All the planets rotate anticlockwise, except one
All the planets in the solar system rotate anticlockwise, except one. Venus is the only planet that rotates clockwise. Venus (radius 3,760.4 miles) is similar to Earth (radius 3,963.19 miles) in size and structure but spins very slowly; a day on Venus is 243 Earth days long.
Venus is the second planet from the sun, our closest planetary neighbor and, with a radius of 3,760 miles (6,052 kilometers) similar in structure and size to Earth.
Its thick atmosphere traps heat in a runaway greenhouse effect, making it the hottest planet in our solar system with surface temperatures hot enough to melt lead. Glimpses below the clouds reveal volcanoes and deformed mountains.
Venus infrared light photo by ISAS/JAXA Japan Space Agency Akatsuki spacecraft
Venus is named for the ancient Roman goddess of love and beauty, the counterpart to the Greek goddess Aphrodite.
Venus significant dates
The NASA Venus page provides very interesting significant dates about Venus:
- 650 BCE: Mayan astronomers make detailed observations of Venus, leading to a highly accurate calendar.
- 1610: Galileo Galilei documents the phases of Venus in The Starry Messenger.
- 1639: The first predicted transit of Venus is observed in England.
- 1761-1769: Two European expeditions to watch Venus cross in front of the sun lead to the first good estimate of the sun’s distance from Earth.
- 1961: Radar returns from Venus are used to determine the most accurate value (at the time) for the sun’s distance from Earth. (Published in 1962.)
- 1962: NASA’s Mariner 2 reaches Venus and reveals the planet’s extreme surface temperatures. It is the first spacecraft to send back information from another planet.
- 1970: The Soviet Union’s Venera 7 sends back 23 minutes of data from the surface of Venus. It is the first spacecraft to successfully land on another planet.
- 1990-1994: NASA’s Magellan spacecraft, in orbit around Venus, uses radar to map 98 percent of the planet’s surface.
- 2005: The European Space Agency launches Venus Express to study the atmosphere and surface. The orbiter reached Venus in April 2006, and studied the planet through 2014.
- 2015: After launching in 2010, Japan’s Akatsuki (“Dawn”) orbiter achieves orbit around Venus.
The others and us
It’s easy to remember the order of the eight planets with this line: My Very Eager Mother Just Served Us Nachos. The capital letters stand for the order of the planets, starting closest to the sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
Earth is the densest (5.515 g/cm3) planet in the solar system and the only one not named after a god.
Earth orbits the sun at an average speed of 66,629 mph (107 229 km/h). One year on earth is 365.24 days long. One day is 23 hours, 56 minutes and 4,06 seconds long. The extra day in a leap year was introduced to compensate for the discrepancy in the Gregorian calendar.
And remember too, that earth is not completely round; it is slightly pear-shaped. The North Pole radius is 44mm longer than the South Pole radius.