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ASTR-1020. Introduction to Stellar Astronomy Spring 2014 Solar Rotation Analysis. This is an example. You will need to do a more thorough job and use spots at different latitudes. More measurements will improve your results. Check out the CLEA lab that runs through all this as a guide.
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ASTR-1020 Introduction to Stellar Astronomy Spring 2014 Solar Rotation Analysis
This is an example • You will need to do a more thorough job and use spots at different latitudes. More measurements will improve your results. Check out the CLEA lab that runs through all this as a guide. • CLEA is the Contemporary Lab Exercises in Astronomy from Gettysburg College. The S/W runs in Windows-XP only. • It is due Monday, Apr. 28 at class time. You’ve had all semester to collect data and a month to do the reductions in. No late reports will be accepted! • Do this on your own, not in groups.
Starting with Spaceweather.com Today’s Page This shows today’s Solar image. The numbers identify the spots. Let’s look at spot 1330, it was first visible on Oct. 22 Note the time stamp – Universal Time is used.
Overlay the grid 20111022_144500 ~71 degrees east of meridian
20111028_011500 ~2 degrees west of meridian This spot is also about 2 degrees north Solar latitude
Rough motion calculation • The spot has moved about 73 degrees (71 E to 2 W) • It took 5d 10h 30m (10-22-1445 to 10-28-0115). • A full rotation of the Sun is 360 degrees (plus the Earth’s motion around it during that time). • So 73/360 = 0.2028 if the rotation has occurred in 5.4375 days. • Dividing (5.4375d/0.2028 rot) = 26.8151 days for a full rotation --- at the equator. • Does this seem correct?