A February without Sunpots
6.03.2019

Where have all the sunspots gone? Last month the total number of spots that crossed our Sun was ... zero. Well below of the long term monthly average, the Sun's surface has become as unusually passive this solar minimum just like it did 11 years ago during the last solar minimum.

AR2835: Islands in the Photosphere
2.07.2021

Awash in a sea of incandescent plasma and anchored in strong magnetic fields, sunspots are planet-sized dark islands in the solar photosphere, the bright surface of the Sun. Found in solar active regions, sunspots...

APOD: 2023 July 11 Б Sunspots on an Active Sun
11.07.2023

Why is our Sun so active now? No one is sure. An increase in surface activity was expected because our Sun is approaching solar maximum in 2025. However, last month our Sun sprouted more sunspots than in any month during the entire previous 11-year solar cycle -- and even dating back to 2002.

APOD: 2026 February 8 Б Active Sunspot Region 4366 Crosses the Sun
8.02.2026

An unusually active sunspot region is now crossing the Sun. The region, labelled AR 4366, is much larger than the Earth and has produced several powerful solar flares over the past ten days. In the featured image, the region is marked by large and dark sunspots toward the upper right of the Sun's disk.

Traces of the Sun
21.12.2016

This year the December Solstice is today, December 21, at 10:44 UT, the first day of winter in the north and summer in the south. To celebrate, watch this amazing timelapse video tracing the Sun's apparent movement over an entire year from Hungary.

APOD: 2023 March 28 Б A Multiple Green Flash Sunset
28.03.2023

Yes, but can your green flash do this? A green flash at sunset is a rare event that many Sun watchers pride themselvesбon having seen.б Once thought to be a myth, a green flash is now understood to occur when the Earth's atmosphere acts like both a prism and a lens.

Filaprom on the Western Limb
24.06.2022

A solar filament is an enormous stream of incandescent plasma suspended above the active surface of the Sun by looping magnetic fields. Seen against the solar disk it looks dark only because it's a little cooler, and so slightly dimmer, than the solar photosphere.

Leaning Tower, Active Sun
1.04.2022

The natural filter of a hazy atmosphere offered this recognizable architecture and sunset view on March 27. Dark against the solar disk, large sunspots in solar active regions 2975 and 2976 are wedged between the Duomo of Pisa and its famous Leaning Tower.

Launch of the Parker Solar Probe
15.08.2018

When is the best time to launch a probe to the Sun? The now historic answer -- which is not a joke because this really happened this past weekend -- was at night. Night, not only...

Pixels in the Sun
26.06.2021

These two panels, composed of video frames made with a safe solar telescope and hydrogen alpha filter, show remarkably sharp details on the solar disk and giant prominences along the Sun's edge on June 6 (top) and June 18.