Table of Contents
How does the Big Dipper sometimes appear upside down?
The Big Dipper sometimes appears upside down because of Earth’s rotation. As Earth rotates, the Big Dipper appears to circle around the sky near the North Star, causing it to appear at different angles to us on the ground.
How do you use the planisphere?
Hold the planisphere in front you like a reading book. Rotate it so that ‘south’ on the planisphere is pointing towards the southern horizon you’re facing. Make a note of your zenith view ((overhead) and compare to the planisphere. Now compare the southern horizon view with the planisphere.
What causes the change in orientation of the Big Dipper?
ANSWER: The Big Dipper sometimes appears upside down because of the Earth’s rotation. The Earth’s axis points to the North Star, Polaris. That causes the orientation of the Big Dipper to change from season to season.
How does the Big Dipper move?
The only thing that makes our sky clock different from the ones we have in our home (or around your wrist) is that the Big Dipper moves around Earth’s geographic North Pole in a counterclockwise direction.
How do you use the Big Dipper to find other constellations?
The Big Dipper rotates around Polaris. To find Polaris, mentally draw a straight line connecting the two stars on the far side of the bowl of the dipper, extend it five times, and you will arrive at Polaris. Polaris is at the end of the handle of the Little Dipper.
What is planisphere used for?
A planisphere is a type of star chart that can be set to show the location of objects in the sky for any given date and time. It is small, portable and easy to use, providing a very convenient tool for identifying objects seen in the sky, or locating specific objects of interest.
Why might you need a planisphere to help determine which constellation are visible?
A planisphere is a rotating star locator. It’s a virtually indispensable tool for beginning stargazers. At the drop of a hat, the stars and constellations on the planisphere instantly match those in the real sky.
How does the position of the Big Dipper change during the year?
This apparent motion is caused by Earth’s daily rotation on its axis. As students use their Dipper Clocks, they will see that the position of the Big Dipper changes both with time of night and with time of year. This second and slower change is caused by Earth’s revolution around the Sun in its yearly orbit.
Is the Big Dipper always visible?
Since the Big Dipper is a circumpolar asterism (from our latitude of about 42° north), all of its stars are visible regardless of the time of night or time of year, assuming you have a clear northern horizon.