Blue Sun Glaring
6.01.1997

The Sun is a bubbling ball of extremely hot gas. In this false-color picture, light blue regions are extremely hot - over 1 million degrees, while dark blue regions are slightly cooler. The camera filter used was highly sensitive to the emission of highly charged iron ions, which trace the magnetic field of the Sun.

Blue Sun Bursting
20.05.2013

Our Sun is not a giant blueberry. Our Sun can be made to appear similar to the diminutive fruit, however, by imaging it in a specific color of extreme violet light called CaK that is emitted by the very slight abundance of ionized Calcium in the Sun's atmosphere, and then false color-inverting the image.

Far Side of the Sun
3.05.2001

You may think it's impossible to see through the Sun, but maps of the Sun's far side are now made routinely by instruments on board the sun-staring SOHO spacecraft. This is one such map from April 12.

Sunspot Castle
12.11.2011

Each day can have a beautiful ending as the Sun sets below the western horizon. This week, the setting Sun added naked-eye sunspots to its finale, as enormous active regions rotated across the dimmed, reddened solar disc.

APOD: 2024 September 2 Б A Triangular Prominence Hovers Over the Sun
2.09.2024

Why is there a triangle hovering over the Sun? Although the shape is unusual, the type of structure is not: it is part of an evolving solar prominence. Looping magnetic fields on the Sun channel the flow of energetic particles, sometimes holding glowing gaseous structures aloft for months.

Time Lapse Auroras Over Norway
28.03.2011

Sometimes, after your eyes adapt to the dark, a spectacular sky appears. Such was the case earlier this month when one of the largest auroral displays in recent years appeared over northern locations like the border between Norway and Russia.

APOD: 2023 May 17 Б Sunspot with Light Bridge
17.05.2023

Why would a small part of the Sun appear slightly dark? Visible is a close-up picture of sunspots, depressions on the Sun's surface that are slightly cooler and less bright than the rest of the Sun. The Sun's complex magnetic field creates these cool regions by inhibiting hot material from entering the spots.

APOD: 2024 July 28 Б Sun Dance
28.07.2024

Sometimes, the surface of our Sun seems to dance. In the middle of 2012, for example, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence that seemed to perform a running dive roll like an acrobatic dancer.

AR1520: Islands in the Photosphere
14.07.2012

Awash in a sea of plasma and anchored in magnetic fields, sunspots are planet-sized, dark islands in the solar photosphere, the bright surface of the Sun. Dark because they are slightly cooler than the surrounding surface, this group of sunspots is captured in a close-up telescopic snapshot from July 11.

Half Sun with Prominence
2.11.2020

What's happening to the Sun? Clearly, the Sun's lower half is hidden behind a thick cloud. Averaging over the entire Earth, clouds block the Sun about 2/3rds of the time, although much less over many land locations. On the Sun's upper right is a prominence of magnetically levitating hot gas.