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The Quietest Sun
Posted by
kdawson
on Tue Oct 14, 2008 01:51 AM
from the storms-a-comin' dept.
from the storms-a-comin' dept.
Orbity sends in a Boston Globe report on the unusual calm on the surface of the sun. The photos, many taken in more active solar times, are excellent — see the sequence from last year of a coronal mass ejection carrying away the tail of a comet. "The Sun is now in the quietest phase of its 11-year activity cycle, the solar minimum — in fact, it has been unusually quiet this year — with over 200 days so far with no observed sunspots. The solar wind has also dropped to its lowest levels in 50 years. Scientists are unsure of the significance of this unusual calm..." As if to be contrary, New Scientist mentions that the number of sunspots seem to be increasing.
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the significance of this unusual calm (Score:5, Funny)
The sun is dying. Netcraft confirms it.
oblig (Score:4, Insightful)
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Taking pictures of the sun? (Score:3, Interesting)
Speaking of the sun, I recently bought a DSLR camera, and I would like to take pictures of the sun with it. Does anyone of you know how to go about that without destroying the camera's sensor or my eyes? What kind of filter do I need? Some people suggested a piece of glass that people use for welding; is that good enough?
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Astronomy sun filters. (Score:2, Informative)
Dont people google any more?
Google answers all of you questions just ask, its like the oracle , it sees all, knows all, its your friend. Google just needs a 3d avatar, and a voice of Hal.
Re:Taking pictures of the sun? (Score:5, Interesting)
http://www.baader-planetarium.com/sofifolie/sofi_start_e.htm [baader-planetarium.com]
I have also seen some people use modified telescope filters (Calcium K-line).
Parent
Re: (Score:2)
Sensor:
Your shutter speed will be maxed so the sensor's exposure to the bright focused sun will be minimal anyway, don't worry about it. Shoot it.
Eye:
Liveview. If not available, shoot 100, 1000, 10000, it's digital anyway. Shoot until you find the one you like. I presume you're using some kick ass 500mm, or even better, get a telescope and an adapter.
Happy shooting :D
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Your shutter speed will be maxed so the sensor's exposure to the bright focused sun will be minimal anyway, don't worry about it. Shoot it.
Apart from the other fault pointed out by another poster, you're missing the important fact that not only the imaging sensor is a sensitive component.
The autofocus sensors, the metering sensors, the mirror and *the shutter itself* are all sensitive components. The manual of my Olympus dSLR says not to do it, and I doubt it's in any way unique.
The only responsible advice is to get a filter built for this very purpose before shooting.
Re:Taking pictures of the sun? (Score:5, Informative)
The best way to do it is with a solar telescope, which will get you a nice, zoomed-in shot. Alternatively, you can buy solar filters for telescopes, but you must be absolutely positive that they are high quality and you must have one that covers the main telescope aperture; those that cover only the eyepiece are dangerous as fuck.
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Alternatively, you could simply project the image from the telescope to a piece of paper/cardboard and photograph that. That way there's no chance of filter failure, because there is no filter.
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Well, buy (from e.g. B+W) an ND1000 filter or higher. that should do the trick, and unlike the welding goggles, cannot accidentally come off the lens...
The goggles! They do nothing! (Score:3, Insightful)
You might check with your local 'Astronomy Club', or if a planetarium is nearby, maybe someone there could give you the benefit of their (individual/group) experience.
Even though I have benefited from some real gems at /. , I would still do some independent research for something like this.
Re:Taking pictures of the sun? (Score:5, Informative)
The welder's glass will do at a pinch although it's not really sufficient for prolonged viewing of the sun. You'll also need to figure out some means of fixing it to the camera and you might find that it causes some unusual colour shifts in the image as well. Alternatively, you can get hold of a neutral density filter specifically designed for solar-photography; typically these will equate to about 10-15 stops of light loss - Cokin's NDX is one of the "cheapest" options, but that's relative; these are niche products that can be quite hard to find and are priced accordingly.
As to composing and focusing without damaging the sensor or your eyes... Well, it's a good idea to be quick. :) Assuming you gave a "proper" DSLR with a through the lens viewfinder, then you can use the old trick of holding a piece of card a few inches from the eyepiece for basic composition, and on newer models you can also use the live preview screen function. Be aware though that when using the latter method your sensor will be exposed to the sun, so don't take too long or your sensor may get damaged. Focussing isn't too critical; set the camera to manual focus and focus on infinity before you start, and you should get a perfectly usable result, although for pin sharp shots of sunspots a little more precise focussing may be required. Typically, my approach is as follows:
Be aware that with longer focal lengths the sun will move fairly rapidly across the viewfinder, but unless you are using an insanely long telephoto lens or a telescope with an adapter then this shouldn't be a major problem if you leave room for the sun to move across the frame when you compose.
