Earth's solar system is located in the Milky Way, which lies within the Local Group. It consists of a star, the sun, and eight or nine planets depending on the controversial debate whether Pluto is officially a planet, or only a dwarf planet.
The Sun
The sun is a massive ball of gas held together by its own gravitational force. The sun is located at the center of the solar system and contains over 98% of the mass contained in the solar system. The sun's surface, the photosphere, is where most of the sun's radiation is released and detected as sunlight; the sunlight reaches the Earth approximately eight minutes after leaving the sun. Dark spots, known as sunspots, are the darker, cooler regions on the surface of the sun. Every so often, energy that has built up in the solar atmosphere is released, resulting in a bright flash known as a solar flare.
Mercury
The planet closest to the sun, Mercury is only slightly larger than Earth's moon. It is 58 million kilometers away from the sun. Mercury's surface is rocky and cratered, and it can reach a temperature of 800 degrees Fahrenheit. Its orbit around the sun lasts a mere 88 days.
Venus
Venus is second in line from the sun, orbiting the sun from 108 million kilometers away. Her orbit around the sun lasts about 225 Earth days. Venus has a surface that is volcanic and cratered. She also has a backward rotation; the sun rises in the west and sets in the east.
Earth
Earth is the third planet from the sun, and the only known inhabitable planet. Earth lies about 150 million km from the sun and has an atmosphere that is 78% nitrogen and and about 21% oxygen. Earth's moon has a orbit duration of 27 days.
Mars
As the fourth planet, Mars lies 228 million kilometers from the sun and has an orbit duration of 687 Earth days. Mars has two known moon, Phobos and Deimos. Mars is known as the Red Planet, because the soil contains and iron mineral that makes the dusty atmosphere appear red.
Jupiter
Jupiter is the fifth planet from the sun at 778 million kilometers and has an orbit time frame of 11 Earth years. As a gas giant, Jupiter doesn't have a solid surface, although it may have a solid core. While Earth only has one moon, Jupiter has about fifty. She also has a giant red spot on the surface, which has been discovered to be a storm that has been raging for hundred of years.
Saturn
Saturn lies 886 million kilometers from the sun, deeming itself the sixth planet. Saturn's orbit lasts 29 Earth years. Saturn has about the same number of moons as Jupiter, her known moons totaling to 53. Perhaps the planet's most noticeable feature, Saturn is adorned with several rings, made up with thousands of shards of dust, ice, and rock.
Uranus
Uranus is approximately 2.9 billion km from the sun, with an orbit lasting 84 Earth years. Unlike the other planets, Uranus has a sideways rotation, with its equator almost at a 90 degree angle with its orbit. Uranus has methane in its atmosphere, giving it a blue tint. With almost 27 moons, named after characters from the works of Shakespeare and Pope, Uranus isn't far behind Jupiter and Saturn. Uranus has faint rings, and has a west to east rotation like Venus.
Neptune
The eighth planet, Neptune, lies 4.5 billion kilometers from the sun and has an orbit of 165 years. Neptune has constant below-zero temperatures and supersonic winds. She also has 13 confirmed moons, named after Greek mythology.
Pluto
Whether Pluto is actually a planet in our solar system is controversial, it is certainly classified as a dwarf planet. Pluto is the largest of the dwarf planets, and lies approximately 5.9 billion kilometers from the sun. Pluto has a thin atmosphere that expands as it approaches the sun, and collapses as it draws away.
1) Neptune is the closest planet to the sun
Information found on:
- http://solarsystem.nasa.gov/planets/index.cfm
- "Planets." Solar System Exploration. N.p., n.d. Web. 30 Apr. 2015.
- http://solarsystem.nasa.gov/planets/index.cfm
- "Planets." Solar System Exploration. N.p., n.d. Web. 30 Apr. 2015.