Incredible Images of the Sun

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."

Comments

Re:Hmm

[teridon]

On the contrary:

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.

Re:Slashdotted.

[bluFox]

You can access the first image here
sunspot
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

Unwarranted

[CharlieO]

And this is Michael's fault how?

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...

Adaptive Optics

[Hawaiian Lion]

The technology used by this telescope to counter the effects of the atmosphere in measurements is called adaptive optics. This is the first application I know of for adaptive optics on a solar telescope.

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 and Gemini Project . 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

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.

Cooling question

[forged]

How does the cameras sensors not melt and achieve good accuracy by staring into the sun ? Surely they must be cooled off, but how ? The overclocking crowd here must have some insights !

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

[Squeak]

Increasing the aperture of a telescope has two effects:
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.

GIFs quite common in sat imaging

[CharlieO]

From my days doing Earth Observation Science (EOS) I recall that a lot of satellite imaging, whether astronomical or remote sensing, seemed to follow a de-facto standard of a 512 x 512 x 8bit image tile per channel on the instrument.

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.

Re:Site is slow -- here's the content

[Anonymous Coward]

Dang, couldn't get it perfectly right (used the "code" selection to get past the lameness filter). Maybe that bit at the top could represent a solar flare... :)

Anyone make a proper circle?

Re:Buried in the site

[LHorstman]

For distances of 100 miles that may be true. However we really do need enhanced imaging on the battlefield. As the gunner of an M1A1 Abrams main battle tank, I can kill a target at 3500 meters, but I can't tell what it is. For all I know it could be a friendly vehicle. At 3500 meters it's very difficult to tell the difference between an allied Canadian Leopard 2 and an Iraqi T-72. Recent upgrades to the M1A2's include higher power lenses (up to 50x), which help for identification, but remove your view of most of the battlefield. A very sharp image would have a huge benefit in preventing fratricide. Certainly we do not need the extreme image enhancing done in this article, but something scaled down would be great.

Re:GIFs???

[Fishstick]

Heh, thought the same thing in about .0001 second from seeing that image.

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???

[Fishstick]

er, sorry to reply to my own post...

APOD: January 6, 1997 - Blue Sun Glaring

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.

Re:do the mods actually read these posts ?

[a7244270]

soz. I'm agravvated by a recent trend, and I guess I took it out on you. Dude.

Last week someone posted an incorrect formula for Bayesian filtering and got modded up to 5, and before that someone posted a completely bogus discussion of processor pipelining which also got modded up to 5.

Seems like all you have to do is provide the illusion of information to get modded up.

Re:Hmm

[Peterus7]

What amazes me is that in essence each one of those bright cells are as big as Texas, and that the level of resolution is so fuggin high. How did they get it that sharp?