The sheer vastness and unknown world of space has captivated generations of people as they seek to learn more about this unique and diverse world. Our solar system holds great mysteries even as we learn more about it. As we continue exploring the solar system, consider where it can take us.
THE SUN – OUR SOLAR POWERHOUSE
When you think of our solar system, everything revolves around the sun. It provides our light
and heat here on Earth with all the planets circling this star. Though the sun is a G-type main-sequence star, it holds more power than most other stars in our solar system. The sun keeps the planets in orbit and impacts the gravitational pull of the entire system.
You may wonder how many planets in our solar system are impacted by the sun. Our system is made up of eight major planets and five dwarf planets. Beside these bodies, you have hundreds of moons along with comets, asteroids, and meteoroids.
MERCURY – THE SWIFT PLANET
Mercury is the planet closest to the sun, which makes it a hot place to be. However, there is also ice along the polar regions just like on Earth. Mercury is also the smallest planet but has almost the same surface gravity as Mars. It is known as a terrestrial planet, which means it has a rough and rocky surface. Mercury appears in our sky as a star. Three different spacecrafts have flown by the planet with the latest being MESSENGER from 2008 to 2015. During these explorations, it was determined that craters exist on Mercury’s north pole. Instead of an atmosphere like Earth, Mercury has an exosphere made up of several gases. Potassium was discovered with one of MESSENGER’s missions.
VENUS – EARTH’S TWIN GONE WRONG
Venus is almost as large as Earth, but has no moons. You can often see this planet as a star early in the morning or late in the evening. It spins in the opposite direction from Earth and
has mountains and volcanoes like Earth. Venus is often referred to as Earth’s twin because of the similarities in size and surface. One day on Venus is equal to around 117 days (about four
months) on Earth, but one year on Venus is about the same as 225 Earth days. It’s also the hottest planet in our solar system and only the moon is brighter. Missions to Venus have determined that the planet is inhabitable.
EARTH AND THE MOON – OUR HOME IN THE COSMOS
Earth is unique in the solar system because it is the only planet that can support life. Earth has the correct temperature and atmosphere to allow plants to grow and humans and animals to survive. The moon has a powerful influence on Earth because of its gravitational pull. This gravitational pull causes the tides to rise. NASA has been sending missions to the moon for decades with plans for more manned flights in the next few years. The goal is to eventually build a station on the moon where astronauts can stay during their missions.
MARS – THE RED PLANET
Mars is the fourth planet from the sun and is nicknamed the red planet because of its appearance. Though it has nearly the same landmass as Earth, it has only a fraction of
Earth’s gravity. A year on Mars is almost double the Earth, but it does have a thin atmosphere. However, it is not habitable because the average temperature is -81 degrees Fahrenheit. Scientists have been sending spacecraft to Mars since 1976 with the Viking Landers. These explorations have indicated that a lake may exist under the ice cap at the south pole. They also provide information about the climate and geology of the planet and prepare for humans to explore in the future.
JUPITER – THE GAS GIANT
Jupiter is the fifth planet and has more mass than all other planets combined. You could fit 1,000 Earths in Jupiter, which is made up of gases. It is the third brightest object in the sky and takes nearly 12 years to orbit the sun. What is known as the Great Red Spot has been observed on Jupiter, which is a major storm that has been going on since 1831 or earlier. Jupiter also has 95 moons with some of the moons as large as Earth or larger. Spacecraft have been sent to Jupiter to orbit the planet and gather information. Some experts believe that the moon Europa may harbor some forms of life.
SATURN – RINGED BEAUTY
Next in line to the sun is Saturn, the sixth planet and second only to Jupiter in size. Known for its rings, Saturn is also a gas planet. The rings are made up of mostly of ice with dust and
rocky debris. Saturn also has at least 146 moons, including Titan, which is the largest moon. Scientists believe it could be possible for life to be found on Titan. Missions have included flybys and data gathering. The Cassini-Huygens spacecraft discovered new rings and new satellites with pass-throughs between the planet and its rings.
URANUS AND NEPTUNE – THE ICE GIANTS
The last two of the large planets are Uranus and Neptune. Uranus is a gas giant with a bluish color. It has the lowest temperature at -371 degrees Fahrenheit. Neptune is also an ice planet with a darker blue color. Both planets have a core of rock and ice, mantles of water, ammonia, and methane, and outer atmospheres made up of helium, hydrogen, and methane. Uranus tilts and rotates retrograde where Neptune rotates on its axis like Earth and other planets.
AN EXCITING JOURNEY
From the sun to the moon to all eight planets in between, each body is unique and offers distinct differences. Space exploration is important to help scientists understand what opportunities exist for life in other places. You can learn more about the planets and other bodies as you follow upcoming space missions that are exploring the solar system. Observe the planets in the night sky with a telescope and visit planetariums to learn more about each planet and its role in our solar system!