lunedì 12 maggio 2014
NASA Spots Square-Shaped 'Hole' in the Sun (Video)
A NASA spacecraft has made a surprising find on the surface of the sun: a square-shaped "hole" in the star's outer atmosphere.
The dark square on the sun, known as a "coronal hole," is an area where the solar wind is streaming out of the sun at superfast speeds. NASA captured a video of the sun's square-shaped coronal hole between Monday and Wednesday (May 5-7) using the powerful Solar Dynamics Observatory (SDO).
The coronal hole appears dark in the NASA view because there is less material emitting light in the ultraviolet range of the spectrum used to make the video, according to a NASA video description. [Biggest Solar Storms of 2014 (Photos)]