Moon behind Lava Fountain
3.09.2018

What's happened to the Moon? Nothing, but something has happened to the image of the Moon. The heat from a volcanic lava fountain in the foreground has warmed and made turbulent the air nearby, causing passing light to refract differently than usual.

Comet NEOWISE Rising over the Adriatic Sea
12.07.2020

This sight was worth getting out of bed early. Comet C/2020 F3 (NEOWISE) has been rising before dawn during the past week to the delight of northern sky enthusiasts awake that early. Up before...

Annular Solar Eclipse over New Mexico
30.08.2016

What is this person doing? In 2012 an annular eclipse of the Sun was visible over a narrow path that crossed the northern Pacific Ocean and several western US states. In an annular solar...

Messiers and Mars
15.06.2001

A telescopic tour of the constellation Sagittarius offers the many bright clusters and nebulae of dimensioned space in a starscape surrounding the galactic center. This gorgeous color deep-sky photograph visits two such lovely sights, cataloged by the 18th century cosmic tourist Charles Messier as M8 and M20.

APOD: 2023 September 9 Б Comet Nishimura Grows
8.09.2023

Comet Nishimura is growing. More precisely, the tails C/2023 P1 (Nishimura) are growing as it nears the Sun. Discovered only last month, the comet is already near naked eye brightness as it now moves inside the Earth's orbit.

Fireball Over Edmonton
24.11.2008

What if you're driving down the street and an object from space shoots across the sky right in front of you? Such was the case last week for many people in south central Canada.

An Unusual Mountain on Asteroid Ceres
29.06.2015

What created this large mountain on asteroid Ceres? No one is yet sure. As if in anticipation of today being Asteroid Day on Earth, the robotic spacecraft Dawn in orbit around Ceres took the best yet image of an unusually tall mountain on the Asteroid Belt's largest asteroid.

Highlights of the Summer Sky
26.06.2018

What can you see in the night sky this summer? The featured graphic gives a few highlights for Earth's northern hemisphere. Viewed as a clock face centered at the bottom, early (northern) summer sky events fan out toward the left, while late summer events are projected toward the right.

A Scorpius Sky Spectacular
4.05.2014

If Scorpius looked this good to the unaided eye, humans might remember it better. Scorpius more typically appears as a few bright stars in a well-known but rarely pointed out zodiacal constellation. To get a spectacular image like this, though, one needs a good camera, color filters, and a digital image processor.

Spacecrafts Streak Over Colorado
13.03.2011

Have you ever seen a "star" drifting slowly overhead, but not known what it was? Sometimes even pointing it out to friends or family will only lead to a shrug. What you are seeing...