APOD: 2023 October 2 Б Sprite Lightning in High Definition
1.10.2023

Sometimes lightning occurs out near space. One such lightning type is red sprite lightning, which has only been photographed and studied on Earth over the past 25 years. The origins of all types of lightning remain topics for research, and scientists are still trying to figure out why red sprite lightning occurs at all.

Aurora and Volcanic Light Pillar
23.09.2014

That's no sunset. And that thin red line just above it -- that's not a sun pillar. The red glow on the horizon originates from a volcanic eruption, and the red line is the eruption's reflection from fluttering atmospheric ice crystals. This unusual volcanic light pillar was captured over Iceland earlier this month.

Sprite Lightning in HD
7.10.2019

This phenomenon occurs in the sky over our heads, not the sea. It is a type of lightning known as red sprite, and rarely has it ever been photographed in this detail. Even though sprites have been recorded for over 30 years, their root cause remains unknown. Some thunderstorms have them, but most don't.

A Lunar Eclipse in Three Exposures
24.01.2000

Our Moon turned red last week. The reason was that during the night of January 20, a total lunar eclipse occurred. The above digitally superimposed photographs captured the Moon three times during this lunar...

The Sun Changes
13.04.1998

Our Sun changes every day. This recent picture was taken in a very specific red color called Hydrogen-Alpha. Dark spots that might appear on the image are usually sunspots, dark magnetic depressions that are slightly cooler than the rest of the Sun's surface.

Mars Through a Small Telescope
19.08.2003

How does Mars appear through a small telescope? Viewed with the unaided eye or through a small telescope, possibly the most striking part of Mars' appearance is it's red color. The color derives from rust, iron oxide, which composes perhaps 10% of the Martian soil.

Orion's Horsehead Nebula
27.08.2000

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the black indentation to the red emission nebula seen just to the right of center of the above photograph. The bright star near the center is located in the belt of the familiar constellation of Orion.

Antares and Rho Ophiuchi
9.05.2004

Why is the sky near Antares and Rho Ophiuchi so colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae. Backlit dust clouds block starlight and so appear dark.

Sagittarius Star Cloud
20.05.2001

Stars come in all different colors. The color of a star indicates its surface temperature, an important property used to assign each star a spectral type. Most stars in the above Sagittarius Star Cloud are orange or red and relatively faint, as our Sun would appear.

The Horsehead Nebula
31.12.2013

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula in the center of the above photograph. The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright red emission nebula.