Milky Way Over Crater Lake with Airglow
19.06.2013

How many different astronomical phenomena have come together to create the above vista? Several. First, in the foreground, is Crater Lake -- a caldera created by volcanism on planet Earth about 7,700 years ago. Next, inside the lake, is water.

The Gegenschein Over Chile
14.01.2014

Is the night sky darkest in the direction opposite the Sun? No. In fact, a rarely discernable faint glow known as the gegenschein (German for "counter glow") can be seen 180 degrees around from the Sun in an extremely dark sky. The gegenschein is sunlight back-scattered off small interplanetary dust particles.

Plato and the Lunar Alps
3.12.2014

The dark-floored, 95 kilometer wide crater Plato and sunlit peaks of the lunar Alps (Montes Alpes) are highlighted in this sharp digital snapshot of the Moon's surface. While the Alps of planet Earth...

Fifty Gravitational Wave Events Illustrated
3.11.2020

Over fifty gravitational wave events have now been detected. These events mark the distant, violent collisions of two black holes, a black hole and a neutron star, or two neutron stars. Most of the 50 events were detected in 2019 by the LIGO gravitational wave detectors in the USA and the VIRGO detector in Europe.

Comet Olbers over Kunetice Castle
31.07.2024

A visitor to the inner solar system every 70 years or so Comet 13P/Olbers reached its most recent perihelion, or closest approach to the Sun, on June 30 2024. Now on a return voyage...

APOD: 2025 February 18 Б Thors Helmet versus the Seagull
17.02.2025

Seen as a seagull and a duck, these nebulae are not the only cosmic clouds to evoke images of flight. But both are winging their way across this broad celestial landscape, spanning almost 7 degrees across planet Earth's night sky toward the constellation of the Big Dog (Canis Major).

Mars Then and Now
11.11.2003

Does Mars have canals? A hot debate topic of the late 1800s, several prominent astronomers including Percival Lowell not only claimed to see an extensive system of long straight canals on Mars, but used them to indicate that intelligent life exists there.

SDO s Multiwavelength Sun
21.12.2013

Today, the solstice is at 17:11 Universal Time, the Sun reaching the southernmost declination in its yearly journey through planet Earth's sky. The December solstice marks the astronomical beginning of winter in the northern hemisphere and summer in the south.

Panoramic Eclipse Composite with Star Trails
29.08.2017

What was happening in the sky during last week's total solar eclipse? This featured little-planet, all-sky, double time-lapse, digitally-fused composite captured celestial action during both night and day from a single location.

Parker vs Perseid
15.08.2018

The brief flash of a bright Perseid meteor streaks across the upper right in this composited series of exposures made early Sunday morning near the peak of the annual Perseid meteor shower.