A Long Snaking Filament on the Sun
13.09.2022

Earlier this month, the Sun exhibited one of the longer filaments on record. Visible as the bright curving streak around the image center, the snaking filament's full extent was estimated to be over half of the Sun's radius -- more than 350,000 kilometers long.

The Edge of Space
24.07.2021

Where does space begin? For purposes of spaceflight some would say at the Karman line, currently defined as an altitude of 100 kilometers (60 miles). Others might place a line 80 kilometers (50 miles) above Earth's mean sea level.

Large Sunspot Groups 10484 and 10486
27.10.2003

Two unusually large sunspot groups are now crossing the face of the Sun. Each group, roughly the size of Jupiter, is unusual not only for its size but because it is appearing over three years after solar maximum, the peak of solar surface activity.

Meteors and Aurorae over Iceland
7.08.2013

What's going on behind that volcano? Quite a bit. First of all, the volcano itself, named Kirkjufell, is quite old and located in western Iceland near the town of GrundarfjЖrПur. In front...

Violent Sunspot Group AR 1302 Unleashes a Flare
28.09.2011

One of the most active sunspot groups in years is currently crossing the Sun. AR 1302 first came around the Sun's edge last week and is so large it can be seen without a telescope.

APOD: 2024 March 12 Б A Galaxy Shaped Rocket Exhaust Spiral
12.03.2024

What's that over the horizon? What may look like a strangely nearby galaxy is actually a normal rocket's exhaust plume -- but unusually backlit. Although the SpaceX Falcon 9 rocket was launched from...

APOD: 2024 August 18 Б A Solar Prominence Eruption from SDO
18.08.2024

One of the most spectacular solar sights is an erupting prominence. In 2011, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressively large prominence erupting from the surface. The dramatic explosion was captured in ultraviolet light in the featured time lapse video covering 90 minutes, where a new frame was taken every 24 seconds.

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.

Sunspots and Silhouettes
4.07.2012

What stands between you and the Sun? Apparently, as viewed from Paris last week, one visible thing after another. First, in the foreground, is the Basilica of the Sacred Heart, built in the late 1800s and located on the highest hill in Paris, France.

Moon Shadow on Jupiter
27.04.2022

What is that large dark spot on Jupiter? It's the shadow of Io, one of Jupiter's largest moons. When Jupiter's moons cross between the Jovian giant and the Sun, they created shadows just like when the Earth's moon crosses between the Earth and the Sun.