NASA Celestia Guided Activity

Challenge: 2

Use Sunspots to Calculate The Sun’s Spin

To calculate how fast the Sun is spinning around, you will need to watch the Sun from about 2 million kilometers away. Don’t worry, we will put you in the right position. But you will need to play with time and the 'Pause' function a little. If you have printed out your keyboard shortcut list, look at the group titled “Time.”

Sun Spin Recipe for Success

Once you are in position, you will need to speed up time by pressing the “L” key. Every time you press the “L” key, time speeds up by 10 times.
If you want to slow down, you press the “K” key.
When you notice the Sunspots starting to turn, that should be fast enough.
Now if you look at the Date and Time in the upper right corner (make sure that information is there, if there is no text there, you can press the “V” a time or two to make the Date and Time information to appear (and disappear).
Once you find a Sunspot you like, press the Spacebar to PAUSE TIME.
Now you need to do two things, RECORD THE DATE AND TIME (write it down) and put your mouse pointer right on the Sunspot.
Now press the Spacebar again to START TIME. Don’t touch your mouse pointer, just wait for the same Sunspot to come around again.
When the Sunspot is in the same place as when you started, press the Spacebar to PAUSE TIME and RECORD THE DATE AND TIME again.
You will now need to find the difference between these two recordings of yours. It may be a little tricky if you go from one month to another but if you can do it.
Figure out how many days and hours are left in one month and how many days and hours are in the next, then add them together.

Start Year	Start Month	Start Day	Start Hour: Minute

End Year	End Month	End Day	End Hour: Minute

The Sun rotates on its axis (spins!) once every:

days

hours

TIME KEYS
Spacebar	Pause and Un-Pause Time
L	Increase Time by 10x
K	Slow Time by 10x
J	Reverse Time
!	Set Time to Now
\	Start Time (if Stopped)