Moonrise Over Seattle
11.10.2003

Is the Moon larger when near the horizon? No -- as shown above, the Moon appears to be very nearly the same size no matter its location on the sky. Oddly, the cause or causes for the common Moon Illusion are still being debated.

Analemma Over Ancient Nemea
21.06.2004

An anelemma is that figure-8 curve that you get when you mark the position of the Sun at the same time each day throughout planet Earth's year. Above, 44 separate exposures (plus...

When the Moon Was Young
13.05.2005

Remember when the Moon was young? It was just last Monday. On May 9th, this slender crescent Moon was recorded at a tender age of 34 hours and 18 minutes. Well, OK ... when calculating...

On the Possibility of Ascending to Mars
19.10.2005

On another October 19, in 1899, a 17 year-old Robert Goddard climbed a cherry tree on a beautiful autumn afternoon in Worcester, Massachusetts. Inspired by H.G. Wells' War of the Worlds and gazing...

M31: The Andromeda Galaxy
26.11.2006

Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it.

The Analemma and the Temple of Olympian Zeus
23.12.2006

An analemma is that figure-8 curve you get when you mark the position of the Sun at the same time each day throughout planet Earth's year. Above, 47 separate exposures (plus one foreground...

The Antikythera Mechanism
9.01.2011

What is it? It was found at the bottom of the sea aboard an ancient Greek ship. Its seeming complexity has prompted decades of study, although some of its functions remained unknown. Recent X-rays of the device have now confirmed the nature of the Antikythera mechanism, and discovered several surprising functions.

On a Blue Moon
1.09.2012

Rising at sunset, the gorgeous Full Moon of August 31 became the second Full Moon in a month. According to modern reckoning, that makes it a Blue Moon. In fact, parts of the Full Moon do look a little blue in this sharp lunar portrait.

Aurora and Unusual Clouds Over Iceland
18.11.2013

What's happening in the sky? On this cold winter night in Iceland, quite a lot. First, in the foreground, lies the largest glacier in Iceland: Vatnajokull. On the far left, bright green auroras appear to emanate from the glacier as if it was a volcano. Aurora light is reflected by the foreground lake JЖkulsАrlСn.

Electric Night
4.12.2019

It may appear, at first, like the Galaxy is producing the lightning, but really it's the Earth. The featured nighttime landscape was taken from a southern tip of the Italian Island of Sardinia in early June.