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Incredible Images of the Sun
Posted by
michael
on Thu Nov 14, 2002 08:01 AM
from the it's-the-yellow-thing.-outside. dept.
from the it's-the-yellow-thing.-outside. dept.
shelterit writes "A new swedish telescope facility in La Palma uses a new technology to remove the blurriness of the atmosphere to snap new and astonishingly sharp images of the sun. Want to have a closer look at the surface of it? Reminds me of paintings I did as a kid."
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GIFs??? (Score:5, Insightful)
Re:GIFs??? (Score:5, Informative)
Parent
Look at art! (Score:3, Funny)
If you scroll down to the "bottom" of that image, line yourself up with the very top of that monstrous sunspot and then cut directly left, you can see a nearly perfect image of a face.
*sigh*
Now I guess we sit back and wait for the conspiracy theories to fly.
Re:Look at art! (Score:4, Funny)
It's a miracle!!!
Parent
Re:Look at art! (Score:5, Funny)
Seriously though, this is just another example of how the human brain is hot-wired to see faces in everything - even a colon, a dash and a bracket.
Parent
Pictures in the flames (Score:4, Informative)
It's a phenomenon known as pareidolia [skepdic.com], and is quite a fascinating subject in its own right. Briefly, the human mind tends to seek patterns that it recognizes. When faced with a chaotic input, the mind creates patterns where none exist. Carl Sagan argues that faces in particular are hardwired into our recognition centres.
Incidentally, I can't see the face you're talking about there. (I'm probably not tired enough, as I find I'm very prone to seeing faces everywhere after an all-nighter.)
I did find a yin/yang symbol, though...
Parent
Re:GIFs??? (Score:3, Funny)
You can see all the horns at the top! Just above the central blackness! It's Satan and his minions! Reverend Bobby was RIGHT! It's the SCIENTISTS and all of their TECNOLOGY have finally!!! opened the DOOR TO HELL!!!!! He said they put DAEMONS in our computers, and on the InterNet, but I didn't believe!
Oh, JESUS, I am heartily sorry for the sins I have committed, and I reject the **EVIL** TECNOLOGY of the SCIENTISTS and their DAEMONS! Have Mercy On ME, oh LORD, and on my brother, Willum Jeffry Scraggins, who now lives in New York under the name of Will Craig, and also on his wife Rachel (though she is an Unbeliever, if you know what I mean).
Re:GIFs??? (Score:3, Interesting)
But, when I loaded it up, the color is just too intense. I tend to like softer blue patterns for my desktop (NT/W2k "Soap Bubbles" usually does the trick).
I used to have one that was rendered in blue (think it was an x-ray image or something) of the whole sun, made a nice soothing wallpaper on my CDE desktop. Wonder if I can find that one again (think it was originally linked from Blues News).
Re:GIFs??? (Score:4, Interesting)
APOD: January 6, 1997 - Blue Sun Glaring [nasa.gov]
Explanation: The Sun is a bubbling ball of extremely hot gas. In this false-color picture, light blue regions are extremely hot - over 1 million degrees, while dark blue regions are slightly cooler. The camera filter used was highly sensitive to the emission of highly charged iron ions, which trace the magnetic field of the Sun. The rich structure of the image shows the great complexity of the Sun's inner corona. A small active region can be seen just to the right and above center. This picture was taken in ultraviolet (extremely blue) light by the Extreme-ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory (SOHO) spacecraft, which is orbiting the Sun just ahead of the Earth, at the L1 point. SOHO was launched in 1995 and will continually monitor the Sun for several years.
I just think that's one of the coolest things I've ever seen. I'll use that for my desktop again, now that I've found it again.
Parent
GIFs quite common in sat imaging (Score:5, Interesting)
GIFs were often used because it is a very stable way of doing lossless compression at 8bit, stable as in almost any image program can read them.
This is not the case with TIFFs as there are a number of variants and options in the file format.
TIFFs are however a better medium for storage of composite images, either spatially or spectorally (montages or multichannel pseudo colour in english).
Due to its general lack of use as a data storage format most of the tools I used/wrote to proccess image data files generally did not have JPEG support or other common 'display' options as the file is regarded as data, not an image - its a subtle difference but explains the mindset.
When I published stuff on the web I'd run our raw large images through Photoshop to get pleasing images but compact file sizes.
It may not have occured for them to do this, and anyway they may regard this as publishing data for other interested parties to download and process themselves.
