Step by step
Step 1
Download lunar occultation prediction software such as Occult v4. Input your location details and a date range to get a list of occultations specific to your location. Astronomy publications and local and national astronomical societies can also help.
Step 2
Choose which lunar occultations to observe. Determine where on the lunar limb the star will make its disappearance and reappearance. Disappearances on the dark limb are easier to gauge, as you watch the star as the Moon moves ever closer.
Step 3
Check the location you are observing from and make sure you can see the Moon at the time of the event. Set up your equipment. Make sure you are familiar with moving it steadily (if it is not motorised) and practice using your stopwatch.
Step 4
Observe the occultation. Make sure you watch the star as it moves towards the Moon during a disappearance, or that you are observing the area of the lunar limb where the star should make its reappearance, as the limb itself won’t be visible if it’s in shadow.
Step 5
Start your stopwatch as soon as you see the star disappear. Then, looking at an accurate clock, stop the stopwatch, noting the precise time. Deduct the stopwatch time to pinpoint the start of the event at your location. This also works for the reappearance.
Step 6
Record the details of the event either for yourself or to send to the relevant bodies, such as IOTA, if required. As the software predicts an event time, you may find that there is a difference to the time that you observed the occultation.