Others Like “A Model of Gravity in Our Solar System” (top 20 results)

Use your Internet sleuthing skills to learn about solar system objects. Create a table of measurements of moons and asteroids in order to determine if there is a size threshold for roundness. A good source of information would be an online guide such as The Nine Planets (Arnett, W.A., 2006). You'll find information about planetary satellites, including dimensions and accompanying pictures. From the pictures, classify the satellites and asteroids according to how round they are. Can you think of… Read more

Do you wake up at the crack of dawn, or do you need an alarm clock to wake you up each morning? It may surprise you that the two are not always in synch. Nowadays, we use Standard Time to set our watches instead of Solar Time. Which method of timekeeping is the most accurate? Get ready to synchronize your watches! Timekeeping is the science of how to keep time with precision and accuracy. People have been finding ways of measuring time for thousands of years, usually based on the movements… Read more

You can measure the diameter of the Sun (and Moon) with a pinhole and a ruler! All you need to know is some simple geometry and the average distance between the Earth and Sun (or Moon). An easy way to make a pinhole is to cut a square hole (2-3 cm across) in the center of a piece of cardboard. Carefully tape a piece of aluminum foil flat over the hole. Use a sharp pin or needle to poke a tiny hole in the center of the foil. Use the pinhole to project an image of the Sun onto a wall or piece… Read more

Let's suppose you can take advantage of the Internet and get a 'pen pal' located a 1000 miles away in another city. On the same night, and at EXACTLY the same time 'Universal Time', make a CAREFUL observation of where the Moon is located with respect to the background stars. You should be able to discern a slight (about 1/2 the Moon's diameter) shift in position due to parallax. Then, with a little geometry, you could estimate the distance of the Moon during the full lunar cycle (Odenwald,… Read more

Some claim the Moon appears larger when near the horizon. Make a series of observations of the Moon, measuring the Moon's angular diameter each time. You should also note the Moon's altitude above the horizon, and the Moon's phase. You should do background research on the lunar orbit to determine the necessary time period. Do you find predictable variations in the Moon's diameter? Can you relate this to the Moon's changing distance from Earth? From your data, try to determine when apogee and… Read more

Get good photographs of the Moon showing lots of craters and count how many craters you find in a range of diameter classes. One useful source is the Consolidated Lunar Atlas (Kuiper et al, 2006). Make a histogram that shows the distribution of diameters. Most of these craters were formed during the first billion years of the Moon's formation, but you should confirm that this is true for the the Moon areas you've selected in your photographs by doing background research. Is cratering uniform… Read more

The Transiting Exoplanet Survey Satellite (TESS) is a space telescope for NASA's Explorers program, designed to search for exoplanets using the transit method in an area 400 times larger than that covered by the Kepler mission. It was launched on April 18, 2018 atop a Falcon 9 rocket. During its two-year primary mission, it was expected to find more than 20,000 transiting exoplanets, compared to about 3,800 exoplanets known when it launched. The first light image from TESS was taken on August… Read more

Make a pinhole projector (see Measuring the Diameter of the Sun and the Moon). Use the pinhole to project an image of the Sun onto a wall or a piece of paper. Do you notice any dark spots on the projected image? Trace the projected image and count the dark spots. Use your pinhole projector to make images of the Sun at the same time of day for several consecutive days. How does the pattern of spots change? Can you use your data to figure out how fast the Sun rotates? Sunspot activity rises… Read more

Saturn is a unique planet because of the many beautiful rings surrounding it. How are all of those rings made? Why is each ring unique? Read more

In astronomy, a transit (or astronomical transit) is a phenomenon when a celestial body passes directly between a larger body and the observer. As viewed from a particular vantage point, the transiting body appears to move across the face of the larger body, covering a small portion of it. The word "transit" refers to cases where the nearer object appears smaller than the more distant object. Cases where the nearer object appears larger and completely hides the more distant object are known as… Read more