These images of the Sun were taken at 10:08 am EDT on September 5, 2013 with a hydrogen-alpha telescope at the Phoebe Waterman Haas Public Observatory at the Museum in Washington, DC.
The white-light image on the left shows the surface of the Sun. The red image shows the Sun's lower atmosphere.
On this date, activity on the Sun entered a lull. For at least the next ten days, the Earth-facing side of the Sun displayed only small, inactive sunspots with no chance of solar flares.
The inactivity is surprising, considering that the Sun is at the maximum of its current fourteen-year sunspot cycle, and that NASA has reported that the Sun is currently switching the polarity of its magnetic field. This sunspot cycle appears to be the weakest in a hundred years. It is also likely that this sunspot cycle is double-peaked, and this inactivity might be the dip between the two peaks of activity.
Even during a quiet time like this, the atmosphere of the Sun can still show a number of interesting features, including long, dark filaments snaking across the Sun, and bright prominences sticking out.
Telescope: Lunt 100mm hydrogen-alpha
Camera: Lumenera SKYnyx 2-2M
Image Number: WEB13321-2013
Credit: Image by Smithsonian Staff, Phoebe Waterman Haas Public Observatory
For print or commercial use, please contact: Smithsonian Institution
Reproductions are not currently available. If you would like to use this image as-is, please submit a permission request.