Parent
Re:GIFs??? (Score:3, Informative)
The sun?! Where?! (Score:5, Funny)
Re:The sun?! Where?! (Score:5, Funny)
Of course, I also live in Sweden and post on Slashdot, so I know that of which I speak.
Parent
Also on MSNBC (Score:5, Informative)
Re:Also on MSNBC One Question from article. (Score:4, Informative)
The real reason they are "dark" is that they are cooler than the gas aronud them. Not that they are cold of course. From one of my astro textbooks:
Temperature of sunspot: 3900K
Temperature of surrounding photosphere: 5780K
Resulting in approximately 1/5 the flux (bolometric flux goes as T^4).
Doug
Parent
re Paintings as a kid (Score:5, Funny)
Buried in the site (Score:5, Informative)
Re:Buried in the site (Score:3, Insightful)
That being said, I would be very surprised if there weren't military spy satellites, and perhaps reconnaisance planes, already using this.
I see (Score:5, Funny)
Appology (Score:5, Funny)
Re:Appology (Score:5, Funny)
No problem. Mirrors available: here [uoregon.edu]
Parent
Summer Fun (Score:5, Funny)
another link (Score:5, Informative)
This article [space.com] has the links.You can also zoom in and use the viewer.
Just what we need (Score:5, Funny)
Photos like these will show us where the potential landing sites are. Very useful since the lander will have to find somewhere that's not only flat but free of excessive RF noise so that we can communicate with Earth.
So, obviously, someone will ask - How can we possible build something to get to the sun? Well, this is quite simple, Firstly we use regrigeration devices. These will require some considerable energy, as well as a decent fusion power source to keep them going. Secondly, we avoif reflective surfaces. The other thing to remember is that we only need to travel during the night. During the day is when the sun is hottest, so travel at night should help cool us considerably. This will require better propulsion mechanisms that can do the bulk of the travelling in the 12 hours of night.
Mirror (Score:5, Funny)
Do you have a screen wipe? (Score:3, Funny)
Re:Mirror (Score:4, Funny)
Parent
mirror! (Score:5, Informative)
extra link. (Score:4, Informative)
Site is slow -- here's the content (Score:5, Funny)
____
/ \
| |
| |
\____/
Hope that helps to beat the Slashdotting.
Wow...that went fast. (Score:5, Funny)
Adaptive Optics (Score:5, Interesting)
This technology has been around for awhile, and was first seriously developed by the military at the Starfire Optical Range
Recently it has been used in such telescope projects as the WM Keck Observatory [hawaii.edu] and Gemini Project [gemini.edu]. I know AO is also used for measurement of eye aberrations, with projects being conducted at several Universities. For more information about Adaptive Optics, I suggest the Center for Adaptive Optics [ucolick.org]
My personal experience with AO was as an intern for Gemini this past summer. I helped write parallel code for a program that simulates current and future adaptive optics systems planned for the next generation of extremely large telescopes.
Re:Adaptive Optics (Score:4, Insightful)
Then you can chuck a frisbee like object through the beam and watch it get zapped
Did I say this was seriously frowned on, I think I should
Adaptive Optics in a Nutshell:
1) You use a single point source as a reference.
2) You know the aberation caused by the atmosphere will spread the point image when you receive it.
3) You know that as your source is a point source, then the resultant spread in your image is entirely due to aberation, so use the image to calculate the Point Spread Function
4) Using the PSF apply a correction to the light path by altering something in the imaging system, usually a mirror.
5) Repeat several hundred times a second
Of course the great side effect is this also removes distortion caused by the imaging system itself, allowing you to use bigger mirrors with a lower tolerance than you otherwise might be able to do.
Originally point sources were strong and predictable stars in the field of view that you wanted - hence the term 'guide stars'
With a laser generated guide star you project a spot onto the upper surface of the atmosphere with a powerful laser of an appropriate frequency - close to your obsering frequency, but far enough out that you don't effect the observation. The subtlety here is to account for the fact that the point source will be spread twice, once on the way up and once on the way down.
Anyone working in AO I apologise to for the somewhat oversimplification - follow the links in the parent to better details if your interest is fired.
Parent
Cooling question (Score:4, Interesting)
Btw, I tried to stare at the sun once when I was a kid, that was stupid. I was told too late that one can go blind for doing that -- that must explain the glasses today...
