An Extremely Long Filament on the Sun
9.02.2015

Yesterday, the Sun exhibited one of the longest filaments ever recorded. It may still be there today. Visible as the dark streak just below the center in the featured image, the enormous filament extended across the face of the Sun a distance even longer than the Sun's radius -- over 700,000 kilometers.

Solstice Sun and Milky Way
21.12.2021

Welcome to December's solstice, first day of winter in the north and summer for the southern hemisphere. Astronomical markers of the seasons, solstice and equinox dates are based on the Sun's place in its annual journey along the ecliptic, through planet Earth's sky.

Orange Sun Oozing
6.11.2011

The Sun's surface keeps changing. The above movie shows how the Sun's surface oozes during a single hour. The Sun's photosphere has thousands of bumps called granules and usually a few dark depressions called sunspots.

Space Station, Solar Prominences, Sun
4.05.2021

That's no sunspot. It's the International Space Station (ISS) caught passing in front of the Sun. Sunspots, individually, have a dark central umbra, a lighter surrounding penumbra, and no Dragon capsules attached.

Large Sunspots Now Crossing the Sun
10.07.2013

One of the largest sunspot regions in recent years is now crossing the Sun. This region of convoluted magnetic fields may well produce a solar flare that releases a cloud of energetic particles into the Solar System.

APOD: 2024 May 15 Б AR 3664 at the Suns Edge
15.05.2024

What did the monster active region that created the recent auroras look like when at the Sun's edge? There, AR 3664 better showed its 3D structure. Pictured, a large multi-pronged solar prominence...

Gaia: Here Comes the Sun
26.09.2016

What would it look like to return home from outside our galaxy? Although designed to answer greater questions, recent data from ESA's robotic Gaia mission is helping to provide a uniquely modern perspective on humanity's place in the universe.

Sunspot Group AR 2339 Crosses the Sun
29.06.2015

How do sunspots evolve? Large dark sunspots -- and the active regions that contain them -- may last for weeks, but all during that time they are constantly changing. Such variations were particularly apparent...

APOD: 2023 October 8 Б Plane, Clouds, Moon, Spots, Sun
8.10.2023

What's that in front of the Sun? The closest object is an airplane, visible just below the Sun's center and caught purely by chance. Next out are numerous clouds in Earth's atmosphere, creating a series of darkened horizontal streaks.

Planets In The Sun
5.05.2000

Today, all five naked-eye planets (Mercury, Venus, Mars, Jupiter, Saturn) plus the Moon and the Sun will at least approximately line-up. As viewed from planet Earth, they will be clustered within about 26 degrees, the closest alignment for all these celestial bodies since February 1962, when there was a solar eclipse!