Ever since Galileo confirmed the earth was not the center of the universe, man has been pushing the limits of knowledge to discover more about the universe and in particular the solar system. With the technological advancements of the past century, man has been able to discover more about the solar system then in the previous thousand years combined. the solar system is comprised of the Sun, planets, dwarf planes, asteroids, comets, moons and other items of interest briefly discussed below.
– The Sun
The Sun is the yellow star at the center of the solar system that provides the heat and light to allow life on earth. It makes up 99.8 percent of the total mass of the solar system and could hold 109 Earths inside itself. The surface of the sun is 10,000 degrees Fahrenheit (5,500 degrees centigrade), at its core the temperature is 28 million degrees Fahrenheit (15.5 million degrees centigrade). All objects in the solar system orbit the sun.
– Inner Planets
Mercury is the first planet from the Sun and its daytime temperature can reach 800 degrees Fahrenheit (430 degrees Celsius). Mercury is heavily cratered and has no atmosphere, without an atmosphere to hold in the heat at night temperatures plummet to -280 degrees Fahrenheit (-170 degrees Celsius). Mercury is the smallest full planet in the solar system now that Pluto has been downgraded to a dwarf planet status.
Venus is the second planet from the Sun and similar size to earth. It is one of the brightest objects seen with the naked eye in the night sky. Venus has a thick toxic atmosphere consisting of carbon dioxide, sulfuric acid, and a small amount of water. Since Venus has a thick atmosphere it holds heat well, the temperature reaches 880 degrees Fahrenheit (470 degrees Celsius).
Earth is the third planet from the Sun. It is comprised of 70 percent water and sustains life. Earth has an atmosphere that is 78 percent nitrogen, 21 percent oxygen and 1 percent other items. The atmosphere acts as a protective shield by blocking radiation from the sun and space, as well as burn up meteorites before they can strike the ground. The earth has many features into which this brief overview will not delve.
Mars is the fourth and last planet in the inner solar system also, known as the red planet. Billions of years ago it was thought that mars had running water, and to have had the biggest flood in the solar system. The flood carved the channels that mark the Martian landscape and are visible from earth, with even a crude telescope. Currently the atmosphere is too thin and the temperature is too cold to allow liquid water. Water is now frozen near the surface and in concentration at the polar ice cap, but not enough water to have caused that ancient great flood. That is a mystery that is still under investigation.
– The Asteroid belt
The asteroid belt divides the inner solar system from the outer solar system. So far around 90,000 asteroids have been discovered in the belt; common belief is that they are the remains of a failed planet. Recently one of the asteroids has been elevated to dwarf planet status, its name is Ceres. Ceres is one quarter the size of earth. Some scientists believe that 65 million years ago an asteroid slammed into Earth killing off the dinosaurs and changing history. Some fear this could also happen in the future and eliminate life on the planet as man knows it.
– Outer Planets
Jupiter is the fifth planet from the sun and the largest. Jupiter is a gas giant type planet, which some scientists describe as a failed star. The atmosphere consists of mainly hydrogen and helium. Jupiter has one distinguishing feature, the great red spot. The great red spot is a giant storm that has been observed for as long as 300 years. Jupiter has a great gravitational pull that also helps protect the earth by steering meteorites and rogue comets into it, where they burn up. Jupiter has 63 known moons with four large enough to be seen with a crude telescope. Ganymede is the largest and is bigger than Mercury, it would be considered a planet if it orbited the Sun instead of the moon.
Saturn is the sixth planet from the Sun and is most known for its rings. Saturn is a gas planet similar to Jupiter; it is comprised mostly of hydrogen and helium. The rings of Saturn are hundreds of thousands of kilometers wide. There is a division in the rings and there is an A and B ring, the division is roughly 3000 miles wide. Saturn was the furthest planet seen by the ancients with their crude telescopes.
Uranus is the seventh planet from the Sun. Uranus is a blue green gas giant planet whose color is derived from methane in its atmosphere. The atmosphere is also comprised of hydrogen, helium, ammonia and water molecules. Uranus is rotates on an odd axis, it rotates horizontally, some think this is due to being hit in the past by a planet sized object. Uranus is so far from the sun, that even though it has an atmosphere its temperature is -357 degrees Fahrenheit (-216 degrees Celsius).
Neptune is the eighth planet from the sun and the last full size planet. Neptune is the furthest gas giant planet and has storms similar to Jupiter’s great red spot that move across the atmosphere constantly. The storms on Neptune are three times stronger than Jupiter’s storms and nine times stronger than the worst storm on earth. The atmosphere is also comprised of hydrogen, helium, ammonia and water molecules and gains its blue color from the methane like Uranus.
Pluto is the ninth planet from the sun, yet it has lost its status as a full planet and is now considered a dwarf planet. Pluto, Ceres and Eris are the known dwarf planets in the solar system. Pluto is comprised of a mixture of frozen nitrogen, methane, and carbon monoxide ices. It is 3.7 billion miles from the Sun and its temperature is -356 degrees Fahrenheit (-215 degrees Celsius).
Eris is the tenth planet but it is not a full planet, it is the largest of the Dwarf planets. Eris is similar to Pluto in its makeup.
Trans-Neptunian objects are object further out in the solar system than Neptune. These objects include Pluto, Eris, Makemake, Haumea, The Kuiper belt, scattered disk, Oort cloud and Sedna. You can click on the Trans-Neptunian link at the beginning of this paragraph for more information on these objects.