Posts by 

C. Alex Young

Sun

Sun activity: M flare from newcomer AR3110!

September 24, 2022. Sun activity perking up with an M1.73 class flare from newcomer sun spot active region AR3110.

Aurora season: Why more auroras at equinoxes?

An aurora season occurs in October and March each year, due to the way the magnetic fields of the sun and the Earth work in conjunction with sun-Earth geometry.
Sun

Sun activity: Week of September 12, 2022

This week started with the return of region AR3088, now labeled AR3102. Activity increased by the weekend with several M flares and the return of region AR3089.
Sun

Sun activity: Week of September 5, 2022

This week started with auroras produced by a geomagnetic storm. With the departure of sunspot region AR3089, sun activity gave way to low-level flaring.
Sun

Sun activity: Week of August 29, 2022

Sun activity for week of August 29, 2022: M flares and activity from AR3088 kicked off an action-packed week that ended with spectacular auroras.
Sun

Sun activity: Week of August 22, 2022

Auroral activity died down then sun activity started quietly with dancing prominences and a strange coronal hole. It ended with a flurry of M flares.
Sun

Sun activity: Week of August 15, 2022

Looking for the current page on sun activity? Click here. Sun activity August 21: Calm sun, more auroras You know...
Sun

Sun activity: Week of August 8, 2022

Looking for the current page on sun activity? Click here. Update August 14: A super-long coronal hole Today’s top sun...

Limb darkening is an optical effect on the sun

Limb darkening is an effect we can see on the sun where the edges of the sun are darker than the center, due to the amount of photosphere we're looking at.
Sun

Sun activity: Week of August 1, 2022

Sun activity for the week of August 1, 2022: Activity remained low on the sun's Earth-facing side, however, plenty of action occurred on the far side.