Beijing Ancient Observatory
6.05.1998

Did observatories exist before telescopes? One example that still stands today is the Beijing Ancient Observatory in China. Starting in the 1400s astronomers erected large instruments here to enable them to measure star and planet positions with increasing accuracy.

Beijing Ancient Observatory
30.03.2003

Did observatories exist before telescopes? One example that still stands today is the Beijing Ancient Observatory in China. Starting in the 1400s astronomers erected large instruments here to enable them to measure star and planet positions with increasing accuracy.

Europa: Ancient Water World
5.09.1995

Beneath the cold icy surface of Jupiter's moon Europa are probably the only oceans of water in our Solar System outside of Earth. These oceans, possibly 50 kilometers deep, might also be the most likely local place to find extra-terrestrial life.

Stonehenge: Ancient Monument to the Sun
17.12.1997

Stonehenge consists of large carved stones assembled about 4000 years ago. Long before modern England was established, ancient inhabitants somehow moved 25 ton rocks nearly 20 miles to complete it. From similar constructs...

Oklo: Ancient African Nuclear Reactors
16.10.2002

The remnants of nuclear reactors nearly two billion years old were found in the 1970s in Africa. These reactors are thought to have occurred naturally. No natural reactors exist today, as the relative density of fissionable uranium has now decayed below that needed for a sustainable reaction.

Stonehenge: Ancient Monument to the Sun
12.09.1999

Stonehenge consists of large carved stones assembled about 4000 years ago. Long before modern England was established, ancient inhabitants somehow moved 25 ton rocks nearly 20 miles to complete it. From similar constructs...

Oklo: Ancient African Nuclear Reactors
20.02.2005

The remnants of nuclear reactors nearly two billion years old were found in the 1970s in Africa. These reactors are thought to have occurred naturally. No natural reactors exist today, as the relative density of fissile uranium has now decayed below that needed for a sustainable reaction.

Oklo: Ancient African Nuclear Reactors
12.09.2010

The remnants of nuclear reactors nearly two billion years old were found in the 1970s in Africa. These reactors are thought to have occurred naturally. No natural reactors exist today, as the relative density of fissile uranium has now decayed below that needed for a sustainable reaction.

Ancient Layered Rocks on Mars
27.11.2001

Is this a picture of Mars or Earth? Oddly enough, it is a picture of Mars. What may appear to some as a terrestrial coastline is in fact a formation of ancient layered rocks and wind-blown sand on Mars. The above-pictured region spans about three kilometers in Schiaparelli Crater.

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...