Some thing to try with the Kids in KTP:
Making your own celestrial clock (extract from oneminuteastronomer):
On or about March 29, the Southern Cross stands upright in the southern sky at midnight local time, approximately. Doesn’t matter where you live… Pretoria, Perth, or Palmerston North… at midnight, roughly, as long as you can see it, the Cross will point upright, as in the following image:
Now the stars of Crux, like all stars, will appear to rotate around the south celestial pole during the night (and day). If you face south, Crux will rotate clockwise at half the rate of the hour-hand in a clock. In 24 hours, Crux comes all the way around to its original position. In 6 hours, Crux makes a quarter revolution, and in 3 hours, it makes ⅛
of a revolution, and so on. So, as an example, on March 29 you look up and see Crux pointing to 1:30 on its celestial clock, you know it’s 3 a.m. refer to the image below:
If it’s pointing to 3:00 on March 29, then it must be 6 a.m. And if it’s pointing to 11:00, then it must be 10 p.m.
You can use the same trick at other times of year, assuming you can see Crux from your location. But it’s a little more complicated because Crux will point to midnight at a time other than true midnight. That’s because the stars shift a little in position each night because of the Earth’s revolution around the Sun. In a month, the stars rise earlier by 2 hours. So Crux points directly upward to 12:00 at 10 p.m. on April 29, and 8 p.m. on May 29, and 2 a.m. on February 28 (or March 1), and so on.
Just remember, add 2 hours for each month after March 29, or subtract 2 hours for every month before March 29. That works out to one hour every two weeks.
That’s how to make your very own celestial clock. It’s not as accurate as your Timex or Rolex, but it’s far more fun. Try with your kids in KTP.