Explanation:
Two unusually long filaments crossed part of the Sun last week.
The filaments are actually relatively cool and dark
prominences of solar
plasma held up by the Sun's
magnetic field but seen against the
face of the Sun.
Filaments typically last a few weeks before falling back.
Pictured above, the
two filaments are visible on the
Sun's right side.
It would take twenty Earths, set end-to-end, to match the
length of one of the filaments.
Also visible are bright hot regions called
plages and a carpet of hundreds of
granules that provide the Sun's texture.
The above image
was taken early last week through a small telescope in a
very specific color of light emitted primarily by
hydrogen.