The Prague Astronomical Clock
7.11.2017

In the center of Prague there's a clock the size of a building. During the day, crowds gather to watch the show when it chimes in a new hour. The Prague Astronomical Clock...

Structure in the Tail of Comet 12P/Pons Brooks
16.02.2024

Heading for its next perihelion passage on April 21, Comet 12P/Pons-Brooks is growing brighter. The greenish coma of this periodic Halley-type comet has become relatively easy to observe in small telescopes. But the bluish...

Tycho Brahe Measures the Sky
7.01.2001

Tycho Brahe was the most meticulous astronomical observer of his time. Brahe, who lived between 1546 and 1601, set out to solve the day's most pressing astronomical problem: to determine whether the Earth or the Sun was at the center of the Solar System.

The Mysterious Voynich Manuscript
26.08.2002

The ancient text has no known title, no known author, and is written in no known language: what does it say and why does it have many astronomy illustrations? The mysterious book was once bought by an emperor, forgotten on a library shelf, sold for thousands of dollars, and later donated to Yale.

Cassini Closes in on Saturn
1.03.2004

Are they gone? They were not originally predicted to even be there. The mystery revolves around strange shadow-like spokes that appeared on Saturn's large B-ring, the large middle ring in the complex system of particles that orbits Saturn.

Full Moon, Green Rim
26.08.2005

July's Full Moon looks strangely darkened and distorted in this remarkable telescopic view. The image is one of a series recorded when the Moon was very near the horizon. The long sight-line through...

Comet Hale Bopp Over the Superstition Mountains
9.09.1999

Four years ago, Comet Hale-Bopp was discovered out near Jupiter falling toward the inner Solar System. Two years ago, it provided spectacular pictures as it neared its closest approach to the Sun. Still today, spectacular pictures of the brightest comet of the 1990s are surfacing.

NGC 7293: The Helix Nebula
3.08.2007

A mere seven hundred light years from Earth, in the constellation Aquarius, a sun-like star is dying. Its last few thousand years have produced the Helix Nebula (NGC 7293), a well studied and nearby example of a Planetary Nebula, typical of this final phase of stellar evolution.

Jupiter over Ephesus
18.07.2008

A brilliant Jupiter shares the sky with the Full Moon tonight. Since Jupiter is near opposition, literally opposite the Sun in planet Earth's sky, Jupiter will rise near sunset just like the Full Moon.

Time Lapse Clouds and Sky Over the Canary Islands
16.05.2011

If you could sit back and watch clouds and the sky move all night and day, what might you see? One answer from the island of Tenerife, captured over the course of the year, includes sequences that are not only breathtaking but instructive.