The zodiac is an area of the sky that extends approximately 8° north or south (as measured in celestial latitude) of the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year. The paths of the Moon a...

The Julian calendar was introduced by Julius Caesar in 45 BC. It was in common use until the 1500s, when countries started changing to the Gregorian Calendar. However, some countries (for example, Greece and Russia) used it into this centur...

The calendar used throughout the world today is the Gregorian calendar. It is sometimes called a "Christian" calendar. The Gregorian calendar is the one commonly used today. It was proposed by Aloysius Lilius, a physician from Naples, and a...

Guillaume Le Gentil was a French astronomer. He discovered what are now known as the Messier objects M32, M36 and M38, as well as the nebulosity in M8, and he was the first to catalogue the dark nebula sometimes known as Le Gentil 3 (in the...

The Roswell UFO Incident involves the recovery of materials near Roswell, New Mexico, USA, on July 8, 1947, which since the late 1970s has become the subject of intense speculation, rumor, and questioning. There are widely divergent views o...

Sputnik 1 or Elementary Satellite-1 was the first artificial Earth satellite. It was a 58 cm (23 in) diameter polished metal sphere, with four external radio antennas to broadcast radio pulses. The Soviet Union launched it into an elliptica...

Apollo 11 was the spaceflight that landed the first humans on the Moon, Americans Neil Armstrong and Buzz Aldrin, on July 20, 1969, at 20:18 UTC. Armstrong became the first to step onto the lunar surface six hours later on July 21 at 02:56...

The Voyager Golden Records are two phonograph records that were included aboard both Voyager spacecraft launched in 1977. The records contain sounds and images selected to portray the diversity of life and culture on Earth, and are intended...

Mars One will establish a permanent human settlement on Mars. Crews of four will depart every two years, starting in 2024. Our first unmanned mission will be launched in 2018. Join the Global Mars One Community and participate in our missio...