Re:Cooling question (Score:5, Interesting)
More light is collected. (Since astronomical telescopes are usually used to look at dim objects this is normally considered an advantage.)
To reduce the diffraction effects and so increase the spatial resolution.
When observing the sun, the second of these is still required but the first is a problem. The sun provides too much light, especially in the infrared, to observe safely.
The solution is to place a filter over the front of the telescope which cuts down the amount of light entering the scope. This reduction generally needs to be of the order of 1:1,000,000.
Filters at the back end of the telescope, directly in front of the eyepiece/camera, are not safe. All the heat from the sun passes the scope through and is focused through this small filter. They can then easily crack or melt.
Safety notice: The only safe filters for observing the sun are those designed for the job. They are usually thin plastic, sometimes glass, with a metal coating on both sides. Always check the filter is firmly fixed in place and has no scratches or pinholes. It is this filter type which was used in the eclipse safety glasses a few years back. When observing by eye, with no telescope, binoculars or other magnification, welder's No 14 glass or fully exposed and developed black and white film negatives are also safe. (Not colour film or b&w film developed with a colour process - it is the deposited metallic silver used in the b&w process which provides the protection.) NOTHING else is considered safe.
You can get cooled CCD cameras, and the astrophotographical community has been using them for years. (Well, those than can afford them anyway.) The cooling is required to reduce the 'dark current' within the camera itself during long exposures, not to remove incoming heat.
Parent
Slashdotted (Score:3, Funny)
It's amazing how (Score:3, Funny)
What?
Why are you all looking at me like that?
Mom always told you to not look into the Sun.. (Score:5, Funny)
do it yourself (Score:4, Informative)
I actually do this sometimes for a whole class of students, and for that I need a big, bright image they can all see, so I use the full aperture of my 8-inch scope. You just have to be careful to limit how long you have it pointed at the sun, because the heat can destroy your eyepiece (melts the glue).
OH NO!!!! (Score:5, Funny)
If only we had known this before, maybe we could have done something about it!
11:15) Restate my assumptions (Score:3, Funny)
Sometimes the oldest jokes... (Score:3, Funny)
Re:Hmm (Score:5, Informative)
Parent
Re:Hmm (Score:5, Interesting)
The filaments' newly revealed dark cores are seen to be thousands of kilometers long but only about 100 kilometers wide. Resolving features 100 kilometers wide or less is a milestone in solar astronomy and has been achieved here using sophisticated adaptive optics, digital image stacking, and processing techniques to counter the blurring effect of Earth's atmosphere. At optical wavelengths, these images are sharper than even current space-based solar observatories can produce.
Parent
Re:Hmm (Score:4, Insightful)
By using new technology earth based observatories have made an advance over *current* space based observatories. Doesn't it follow that by using the same advances space based observatories will exceed earth based ones once they can be implemented? Also, they're be no need for correcting for the atmosphere ...
Parent
Re:Wow (Score:3, Funny)
The web server seem to be running "hot" as well.
Re:Slashdotted. (Score:4, Interesting)
sunspot [shacknet.nu]
you should do it fast though , it is my home machine and i cant hold on for long.
ill try to put the other page as sun.html
Parent
Re:Where is the 1600x1200 version? (Score:3, Informative)
whoops
Unwarranted (Score:3, Interesting)
Seriously they chose to put large size images linked from a press release - I mean they're not even deep links, nor is this one near the bottom of the page. Its probably one of the most likely links everyone will click on if they read the story. Its linked from a press release they expect this too be read, its not like we slashdotted a tiny departmental server.
Does moving it from a 2 click (slashdot story - press release image - gif) to 1 click[1] (slashdot story) really justify a personal broadside against the editorial integerity of one the slashdot team?
Comment on the fact that maybe they should be warned so they remove the high res links until the slashdotting is over, maybe comment on the poor web design approach of the academic team involved, any number of these are valid responses to this story.
Your response adds nothing to the story, nor is what I would expect from someone (judging by you name and email) who is experienced at proffesionally critiquing and assess others work in thier career. Or do peer reviews in Academia these days descend to personal attacks, unwarranted sarcasm and flamewars too?
It seems a strange contrast to your statement about stupidity on the site, did you mean the content of the site or the quality and relevance of the posts on it?
[1]1-Click is of course patented by Amazon, so we must be careful...
Re:Hubble? (Score:5, Informative)
Parent