM
i read somewhere that if you stack lots of photo negatives together and look through them at the sun, that's safe. would you recommend that?

No, do not use that method because it could damage your eyes and cause blindness. Project an image of the Sun onto a page, or buy Solar filters from some Astronomy shop..its the safest way

As for the Sun, on Earth everything is fine just like other posters have explained, however people in Space have to worry about it a lot. If you were on Mars or the Moon and the Sun suddenly went violent, its likely that you would face great danger.

Maddad
2005-Feb-04, 10:51 PM
My brother claims that sunspots can send off flares and 'fry' us, as he puts it. This is kind of scary.Thyla
Remember that sunspots are cooler regions of the sun's surface, not hotter regions.

Both the atmosphere and the Earth's magnetic field give you protection from the sun. If you're going to sun yourself at the beach, wear some sunblock and relax.

skrap1r0n
2005-Feb-04, 11:27 PM
I'll make a point not to look through any telescopes.

8-[

I was kidding about that. No worries, keep looking up.

§rv
2005-Feb-05, 01:43 AM
I was looking at a show on National Geographic recently where they talked about how the earth's field flips ever so often and currently it seems to be starting to flip again. One of the theories presented about the source of the magnetism is that there are radioactive elements, uranium and plutonium, in the core which react. Are there any other theories?

Kaptain K
2005-Feb-06, 05:20 AM
Radioactive decay has nothing to do with the Earth's magnetic field, except that it helps keep the outer core molten. Eddy currents in the outer core are the source of the magnetic field. mars doesn't have a magnetic field because its core has cooled and solidified. Venus doesn't have a magnetic field because it rotates too slowly.

Evan
2005-Feb-06, 06:05 AM
i read somewhere that if you stack lots of photo negatives together and look through them at the sun, that's safe. would you recommend that?

NO!. This was actually a safe method of observing the sun PROVIDED THE NEGATIVES WERE FROM PLAIN OLD BLACK AND WHITE SILVER HALIDE FILM. Color film negatives, exposed, while appearing black are actually an excellent infrared bandpass filter. A strip of color negative film while appearing black in visible light is actually about 95% transparent to infrared. If you were to use this to view the sun it would provide a comfortably dark image while your corneal fluid begins to resemble a fried egg white.

Taibak
2005-Feb-06, 04:20 PM
i read somewhere that if you stack lots of photo negatives together and look through them at the sun, that's safe. would you recommend that?

I have to agree with the others on this one. Photo negatives are a BAD idea. Your best bet would be to use either a telescope or binoculers to project an image of the Sun onto something. Be careful though - I have seen cheap telescope lenses melt while doing this.

You might also want to look at buying a pair of solar viewing glasses. A pair shouldn't cost you more than $1 or $2 but will keep your eyes safe. I'll try to find out what brand we used at camp this summer but I'm not having any luck at the moment. If you want to spend more, you could just buy the material used in them - do a Google search for 'solar filters' and you should come up with plenty of hits. Baader Solar film works pretty well. If you really want a dedicated Solar telescope, there's the Sunspotter, produced by Learning Technologies. I use it a lot for teaching, but where it's over $300 it's probably not worth buying for casual use. Lastly, you might want to consider getting a welding filter. If you do, make sure you get AT LEAST #14 glass. Anything less won't provide enough protection.

Kristophe
2005-Feb-06, 05:15 PM
Projecting the sun is very, very easy to do. It's less convenient than looking at it through a solar filter, but you can project rather large images. I do it all the time with a travel telescope that I own. I recommend it over using filters simply because you can see more detail.

Taibak
2005-Feb-06, 07:14 PM
Okay, double checked with my partner from last summer and we used the Thousand Oaks Optical glasses. They worked well.

Russ
2005-Feb-06, 07:24 PM
If you get a welders glass filter be sure it is #14 for electric arc welding. If you get one for gas welding, it will not provide enough attenuation in the correct light freq.'s This is VERY IMPORTANT!

Evan
2005-Feb-06, 08:10 PM
These (http://www.buytelescopes.com/product.asp?pid=5024) are on my next thing to buy list.

Andrew
2005-Feb-06, 09:00 PM
These (http://www.buytelescopes.com/product.asp?pid=5024) are on my next thing to buy list.
Is it safe?

indie85
2005-Feb-06, 10:24 PM
People always say that, never look at the sun; you'll go blind! Well i do, obviously just glances and im not blind yet, infact i can safely say my vision is just as good as ever. Obviously staring at it isnt a good idea, but then you wouldnt: it hurts. And quite frankly no ones gonna be looking at the sun directly with binoculars, telescopes. Common sense here people

Thyla
2005-Feb-06, 11:40 PM
it was really sunny here today and i tried to look at the sun, for a moment, it was pretty durn bright though lol.

does anyone know what was the biggest CME ever recorded? was it the one in the nineteenth century? i find this all so interesting.

expirationdate
2005-Feb-06, 11:44 PM
I'm getting kind of depressed about our possible imminent incineration. :(

Thanks,
Thyla

Thyla, not to inthuse your depression more but "we", (all of human kind) could be wiped out by alot of things space has to offer at any given second. Worrying about solar flares are yah? Well, don't worry too much becuase our atmosphere protects us a great deal from being (fried) as your brother put it, that is of course assuming you're not in a space suit floating somewhere in space where it does the most damage. And for those sunspots, they actually appear darker becuase they are cooler areas on the sun and which are still white hot, they happen to look darker becuase the area around them is hotter.

