5/22/2002: Sun gas
 

http://cellar.org/2002/sungas.jpg

As Bruce Willis said on Moonlighting, "What's wrong with small gas leaks? I have 'em all the time!"

But when the sun has a gas leak, it's a remarkable thing. This shot taken by NASA's TRACE spacecraft shows loops of hot, electrified gas rising from the surface of the sun. The loops follow magnetic field lines, and can span a length of 250,000 miles, or about 30 times the diameter of Earth.

30 times. The diameter. Of the Earth.

I read that these things were hopping around at the speed of sound. Quite magnificent!

If you thought that was cool, check this out....
 

<a href="http://www.boulder.swri.edu/~deforest/trace_april2002_xflare.mpg">
Here</a>'s a movie I just finished making from TRACE archive data. It's a solar flare that happened on 21-April-2002. You can see images of it on the <a href="http://vestige.lmsal.com/TRACE">TRACE website</a> or the <a href="http://sohowww.nascom.nasa.gov">SOHO site</a>.

<p>TRACE is a small satellite in low Earth orbit; SOHO is a large observatory stationed at L-1. Because TRACE is newer it has about 5x better resolution than the instruments aboard SOHO -- but it will likely re-enter Earth's atmosphere in a couple of years.

<p>The movie has been rotated so that solar west is UP (that image was rotated the same way), and has been resampled to 2 minutes per frame, for five hours of original time. In both the still image and the movie you're seeing extreme ultraviolet light emitted by Fe 11+ -- iron that's stripped of 11 of its electrons by the intense heat -- at about 2,000,000 Centigrade.

<p>The big bright slinky thing is about 10-15 Earth diameters tall.

<p>The amount of energy released is equivalent to covering the entire surface of the Earth more than 10 meters deep in TNT and setting it all off.

<p>The last time one of these things pointed in the general direction of Earth (last October), it caused aurorae that stretched as far south as San Diego.

By the way...
 

<a href="http://vestige.lmsal.com/TRACE">TRACE</a> is the first NASA spacecraft I know of that offers its data free to everybody immediately. From their website you can search their database and get the same kind of data that we solar physicists get -- that's how we get it, too.
<p>If you want to work with the data, a fine tool to do so is <a href="http://pdl.perl.org">PDL</a>, a variant of perl that's designed for high powered data analysis.

For the love of God, 'Toad, please don't show us any MOON GAS!
 

'mmmmkay?

Wow, Zowie, good work. That video is worth the download.

Thanks!
 

This stuff just blows me away -- that is to say, getting solar data over the internet. The original Skylab data are still available -- you know, don't you, that our nation's first space station was also a solar observatory? -- but very hard to get nonetheless.

<p>Not that anyone is trying to stop you from getting to them -- it's just that the Skylab data are all sitting on film that was hand carried back from orbit by astronauts. So they're sitting in vaults at the Naval Research Laboratory in Washington, D.C. If you want to look at them, you have to phone up and ask the curators (they're nice guys), and then fly out to D.C. with your gear and your jeweler's loupe. Then you look at the picture on a light table and measure it with calipers. If you see something cool you send it down to the photo shop and iterate till the prints look right.

<p>SOHO and TRACE (and now RHESSI) data are available pretty much right away, pretty much anywhere. That means (for example) that the <a href="http://www.sec.noaa.gov">National Space Environment Center</a> can use the scientific data to predict power and radio outages here at Earth -- which in turn is a Good Thing.

Are you an amateur astronomer, or do you have a professional interest in this? (In either case it's more noble than my interest in these kinds of space images: I like 'em because they're just so mind-boggling. Colliding galaxies, can you imagine?)

professional solar physicist
 

... which, by the way, is a field that's very good to go into at the moment. The data are way cool, the physics is challenging, and there's a lot more demand than new entrants into the field.

Can anyone estimate the size of the large loop in the center of the pic? I know T's post mentioned these things can get to 250K miles in size, but what about this one in particular?

It's 340 pixels. This instrument has about 350 km/pixel, so it's
about 120 megameters -- 75,000 miles. Earth's diameter
is about 10,000 miles, so this particular loop is about 7-8
Earth diameters.

A Beautiful Mind
 

John Nash could.

He'd just take the arc of the sun in the photo ... work in the distance of the circumference of the sun ... wave his hand in front of your face ... mumble something to himself and ... guess the right answer!

wowie zowie ... i hadn't thought of working off the circumference of the sun in pixels. :cool:

Holy crap!! That's quite large. Almost as large as a zit in the middle of the noggin feels. Kinda looks the same, now that I think about it.
Thanks for the info, zowie.

Re: A Beautiful Mind
 

Actually, you're thinking of John von Neumann. He was a bit of a showman during his time. Once at a party, a woman walked up to him and posed a math riddle, "Supposed two trains are headed towards each other at 60mph, 60 miles apart. A fly is flying back and forth between the two trains at 120mph, until the trains collide and crush him. How far will he have flown before getting crushed?"
There are two ways to do this problem: You can set up an infinite sum and find the convergence point (that's what I did), or you can realize the trick -- the trains will meet in 30 minutes (60 miles apart, 60mph), therefore the fly is travelling 120mph for 30min, or a distance of 60 miles.
Almost immediately after hearing the riddle, John looked at the woman and said, "60 miles."
She replied, "Wow! That's great -- most people don't realize the trick -- they use an infinite sum."
To which he replied, "What trick?"
The guy had some wicked brain power. He could remember lines from books and excerpts from papers verbatim years after reading them.

Kudos to those who might be able to put this limerick to words: (144 + 12 + 20 + 3sq4)/7 + (5 * 11) = 9^2 + 0

Spoiler alert! Don't scroll down until you've solved the puzzle. To read the solution, hold your monitor up to a mirror. :D BTW, anyone know if reverse-printing could be added to this board?

Hmm, there's a spare syllable in there, did I mess it up?