Astronomy Terms

Fun Facts About Astronomy Terms

• Eclipse during a total lunar eclipse, Earth's atmosphere bends red sunlight toward the Moon, projecting onto its surface all the world's sunsets and sunrises. This gives the moon a striking coppery-red color, turning it into a "Blood Moon".
• Equinox it's when the Sun is directly over the equator, causing it to rise due east and set due west everywhere on Earth. This means the day and night are almost exactly equal in length (about 12 hours each).
• Galaxy our Milky Way galaxy is so huge that it takes the Sun about 230 million years to complete one full orbit around its center. The dinosaurs went extinct less than one galactic year ago (66 million years ago).
• Light-Year it's not a measure of time but of distance. Light travels at 186,000 miles per second, so in one year it covers roughly 6 trillion miles. The nearest star (besides the Sun) is over 4 light-years away from Earth.
• Meteor what most of us call "shooting stars" are no bigger than a grain of sand before they burn up in Earth's atmosphere, at speeds up to 45 miles per second, in a dazzling light show.
• Planet the word comes from the ancient Greek for "wanderer", because ancient skywatchers observed how they slowly moved against the relatively fixed background of stars.
• Solstice the word literally means "Sun standing still", aptly describing how the Sun appears to pause at its northernmost or southernmost point in the sky before reversing direction. This marks the longest and shortest days of the year.
• Zenith the point directly over your head in the sky (90° above the horizon). It's unique to your exact location, so no two people in different spots on Earth share the same zenith at the same moment.