Facts about Planets

Posted by Admin / in Science Facts Image credit: nasa.gov (all images)

Our solar system has 8 planets that continuously orbit the sun. The Earth is one of the planets. Each planet has a different size, average temperature, length of a year and other differences from the Earth. People from Earth have never visited any other planet, but we have sent spacecraft to other planets to find out more about them. Here are some of the scientific facts we have collected about all eight of the planets.

There are 8 Planets in our Solar System

Mercury

Mercury - 1st Planet from the Sun

Photo credit: nasa.gov

Mercury is the closest planet to the sun in our solar system. In 1974 NASA first photographed the surface of Mercury during the Mariner 10 mission. Mercury's surface is similar to the surface of our moon. There are many craters, some very large in size. Mercury does have an atmosphere, although it is very thin. With almost no atmosphere the temperature of Mercury has a wide range throughout a day. Temperatures can vary almost 1000 °F (330 °C) from day to night. How would you like that weather forecast?

MERCURY FACTS

Length of Year = 88 Earth days
Length of Day = 1407.5 Earth hours
gravity = 12.1 ft/s² (3.7 m/s²)
Typical Temperature = -279 to 801 °F (-173 to 427 °C)
Diameter = 3032 miles (4879 km)
Atmosphere: Very little atmosphere

Venus

Venus - 2nd Planet from the Sun

Photo credit: nasa.gov

Venus is the planet in our solar system most like earth in terms of size and gravity. The atmosphere on Venus, however, is much different than the Earth. The Venus atmosphere is much like a greenhouse. Energy from the sun is absorbed by the Venus atmosphere and the thick cloud cover keeps all the heat inside the atmosphere. At over 850 °F (455 °C), Venus has the highest temperature of any planet in our solar system.

A strange fact about Venus is that its day is longer than its year. Venus spins so slowly on its axis that the planet actually orbits the sun before a day is over.

VENUS FACTS

Length of Year = 224.7 Earth days
Length of Day = 5832 Earth hours
gravity = 29.1 ft/s² (8.87 m/s²)
Typical Temperature = 864 °F (462 °C)
Diameter = 7520 miles (12,103 km)
Atmosphere: Gaseous - Carbon Dioxide and Nitrogen

Earth

Earth - 3rd Planet from the Sun

Photo credit: nasa.gov

The Earth has a temperature and atmosphere that makes it perfect for sustaining life. It is one of the rocky planets, near the sun. Even though the bedrock of the Earth gives the ground surface shape, over 70 percent of our planet's surface is covered by water. To us, the Earth is the center of the universe. The Earth contains the only known life in our solar system or any place in the universe.

EARTH FACTS

Length of Year = 365 Earth days
Length of Day = 24 Earth hours
gravity = 32.2 ft/s² (9.81 m/s²)
Typical Temperature = -353 °F (-214 °C)
Diameter = 7917 miles (12,742 km)
Atmosphere: Gaseous - mainly Nitrogen and Oxygen

Mars

Mars - 4th Planet from the Sun

Photo credit: nasa.gov

Scientists have been interested in Mars for years since many believed that there may be life on Mars. The temperatures on Mars are closest to Earth temperatures, but are still very cold by our standards. Scientists have sent multiple space missions to Mars to collect samples. So far, the missions have not shown that there is life on Mars.

MARS FACTS

Length of Year = 687 Earth days
Length of Day = 24.62 Earth hours
gravity = 12.2 ft/s² (3.71 m/s²)
Typical Temperature = -125 to 23 °F (-87 to -5 °C)
Diameter = 4212 miles (6779 km)
Atmosphere: Gaseous - Argon, Carbon Dioxide, & Nitrogen

Jupiter

Jupiter - 5th Planet from the Sun

Photo credit: nasa.gov

Jupiter is a giant gaseous planet. If Jupiter were empty, approximately 1300 Earths would fit inside. We can recognize Jupiter by its size and the red spot. During the Voyager missions more than 30 years ago, NASA discovered that the red spot is actually a giant storm. Since the red spot is still visible, this storm has lasted a very long time!

JUPITER FACTS

Length of Year = 4333 Earth days
Length of Day = 16.11 Earth hours
gravity = 81.3 ft/s² (24.79 m/s²)
Typical Temperature = -353 °F (-214 °C)
Diameter = 86,881 miles (139,822 km)
Atmosphere: Gaseous - Hydrogen and Helium

Saturn

Saturn - 6th Planet from the Sun

Photo credit: nasa.gov

Saturn is well-known for its large flat rings that orbit the planet. Saturn is a large gaseous planet with a rocky solid core. The planet produces a very strong magnetic field with a strength more than 1000 times greater than the Earth's magnetic field. The strong magnetic field creates a powerful aurora over the polar regions. Wind speed in Saturn's atmosphere is extremely high. The highest wind speeds, at over 1100 mph (1800 km/hr), occur near Saturn's equator.

SATURN FACTS

Length of Year = 10,755.7 Earth days
Length of Day = 10.66 Earth hours
gravity = 34.3 ft/s² (10.4 m/s²)
Typical Temperature = -288 °F (-178 °C)
Diameter = 72,367 miles (116,464 km)
Atmosphere: Gaseous - Hydrogen and Helium

Uranus

Uranus - 7th Planet from the Sun

Photo credit: nasa.gov

Uranus is a large planet that is located far, far away from the warmth of the sun. The distance from the sun and lack of internal heat, results in a very cold planet. Most elements freeze at the temperatures experienced on the surface of Uranus. Scientists believe Uranus has a harsh, gaseous atmosphere.

URANUS FACTS

Length of Year = 30,687 Earth days
Length of Day = 17.24 Earth hours
gravity = 29.1 ft/s² (8.87 m/s²)
Typical Temperature = -357 °F (-216 °C)
Diameter = 31,518 miles (50,724 km)
Atmosphere: Gaseous - Hydrogen, Helium, & Methane

Neptune

Neptune - 8th Planet from the Sun

Photo credit: nasa.gov

Neptune is the furthest known planet to orbit the sun. Its size is a little less than 4 times larger than Earth. With its size and relative mass, Neptune has the second highest gravity of all the planets. Something that weighs 1 pound on Earth weighs 1.14 pounds on Neptune. Neptune's temperature barely warm enough where gases in its air do not freeze so it has a colorful atmosphere.