We live on a water world roughly 8000 miles in diameter sandwiched about mid-way between the orbits of Venus and Mars and about 93,000,000 miles from Sol (a yellow white star that we call the sun). Some of our nearest neighbors have been a source of wonderment and interest among star gazers for centuries. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Nine tiny planets in a vast universe. We hope you will find our descriptions of the planets and the graphic images that we got from the Calvin J. Hamilton's Solar System Homepage, interesting. If this information interests you just click on each image and you will be wisked away to the planet page of your choice.
Please excuse our Geocentric point of view, but after all...it is home.
Closest to the Sun is Mercury. Mercury is roughly 36 million miles from the sun and 3100 miles in diameter, the smallest planet in the solar system. The Mercurian day is 59 earth days long and its year is 88 earth days long. So a year on Mercury is equivalent to 1 1/2 mercurian days in length. The temperatures on Mercury range from 950 F to -346 F, making Mercury a very unlikely place for human or other life form habitation.
Venus, 67 million miles from the sun and 26 million miles from earth. Venus is similar in size and gravitational pull to the earth at 7600 miles in diameter and 87% of Earth's gravity. But that's where the similarity ends. Conditions are hellish on Venus with temperatures up to 900 F and pressures over 3000 lb per square inch (that's 20 times the pressure here on Earth!) on the surface. Venus' atmosphere is composed of carbon dioxide and sulfuric acid, a decidedly unpleasant mixture. So, for the time being, we'll still have to admire Venus as the brightest "star" in the evening and morning sky, from here at home on earth.
Our near neighbor, Mars a "world that might have been" is believed to have once has liquid surface water. Running water could be responsible for the erosion that we see with our spacecraft. The Martian day is 24.6 hours long. At its closest point, Mars is 34.6 million miles from Earth. Gravity on Mars is about 38% of that on earth. Being nearly 50,000,000 miles farther from the sun than we are, Mars is a rather chilly and inhospitable place. But it might be possible to someday terraform Mars. Many have considered Mars to be the best candidate in the solar system for a human colony. What do you think?
Beyond Mars are the asteroids and the outer planets. Jupiter, is the largest planet, a banded gas giant at 88,900 miles across the equator. Jupiter is known to have 16 moons. At 318 times the mass of earth, it's only 1/4 as dense. The Jovian day is approximately 10 hours long, whirling at 22,000 miles per hour, causing Jupiter to have a flattened appearance at its poles and a bulge at the equator. Jupiter is believed by many to be a "failed star" due to the fact that it radiates away almost twice as much heat as it absorbs from the sun. If Jupiter possessed just slightly greater mass and its core was compressed just a bit more, we could be living in a two star system. The atmosphere of Jupiter is mostly Hydrogen, Helium, Ammonia, Methane, Ethane, Acetylene and many other equally noxious compounds.
Saturn, the ringed world. Saturn is another gas giant, 75,000 miles across. It is made up of mostly Hydrogen and Helium gas. Saturn is one of the least dense planets in the solar system. Saturn, like Jupiter spins on its axis at a ferocious speed, giving it its "squashed" appearance. Its day is just a little over 10 hours in length. Saturn is known to have at least 20 moons. Solid water (ice) has been discovered on five of Saturn's satallites. Saturn's largest moon, Titan, is 3200 mile diameter. Titan has an atmosphere and some scientists believe that primitive life forms on Titan are a distinct possibility. Saturn's stupendous rings are composed of mostly rocks and chunks of ice forming very thin layers. They are believed to have formed from the remains of a small planetoid that passed too close to the planet and was torn apart by the overwhelming force of the main planet's gravitational pull.
Uranus is the "planet who fell over on its side", the axis being almost horrizontal. It orbits the sun on its edge. This giant blue/green planet is almost 4 times the size of earth. Uranus sports 11 concentric rings composed of ice, dust and rocks and has 15 known moons. Most of the moons are frozen masses of rock and water ice. By all accounts at -350 F, Uranus should be a dark planet. However, it has been found to emit a strange blue "electroglow" --as yet unexplained by scientists.
Neptune was known for many years to be a frozen ice ball. Because of Voyager and the Hubble Space Telescope we now know this blue giant (appriximately 4 times the size of earth) to be dynamic. It has violent storm systems that make the worst hurricane on earth look like a spring shower by comparison. Neptune has strong magnetic and electric fields. These create spectacular auroras, similar in nature to the Northern and Southern lights on our planet. Neptune is known to have 8 moons, one of which, Triton, has been discovered to have volcanic eruptions of dust, nitrogen gas, ice and rock. The temperature on Triton has been measured at -391 F, the coldest ever measured of any body in space.
Pluto, a tiny planet (at 1430 miles in diameter),nearly 3.7 billion miles from the sun marks the end of the solar system. Scientists believe that there may be yet another planet 50 billion miles out beyond Pluto. Pluto appears to have a thin atmosphere of methane (quite a feat for a planet believed to be -451 F at the surface). Pluto's orbit crosses the orbit of Neptune periodically. This causes the two planets to alternate as the outermost planet from the Sun. A Plutonian year is equivalent to 248 earth years, longer than the entire history of the United States. Pluto has a single moon named Charon. Some scientist believe that Pluto is a large comet which was captured into a planetary orbit. Charon may be another comet, or a piece of Pluto that broke off and went into orbit around it.
We hope you enjoy the images of the solar system that we have provided on this page and we hope that this will encourage you to look for further information about the planets, the solar system and about all kinds of space stuff.
We are big supporters of NetDay96 a set of activities to provide internet access in the schools. It would be wonderful if you could volunteer your time or provide sponsorship in the way of cash, material or expertise to a local school. Our school had a big kickoff day on Saturday, March 9. We're off and running! Visit the NetDay96 site and let them know what you think.
Our main reference document for the information and the quotes contained on this page is "A Journey Through Time, Exploring the Universe with the Hubble Space Telescope" by Jay Barbree & Martin Caidin. Many more wonderful images can be found at The NASA Photo Gallery or at Solar System Homepage
Our graphic images of the planets were obtained from the Solar System Homepage and we highly recommend paying them a vist to see more great stuff.
Our Background graphics were obtained from Mudrider.,Kai's Backgrounds Archiveand Chris's background page
This page was created and is best viewed when using Netscape version 1.2 or above.
Special thanks to Jim Glass for his undying patience, his editorial skill, his lists of science fiction and Mike Oldfield stuff and (this is important) the use of the scanner.
Thanks to Earthlink, my internet service provider, for making server space available for this page.
This page was created on March 30, 1996 by Sandy Stoller