Good luck, and don't take any chances with your eyes!
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Good luck, and don't take any chances with your eyes!
Now think about what happens to the air/glass/coatings/electronics in your eyepiece/camera CCD/eyeball. Think real hard. Think, think, think.
Please, please, please use a real solar filter over your camera's lens - a real solar filter fro
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Its perfectly safe, but only if you do it at night.
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You don't actually get cancer from staring at the sun. You just go blind. There's a slight difference between the two.
Ahh, the silence (Score:5, Funny)
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Less than one hundred, if they're Russian [wikipedia.org] nukes.
It just sneaks up on you and ... (Score:4, Funny)
... burns you to a crisp... now it's in a calm state... but it's waiting, taunting us with massive flares... during the so called calm period there was that really big flare on 20080929... yikes... crispy... Sol... stay cool...
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Fewer sunspots (Score:5, Funny)
crisis (Score:4, Funny)
People, pray to your favorite deity for more sun spots!
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ooops I misclicked and you got overrated, I wanted give it funny - mea culpa now I have to write to get it removed
Cycle 24 spot seen (Score:3, Informative)
This story is a little late. Since then a cycle 24 spot group has been seen. Even so, solar activity is still rather low, cycle 24 is late. What does it mean? It means we're going to be in for some very cold weather in the near future.
http://wattsupwiththat.com/2008/10/11/significant-cycle-24-sunspot-group-emerges/#more-3635
Re:Cycle 24 spot seen (Score:5, Funny)
cycle 24 is late. What does it mean?
The sun's pregnant, that's what it means.
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If you want to know about solar activity... (Score:4, Interesting)
Have a look at the SIDC [www.sidc.be]. We count sunspots and get payed for it!
The significance? (Score:3, Funny)
Not that significant? (Score:5, Insightful)
As the sun has an 11 year cycle of activity, is it really that significant that this is the least active it's been in 50 years? That would mean that out of the last 5 solar minima this is the quietest, which it doesn't take a physicist to notice is a 1 in 5 chance - hardly breathtaking.
Re:Not that significant? (Score:5, Insightful)
It's even less surprising. If this minimum's activity is lower than the last one, it's automatically "the lowest in the last x!". And if were higher, vice versa.
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Indeed, I can't refrain from commenting on the part of TFS that notes that "Scientists are unsure of the significance of this unusual calm..."
I mean, of course they're not sure. They shouldn't care about the significance of what the heavenly bodies are doing at all. That is the area of astrologers and other pseudo scientists.
Any self respecting scientist should answer the question "What does it mean when the sun is unusually quiet?" with "It means that the sun is unusually quiet."
Who's to blame? (Score:5, Funny)
Come on! We must be able to link this to some kind of human activity!
hmmmm. (Score:5, Insightful)
and
(2) did I not hear that this is linked to the lull in global warming recently, and as soon as the sun picks so does the heat? is this true....?
Re: (Score:3, Interesting)
If you ever have a chance to look through one of these:
http://www.coronadofilters.com/ [coronadofilters.com]
definitely do so. They are extremely expensive telescopes, so unless you're *really* into amateur astronomy and include solar observations as part of your hobby, then they are prohibitively expensive. With that said, these are the first set of telescopes I've looked through where the image at the eyepiece actually matches the pictures you see. In other words, the images at the eyepiece are very close to some of the phot
The quite period is showing signs of ending (Score:5, Informative)
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New spots are beginning to break out on the face of the Sun and may signal the end of a dry spell in solar activity.
For which I, as a radio amateur [calum.org] will be very happy, as we're currently right at the lowest point of the sunspot cycle [wikipedia.org] . The sun's activity correlates with the "reflectivity" of the layers of the atmosphere. When the layers are "reflective", signals can bounce [wikipedia.org], with each bounce landing a thousand or so miles away. If you get a few bounces, you can talk to the other side of the world, even on low power. When there's no propagation [wikipedia.org], you are unlikely to get more than 50 or so miles (groundwave), no matter how m
Very convenient (Score:4, Interesting)
This will give us good readings on how the solar cycle affects this climate.
