Starship Asterisk*

The Sun in X-rays from NuSTAR

Explanation: Why are the regions above sunspots so hot? Sunspots themselves are a bit cooler than the surrounding solar surface because the magnetic fields that create them reduce convective heating. It is therefore unusual that regions overhead -- even much higher up in the Sun's corona -- can be hundreds of times hotter. To help find the cause, NASA directed the Earth-orbiting Nuclear Spectroscopic Telescope Array (NuSTAR) satellite to point its very sensitive X-ray telescope at the Sun. Featured above is the Sun in ultraviolet light, shown in a red hue as taken by the orbiting Solar Dynamics Observatory (SDO). Superimposed in false-colored green and blue is emission above sunspots detected by NuSTAR in different bands of high-energy X-rays, highlighting regions of extremely high temperature. Clues about the Sun's atmospheric heating mechanisms may not only come from this initial image, but future NuSTAR images aimed at finding hypothesized nanoflares, brief bursts of energy that may drive the unusual heating.

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Cool pic...looks like a Solar Aurora....

:---[===] *

It will be interesting to see how and if this west limb of the sun emission correlates to future events as it seems isolated to only one part of the sun.

http://www.nustar.caltech.edu/image/nustar141222a

Any idea if more is known about the STEREO Behind spacecraft?

http://stereo.gsfc.nasa.gov/

Of course the atmospheres of the Earth and the Sun are extremely different, but could something that happens here on Earth help explain solar coronal heating?

The hottest spots in our atmosphere are caused by electrical discharges aka lightning. Could huge currents flowing in the Sun's already ionized gases contribute to this heating?

Bruce

creo que no se han visto manchas solares en otras estrellas... o sí?
I think they have not seen sunspots on other stars ... or yes?

Rothkko wrote:creo que no se han visto manchas solares en otras estrellas... o sí?
I think they have not seen sunspots on other stars ... or yes?

Interesting question as one of the methods of detecting extra-solar planets involves a slight dimming of the star. How could you differentiate a sunspot from the transit of an exoplanet? Expect a slight gravitation tug too? Or maybe a transit would produce a more profound darkening than a sunspot.

http://en.wikipedia.org/wiki/Methods_of ... exoplanets

Rothkko wrote:I think they have not seen sunspots on other stars ... or yes?

Depends on what you mean by "seen". They have not been resolved optically. But by looking at the light curves produced by eclipsing binaries and by extrasolar planets, their size and structure can be determined and mapped. I'd call that "seeing".

(On other stars they are called starspots.)

Chris Peterson wrote: Depends on what you mean by "seen". They have not been resolved optically. But by looking at the light curves produced by eclipsing binaries and by extrasolar planets, their size and structure can be determined and mapped. I'd call that "seeing".
(On other stars they are called starspots.)

en ningún caso pueden ser confundidas con planetas extrasolares, creo entender
in no case can be mistaken for extrasolar planets, I understand

Rothkko wrote:in no case can be mistaken for extrasolar planets, I understand

They can be, but usually not for long. Differences in the structure of the light curve and variations in periodicity allow them to be distinguished after multiple observations (and some starspots are very long lived- much more so than sunspots).

thanks, Chris
suponía que las manchas estelares eran ordinarias para los astrónomos que buscan planetas extrasolares
supposed that the stellar spots were ordinary for the astronomers who look for extrasolar planets