If conditions are calm, then a bowl of water will suffice. Measurement are made between the direction of the real Moon and it's mirror image reflected off the liquid surface. The sextant angle which is observed is twice that of the required altitude h of the Moon before index error and error of refraction are applied. The Earth's atmosphere causes light from any heavenly body to be refracted or bent. The error introduced by this effect can be as large as 1 degree of arc, but formulae do exits to compensate for its effect.
Main Procedures Look for a suitable partner school.
A and B should be as large as possible. The difference between geographical longitudes should not be too great, otherwise simultaneous visibility could be a problem. Record the latitude and longitude of the locations where the observations will take place. This information is used to calculate the angle F Make arrangements with your partner to determine suitable times for simultaneous measurement. Record the date and take simultaneous measurements.