Sure, Sol might be a pretty quiet Sun... (Score:2, Funny)
.. but the Sparc 1 in my basement is damn silent, I tell you.
Well, we ought to get proof of the sunspot theory. (Score:5, Insightful)
If the lack of sunspots holds on, then, if we get declining global temperatures, then, we might actually be headed into an ice age. Knowing our luck, this would become evident AFTER we've blown ten trillion dollars to lower our CO2.
It's not "degrees K" (Score:3, Informative)
"Kelvins" are units and have been for 40 years. [wikipedia.org]
Re: (Score:2, Funny)
We're doomed! We're dooooooooooooooomed!
Re:I know what's up. (Score:5, Funny)
dooooooooooooooooooooooooooomed!
(it's a Futurama joke...)
Parent
Re:I know what's up. (Score:4, Funny)
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Re:I know what's up. (Score:5, Informative)
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Re:I know what's up. (Score:5, Funny)
I keep seeing all these comments on the blog about all that He has done for us, what He has bestowed upon us, that He has given us this sun for light and heat and beauty...
I really think H should get more of the credit though. He is merely a byproduct.
Parent
I congratulate you, sir (Score:3, Funny)
+5 informative for "RTFA", outstanding!
Re:I know what's up. (Score:4, Funny)
We're all screwed...
No. Now he got laid. Didn't u read he is unusual calm after mass ejection!!!
Parent
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Finally!
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Apparently
Re:Finally have tools to monitor... (Score:5, Informative)
I am by no means an expert, much less an advanced knowledgeable person when it comes to this stuff, I just find it interesting and hope some of you will as well.
I read an article over a year ago about how they could not get good measurements of solar flares because the instruments were not good enough and to get some measurements you needed at least two observation points some distance apart. (probably related to measuring gamma rays) It is my understanding that the earth finally has the right kinds of instruments up there to get very accurate measurements of the sun, solar flares and etc.... I searched around and have provided a few links. I believe you will really like the Youtube video, very cool. Enjoy!
The Solar/SMO [wikipedia.org] was planned for 2003 and was finally launched on February 7, 2008. It is designed to measure solar radiation with wavelenghts from 200 nanometers - 100 micrometers. This covers the near-ultraviolet, visible and infrared areas of the spectrum. Here is NASA on Solar / SMO [nasa.gov].
Hinode [wikipedia.org] launched in September 2006 has a three year mission to explore the magnetic fields of the sun. Specifically the investigates the interaction between the Sun's magnetic field and its corona. A consortium including Japan, US, UK and Norway worked together to measure the effects of "magnetic fields thought to be the source of solar flares" Three instruments are used, they are the SOT (Solar Optical Telescope, the X-Ray Telescope (XRT), and the Extreme Ultraviolet Imaging Spectrometer (EIS). The first images were captured on October 28.
HESSI renamed RHESSI [nasa.gov] launched on February 5, 2002, captures solar flares, X-rays and gamma ray flashes. Prior to the launch of RHESSI, we only had the GOES spacecraft which only measured X-ray flux and to classify the size of solar flares. YouTube on HESSI / RHESSI; A solar flare [youtube.com] video - no sound. Here is a great video [youtube.com] that shows the various instruments in action, one right after the other. From 10/18/03 through 11/07/03; AR 10486 & AR 10488.
From the Wiki,
The most powerful flare of the last 500 years is believed to have occurred in September 1859: it was seen by British astronomer Richard Carrington and left a trace in Greenland ice in the form of nitrates and beryllium-10, which allow its strength to be measured today (New Scientist, 2005).
Prior to the above launches, the Ulysees was pretty much it for measuring from space, before Ulysses there was only observations from the ground.
Ulysses (17 year mission) [wikipedia.org] - was equipped with instruments to characterize fields, particles, and dust, and was powered by a radioisotope thermoelectric generator (RTG). Launched in 10/6/90 through 7/1/08; through "through triangulation (or, more specifically, multilateration). Each spacecraft has a gamma-ray detector, with readouts noted in tiny fractions of a second. By comparing the arrival times of gamma showers with the separations of the spacecraft, a location can be determined, for follow-up with other telescopes. Because gamma rays travel at the speed of light, wide separations are needed." Additional discoveries: Additional discoveries: [15] 1) Ulysses discovered that the Sun's magnetic field interacts with the Solar system in a more complex fashion than previously believed. 2) Ulysses discovered that dust coming into the solar system from deep space was 30 times more abundant than previously expected.
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