The solar system shows a multitude of periodic phenomena: from the daily rotations of the Earth, to the monthly phases of the Moon, the seasonal changes during the course of a year, the phases of Venus and other planets, the regular recurrences of...

The solar system is comprised of the Sun and the celestial bodies which it holds in orbit around it by its gravitational force. The Sun itself makes up 99.8 percent of the solar system's mass, while Jupiter, the largest planet, contains only 0.1...

Earth rotates about its polar axis as it revolves around the Sun. Earth's polar axis is tilted 23.5° to the orbital plane (ecliptic plane). Combinations of rotation, revolution, and tilt of the polar axis result in differential...

Aristarchus (c. 310 B.C.E.–230 B.C.E.), an ancient Greek mathematician and astronomer, made the first claim that the planets of the solar system orbit the Sun rather than Earth. However, it was Nicolas Copernicus (1473–1543) who would...

New observations from NASA's long-running Voyager 2 spacecraft show the solar system is asymmetrical, likely from disturbances in the interstellar magnetic field, scientists reported Monday.The discovery came after the 30-year-old unmanned probe sailed near the edge of the solar system this past summer following its...

The universe really is expanding _ astronomers are proposing to rewrite the textbooks to say that our solar system has 12 planets rather than the nine memorized by generations of schoolchildren. Much-maligned Pluto would remain a planet _ and its...

Detailed observations from the first comet samples returned to Earth are debunking some of science's long-held beliefs on how the icy, celestial bodies form.Scientists expected the minute grains retrieved from a comet Wild 2 to be made up mostly of interstellar dust _ tiny particles...