Deimos Before Sunrise
24.05.2025

Deimos takes 30 hours and 18 minutes to complete one orbit around the Red Planet. That's a little more than one Martian day or sol which is about 24 hours and 40 minutes long, so Deimos drifts westward across the Martian sky.

Comet Holmes Coma Expands
30.10.2007

Go outside tonight and see Comet Holmes. No binoculars or telescopes are needed -- just curiosity and a sky map. Last week, Comet 17P/Holmes underwent an unusual outburst that vaulted it unexpectedly from obscurity into one of the brightest comets in recent years.

M57: The Ring Nebula
15.11.2009

It looks like a ring on the sky. Hundreds of years ago astronomers noticed a nebula with a most unusual shape. Now known as M57 or NGC 6720, the gas cloud became popularly known as the Ring Nebula.

NGC 4565: Galaxy on Edge
15.10.2011

Magnificent spiral galaxy NGC 4565 is viewed edge-on from planet Earth. Also known as the Needle Galaxy for its narrow profile, bright NGC 4565 is a stop on many telescopic tours of the northern sky, in the faint but well-groomed constellation Coma Berenices.

Aurora and Fireball Over Norway
5.10.2012

What's happening behind that mountain? A convergence of variable sky spectacles. One night in mid-September near TromsЬ, Norway, high red aurora could be seen shimmering through lower green aurora in a way that created a striking and somewhat unusual violet glow.

Red Planet Red Moon and Mars
9.08.2018

Mars is also known as The Red Planet, often seen with a reddish tinge in dark night skies. Mars shines brightly at the upper left of this gorgeous morning twilight view from Mornington Peninsula, Victoria, Australia, but the Moon and planet Earth look redder still. Taken on July 27, the totally eclipsed Moon is setting.

Venus, Mercury, and the Waning Moon
14.11.2020

Yesterday, early morning risers around planet Earth were treated to a waning Moon low in the east as the sky grew bright before dawn. From the Island of Ortigia, Syracuse, Sicily, Italy this simple snapshot found the slender sunlit crescent just before sunrise.

Antares and Rho Ophiuchi
21.05.2000

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.

The View from Everest
6.03.2005

What would it be like to stand atop the tallest mountain on Earth? To see a full panoramic vista from there, scroll right. Visible are snow peaked mountains near and far, tremendous cliffs, distant plateaus, the tops of clouds, and a dark blue sky. Mt.

Perseid Trail
14.08.2008

This bright and colorful meteor flashed through Tuesday's early morning skies, part of the annual Perseid Meteor Shower. The lovely image is one of over 350 frames captured on August 12 from...