Quantum_Raider
2005-Feb-07, 12:10 AM
does anyone know what was the biggest CME ever recorded? was it the one in the nineteenth century? i find this all so interesting.

It looks like the largest was on September 1st, 1859 - Solar Superstorm (http://www.firstscience.com/SITE/ARTICLES/superstorm.asp)

Apparently the Aurora Borealis appeared as far south as Cuba and Hawaii
:o

Taibak
2005-Feb-07, 05:58 AM
People always say that, never look at the sun; you'll go blind! Well i do, obviously just glances and im not blind yet, infact i can safely say my vision is just as good as ever. Obviously staring at it isnt a good idea, but then you wouldnt: it hurts. And quite frankly no ones gonna be looking at the sun directly with binoculars, telescopes. Common sense here people

True, but Wise Man once say, 'Common sense is neither common nor does it make very much sense.' You'd be amazed how many people out there think that it's more dangerous to look at the Sun when it's eclipsed than when it isn't. I'm sure that a few of my camp kids, despite being gifted students, would be stupid enough to try looking at the Sun through an unfiltered telescope. As for glancing at the Sun with your eye though, I really don't reccomend doing it at all. Yes, you can do it for a short amount of time without causing much damage, but repeated exposure isn't going to do you any favors. It's really better not to chance it.

You bring up a good point though. If you find yourself looking at the Sun, through a filter or otherwise, and it hurts, STOP. You could have a scratch or a hole in the filter or you could be getting excessive amounts of heat in your eye. Both are bad.

Kaptain K
2005-Feb-07, 08:37 AM
The retina has no pain nerves. Neither do the lens nor the cornea. If you feel pain, it's [b]way[/b ]too late! Better safe than sorry!

indie85
2005-Feb-07, 02:05 PM
The retina has no pain nerves. Neither do the lens nor the cornea. If you feel pain, it's [b]way[/b ]too late! Better safe than sorry!

We all know its not pain in the typical sense Kaptain, its just instinctive to look away from it after a milisecond or two. It hurts in the same way you turn on the lights in the middle of the night.

Good points Taibak, I figure most people get bored of glancing at the sun anyway so its never a regular experience. I worked this out as a kid, like most people i imagine, not particularly entertaining experience so you then dont do it. From then on you have that experience as a basis to do it again, so people dont, maybe do it once in every five years say to remind them of that golden ball lol. I guess the only problem would come when events like eclipses come up, when its no longer a dull experience, and i guess a real danger people could stare at it.

um3k
2005-Feb-07, 04:42 PM
Is it safe to look at the sun at sunset, when it's just above the horizon?

Evan
2005-Feb-07, 05:33 PM
Generally it is safe to look at the sun at sunset. It must be since I have many times and my vision is just fine at age 55. Also on rare occasions when the fog is just right you can safely look at the sun through a layer of fog. I have seen sunspots this way with my (almost) naked eyes. Your eyes will notify you right away if it is too bright to safely look at. When doing this I always wear dark sunglasses as they will provide pretty good short duration protection.

The thing that causes the immediate damage when looking at the unfiltered sun is not the ultraviolet but the infrared. Most of the suns energy after passing through the atmosphere is in the infrared part of the spectrum. This is why welders glasses are green. Green is the complement to red and filters infrared efficiently. Certain antireflection coatings on eyeglasses also filter infrared with nearly 100% efficiency.

Long term damage is caused by the ultraviolet portion of the spectrum. This eventually causes yellowing of the lense of the eye and can cause cataracts in cases of severe exposure. I have always worn sunglasses since I was a small child as I have blue eyes. Blue eyes are much more sensitive to light than brown eyes for the same reason that light skin is more susceptible to UV damage than dark skin. I have always wished that I had darker skin so I wouldn't need to take as much care when out in the sun.

When at the Mt. Kobau star party in southern BC it is imperative to take serious precautions to avoid sunburn of both skin and eyes. The top of the mountain is at 6400 feet elevation and the UV is brutal. A wide brim hat and spf50 sunblock are essential.

It isn't a good idea to wear really dark sunglasses. They can do more harm than good if not designed correctly with side shields. Very dark glasses allow the pupil to open more than usual and if bright light comes in from the sides it can cause damage.

If you do sunburn your eyes it is an experience you will not soon forget. I do a lot of metalwork including arc welding. There is a common affliction known as "welders flash" which is a UV burn of the eye from the welding arc if looked at without protection. There is no apparent pain felt at first. Laters, after some hours, your eyes begin to feel as though someone has poured sand in them. There is nothing that can be done to alleviate this feeling other than a bit of relief from anesthetic drops. It lasts for a couple of days and is one of the most irritating experiences you can imagine.