The Planets in Our Solar System

There are currently eight planets in our solar system. (Previously, nine before 2010, when it was determined that Pluto was not a planet, but a massive body revolving around our sun).

Planets of Our Solar System

Designated as the smallest planet in our solar system, Mercury is the closest planet to the sun at a distance. Only 36 million miles or 0.39 AU.  Mercury orbits the sun every 88 Earth days. (The closer the planet is to the Sun, the faster it revolves around it). Mercury’s has a thin atmosphere. We could not survive in this atmosphere. In 1974 , two spacecraft visited Mercury: Mariner 10 and MESSENGER. Learn More.

Second planet from the sun and slightly smaller than Earth. It revolves around the sun every 225 Earth days. Over 40 spacecraft have explored Venus. Notably, Magellan which mapped over 98% of the planet’s surface. The planet’s temperatures can go up to 480 degrees. Venus is unusual as it spins backwards, resulting in the sun rising in the west and setting in the east.

Earth, the third planet from the sun at a distance. It is 93 million miles or one AU (hence the AU designation and reference). Earth is at the right distance to sustain an abundance of life, including intelligent life. Not too close, like Venus. Not too far like Jupiter. A perfect setting for life as we know it.

Mars is the fourth planet from the sun at a distance 142 million miles or 1.52 AU. Mars makes a complete orbit around the sun in 687 Earth days/ There are two moons orbiting Mars. Phobos and Deimos. It it believed that Mars once sustained life many years ago and we are still searching the planet with the Mars Voyager program to determine just that. If confirmed, scientists can then determine that Earth is not the only planet that can sustain life.

The largest of the 8 plants. If Jupiter was a soccor ball, Earth would be a pea in comparison. Jupiter is about (484 million miles, 5.2 AU. Jupiter makes a complete orbit around the sun every 12 Earth years. Known as the ‘gas-giant’, it has not solid surface and imagine landing on Jupiter with no solid surface! There are 50 moons revolving around this planet. Jupiter is know for its Great Red Spot. A gigantic storm of immense proportions that has been going on since we first discovered Jupiter hundreds of years ago.

Saturn is the sixth planet from the sun (886 million miles, 9.5 AU. Saturn makes a complete orbit around the sun every 29 Earth years.As with Jupiter, Saturn is also a gas-giant with no solid surface.There are 53 known moons revolving abound Saturn. Saturn is probably the most popular plant with its outer rings circling it. The rings, 7 in all are gaseous objects that stay intact from Saturn’s gravitational pull.

Uranus orbits our sun at a distance of about 1.8 billion miles or 19.19 AU. Uranus makes a complete orbit around the sun in about 84 Earth years. Because of the distance from the sun, Uranus is a cold, icy planet. The planet contains 27 moons revolving around it.

Neptune orbits our sun, a star. Neptune is 2.8 billion miles, 30.07 AU from the sun. Like Uranus, Neptune is also a cold (actually colder) planet then Uranus. Neptune has 13 moons. Learn More