## Tuesday, December 7, 2010

### New Mega-Filament Captured On Sun.

I'm not a filament expert so I won't write much other than to say: Look at this amazing "Mega-filament" captured by NASA's Solar Dynamics Observatory.
Click on image to watch as a Video.

Image credit: NASA's Solar Dynamics Observatory.  Enjoy. :)

1. Cool. Any speculations or computations on the energetics that caused this? Mechanisms that may determine the largest possible such explosions?

2. AAAAAAAHHHHHHHHGGGGGGGG!!!!!!!!!!!! WE'RE ALL GOING TO DIE!!!!!!!!!!

AAAAAAAAAAHHHHHHHHHHHGGGGGGGGGGGGG!!!!!!!!!

oh wait. it already missed us. ok we're good.

As for the energies involved, I can give my exceedingly expert mis-informed expert opinion and say that it was the equivalent energy of 10^12 atom bombs (using the bomb dropped on Hiroshima as the bench mark) or 10^9 H-bombs (using the Castle-Bravo test as the bench mark), though I could be off by as much as 5 or 6 orders of magnitude, so fairly close.

3. Q42,

I would like to know a bit more about mechanisms and dynamics.

If one were to consider every flares and add up the energetics (like nuclear bombs you used), it would really open eyes at what an average star is compared to our little problems of energy generation... It is really fascinating.

4. My answer was simply a back-of-the-envelope calculation using available sources (google). A solar flare is typically on the order of 10^24 J of energy and the bomb dropped on Hiroshima was ~10^12 J. Thus my 10^12 atom bombs.

For further comparison the US uses ~4 x 10^9 Megawatt-hours of energy per year. 1 Megawatt-hour is 3.6 x 10^9 joules (google calculator), thus the US uses ~1.4 x 10^19 J of energy per year (electricity). This means that a single solar flare has enough energy in it to power the whole US for about 420,000 years. This is of course assuming all the energy can be converted to electrical power. Even using a 1% conversion efficiency, this still gives us 4,200 years of power from one solar flare. As a side note the 10^24 J number is also approximately how much energy strikes the earth from the sun each year, that is the total energy from the sun to the earth for a year. The total output of the sun is 3.86 x 10^26 joules per second (note that is per second, as opposed to the 10^24 number which was per year). This is enough energy to power the entire US for 27.5 MILLION years, and that is the energy output of one second. And the sun has been doing this for 5 billion years, and will do it for another 5 billion years.

We don't have an energy crisis, we have an energy management crisis.

5. Sorry I'm slow getting to this, but a few points: this is actually a coronal mass ejection not a flare. There is often flaring activity associated with CMEs, but not this time. Filaments are relatively cool, dense plasma that gets caught lifted into the corona by magnetic fields. Like flares, however, this is probably caused by very rapid magnetic reconnection which changes the topology of the magnetic field, causing it to launch the plasma out into the heliosphere.

6. Q42 & NN,

If I were to surmise from your posts, it is the local magnetic instablity possibly deep interior that manifested as mass ejection.

I agree that we have energy management crisis, and it applies to all forms of energy, solar, wind, carbon based, and even the nuclear.