Pluto was discovered by Clyde Tombaugh on February 18, 1930 at Lowell Observatory in Flagstaff, AZ. The observatory’s founder, Percival Lowell, had predicted a planet with a mass seven times that of Earth beyond Neptune’s orbit. However, at an apparent magnitude of 15, Pluto was 2.5 magnitudes too dim to be the expected planet. Pluto … [Read more…]
Neptune is the eighth planet of our solar system, named for the Roman god of the sea for its blue color. After Uranus was discovered, observers used Newtonian physics to predict another planet orbiting farther out. French astronomer Urbaine Le Verrier and English astronomer John Couche Adams used the mathematical models of the time to … [Read more…]
The sixth planet out from the sun, Saturn is named for the Roman god of the sowing of seed. Galileo is generally given the credit for discovering Saturn in 1609, but some sources believe that the Assyrians were the first to document observations of Saturn around 700 B.C. They called it the “Star of … [Read more…]
The second most massive object in the solar system and most massive of the planets, Jupiter was named for the Roman king of the gods. Its cloud belts and four largest moons can be seen using a small telescope. Jupiter and the other Jovian planets are occasionally referred to as "gas giants," a misnomer since … [Read more…]
Named after the Roman god of war, Mars is also often referred to as the “Red Planet.” It is a favorite among science fiction writers and stargazers. As an interesting note, Mars was the Roman god of agriculture before becoming associated with the Greek god Ares. Those in favor of terraforming and colonizing Mars … [Read more…]
Often called “Earth’s twin” or “Earth’s sister planet,” Venus is the terrestrial, or rocky, planet that is closest to Earth in size, gravity, and composition. It can be seen in the sky shortly after sunset or before sunrise and is typically one of the first “stars” to appear. For this reason, it is called the … [Read more…]
Named for the fleet-footed messenger of the gods, Mercury is the innermost planet of the solar system. If you have a good eye or a telescope, you can usually see it right after sunset or right before sunrise. (It’s dimmer than Venus and usually a bit lower in the sky.) Because it is closer to … [Read more…]
Earth. You might think of your home planet in terms of where you’re living right now, or in terms of exotic landscapes like deserts, rain forests and the glaciers of Antarctica. It’s constantly changing and moving pretty fast, to the tune of 66,660 miles per hour in our solar orbit. How often do you think … [Read more…]
The U.N. General Assembly has declared April 12th the International Day of Human Space Flight. Why this day? Well, on April 12, 1961, a Russian cosmonaut named Yuri Gagarin was launched on a single orbit around Earth. It was an important breakthrough and one in a series of Space Race firsts on the Russian side. … [Read more…]
So you want to participate in a triathlon but that’s a little hard to do when you’re orbiting at an altitude of 370 kilometers. It’s not like the International Space Station has a swimming pool and your favorite athletic activities become a little challenging when you and everything around you are weightless. What should you … [Read more…]