A Complete Solar Cycle from SOHO
3.12.2007

Every eleven years, our Sun goes through a solar cycle. A complete solar cycle has now been imaged by the sun-orbiting SOHO spacecraft, celebrating the 12th anniversary of its launch yesterday. A solar cycle...

An Aurora Cupcake with a Milky Way Topping
9.09.2014

This sky looked delicious. Double auroral ovals were captured above the town lights of жstersund, Sweden, last week. Pictured above, the green ovals occurred lower to the ground than violet aurora rays above, making the whole display look a bit like a cupcake.

Dragon Aurora over Iceland
18.02.2019

Have you ever seen a dragon in the sky? Although real flying dragons don't exist, a huge dragon-shaped aurora developed in the sky over Iceland earlier this month. The aurora was caused...

A Giant Starspot on HD 12545
12.07.2000

What could cause a star to have such a large spot? Our Sun itself frequently has sunspots, relatively cool dark magnetic depressions that move across its surface. HD 12545, however, exhibits the largest starspots yet observed.

Flare Well AR2673
14.09.2017

Almost out of view from our fair planet, rotating around the Sun's western edge giant active region AR2673 lashed out with another intense solar flare followed by a large coronal mass ejection on September 10.

Brown Sun Bubbling
10.01.2000

Our Sun may look like all soft and fluffy, but its not. Our Sun is an extremely large ball of bubbling hot gas, mostly hydrogen gas. The above picture was taken in a specific color of light emitted by hydrogen gas called Hydrogen-alpha.

The Sun Today
18.05.1996

Our Sun shows a different face every day. The above picture was taken on May 15, but a similar picture of the Sun actually taken today can be found here. The above picture was taken in red light and so is shown in red.

Venus Transit 2012
7.06.2012

Occurring in pairs separated by over a hundred years, there have now been only eight transits of Venus since the invention of the telescope in 1608. The next will be in December of 2117.

Mercury Crosses a Quiet Sun
2.12.2019

What's that black dot crossing the Sun? The planet Mercury. Mercury usually passes over or under the Sun, as seen from Earth, but last month the Solar System's innermost planet appeared to go just about straight across the middle.

Mercury Transits the Sun
13.05.2003

How big is the Sun? The Sun is not only larger than any planet, it is larger than all of the planets put together. The Sun accounts for about 99.9 percent of all the mass in its Solar System.