The Observable Universe
How far can you see? Everything you can see, and everything you could possibly see, right now, assuming your eyes could detect all types of radiations around you -- is the observable universe. In light, the farthest we can see comes from the ...
A Road to the Stars
Pictured -- a very scenic road to the stars. The road approaches La Silla Observatory in Chile, with the ESO's 3.6-meter telescope just up ahead. To the left are some futuristic-looking support structures for the planned BlackGEM telescopes, an ...
Star Formation in the Eagle Nebula
Where do stars form? One place, star forming regions known as "EGGs", are being uncovered at the end of this giant pillar of gas and dust in the Eagle Nebula (M16). Short for evaporating gaseous globules, EGGs are dense regions of mostly ...
Colorful Airglow Bands Surround Milky...
Why would the sky glow like a giant repeating rainbow? Airglow. Now air glows all of the time, but it is usually hard to see. A disturbance however -- like an approaching storm -- may cause noticeable rippling in the Earth's atmosphere. These ...
Point Reyes Milky Way
Northern winter constellations and a long arc of the Milky Way are setting in this night skyscape looking toward the Pacific Ocean from Point Reyes on planet Earth's California coast. Sirius, alpha star of Canis Major, is prominent below the ...
When Rainbows Smile
Want to see a rainbow smile? Look near the zenith (straight up) when the sun is low in the sky and you might. This example of an ice halo known as a circumzenithal arc was captured above a palm tree top from Ragusa, Sicily on February 24. The ...
Globular Star Cluster 47 Tuc
Globular star cluster 47 Tucanae is a jewel of the southern sky. Also known as NGC 104, it roams the halo of our Milky Way Galaxy along with some 200 other globular star clusters. The second brightest globular cluster (after Omega Centauri) as ...
A Flower-Shaped Rock on Mars
It is one of the more unusual rocks yet found on Mars. Smaller than a penny, the rock has several appendages that make it look, to some, like a flower. Although it would be a major discovery if the rock was truly a fossilized ancient Martian ...
Moon in Inverted Colors
Which moon is this? It's Earth's moon -- but in inverted colors. Here, the pixel values corresponding to light and dark areas have been translated in reverse, or inverted, producing a false-color representation reminiscent of a black and white ...
A Lion in Orion
Yes, but can you see the lion? A deep exposure shows the famous dark indentation that looks like a horse's head, visible just left and below center, and known unsurprisingly as the Horsehead Nebula. The Horsehead Nebula (Barnard 33) is part of a ...
