Star Wobble How do astronomers find planets around distant stars? If you look at a star through binoculars or a telescope, you’ll quickly notice how bright the star is, and how difficult it is to see anything other than the star, especially a small planet that doesn’t generate any light of its own! Astronomers look for a … Continue reading "Star Wobble" |
Design a Solar System What would happen if our solar system had three suns? Or the Earth had two moons? You can find out all these and more with this lesson on orbital mechanics. Instead of waiting until you hit college, we thought we'd throw some university-level physics at you... without the hard math. |
Build a REAL Scale Model of the Solar System Ever wonder exactly how far away the planets really are? Here’s the reason they usually don’t how the planets and their orbits to scale – they would need a sheet of paper nearly a mile long! To really get the hang of how big and far away celestial objects really are, find a long stretch … Continue reading "Build a REAL Scale Model of the Solar System" |
Telling Time by the Stars The stars rise and set just like our sun, and for people in the northern hemisphere, the Big Dipper circles the north star Polaris once every 24 hours. Would you like to learn how to tell time by the stars? |
Seasons One common misconception is that the seasons are caused by how close the Earth is to the Sun. Today you get to do an experiment that shows how seasons are affected by axis tilt, not by distance from the Sun. And you also find out which planet doesn’t have sunlight for 42 years. The seasons … Continue reading "Seasons" |
Black Hole Bucket What comes to mind when you think about empty space? (You should be thinking: “Nothing!”) One of Einstein’s greatest ideas was that empty space is not actually nothing – it has energy and can be influenced by objects in it. It’s like the T-shirt you’re wearing. You can stretch and twist the fabric around, just … Continue reading "Black Hole Bucket" |
Advanced Telescope Building So you've played with lenses, mirrors, and built an optical bench. Want to make a real telescope? In this experiment, you'll build a Newtonian and a refractor telescope using your optical bench.Materials:optical benchindex card or white walltwo double-convex lensesconcave mirrorpopsicle stickmirrorpaper clipflash lightblack garbage bagscissors or razorrubber bandwax paperhot glue |
Light, Lasers, and Optics When I was in grad school, I needed to use an optical bench to see invisible things. I was trying to ‘see’ the exhaust from a new kind of F15 engine, because the aircraft acting the way it shouldn’t – when the pilot turned the controls 20o left, the plane only went 10o. My team … Continue reading "Light, Lasers, and Optics" |
Fire & Optics Today you get to concentrate light, specifically the heat, from the Sun into a very small area. Normally, the sunlight would have filled up the entire area of the lens, but you’re shrinking this down to the size of the dot. Magnifying lenses, telescopes, and microscopes use this idea to make objects appear different sizes … Continue reading "Fire & Optics" |
Cosmic Ray Detector When high energy radiation strikes the Earth from space, it’s called cosmic rays. To be accurate, a cosmic ray is not like a ray of sunshine, but rather is a super-fast particle slinging through space. Think of throwing a grain of sand at a 100 mph… and that’s what we call a ‘cosmic ray’. |
Solar Rotation You are going to start observing the Sun and tracking sunspots across the Sun using one of two different kinds of viewers so you can figure out how fast the Sun rotates. Sunspots are dark, cool areas with highly active magnetic fields on the Sun’s surface that last from hours to months. They are dark … Continue reading "Solar Rotation" |
Phases of the Moon The Moon appears to change in the sky. One moment it’s a big white circle, and next week it’s shaped like a sideways bike helmet. There’s even a day where it disappears altogether. So what gives? The Sun illuminates half of the Moon all the time. Imagine shining a flashlight on a beach ball. The … Continue reading "Phases of the Moon" |
Eclipses and Transits It just so happens that the Sun’s diameter is about 400 times larger than the Moon, but the Moon is 400 times closer than the Sun. This makes the Sun and Moon appear to be about the same size in the sky as viewed from Earth. This is also why the eclipse thing is such … Continue reading "Eclipses and Transits" |
Moons of Jupiter On a clear night when Jupiter is up, you’ll be able to view the four moons of Jupiter (Europa, Ganymede, Io, and Callisto) and the largest moon of Saturn (Titan) with only a pair of binoculars. The question is: Which moon is which? This lab will let you in on the secret to figuring it … Continue reading "Moons of Jupiter" |
Jupiter’s Jolts Jupiter not only has the biggest lightning bolts we’ve ever detected, it also shocks its moons with a charge of 3 million amps every time they pass through certain hotspots. Some of these bolts are cause by the friction of fast-moving clouds. Today you get to make your own sparks and simulate Jupiter’s turbulent storms. … Continue reading "Jupiter’s Jolts" |
What’s Up in the Sky? Today you get to learn how to read an astronomical chart to find out when the Sun sets, when twilight ends, which planets are visible, when the next full moon occurs, and much more. This is an excellent way to impress your friends. The patterns of stars and planets stay the same, although they appear … Continue reading "What’s Up in the Sky?" |
Meteorites A meteoroid is a small rock that zooms around outer space. When the meteoroid zips into the Earth’s atmosphere, it’s now called a meteor or “shooting star”. If the rock doesn’t vaporize en route, it’s called a meteorite as soon as it whacks into the ground. |
Retrograde Motion If you watch the moon, you'd notice that it rises in the east and sets in the west. This direction is called 'prograde motion'. The stars, sun, and moon all follow the same prograde motion, meaning that they all move across the sky in the same direction. |
Kepler’s Swinging System Kepler’s Laws of planetary orbits explain why the planets move at the speeds they do. You’ll be making a scale model of the solar system and tracking orbital speeds. Kepler’s 1st Law states that planetary orbits about the Sun are not circles, but rather ellipses. The Sun lies at one of the foci of the … Continue reading "Kepler’s Swinging System" |