Because moonlight can badly affect your images, we offer significant discounts when observing with the moon above the horizon.

The discounts are based on the moon illumination (100% means full moon, 0% means new moon). The discounts are as follows:

• No discount when observing below the horizon
• 10% discount if you observe with the moon up to 25%
• 25% discount if you observe with the moon up to 50%
• 50% discount if you observe with the moon up to 75%
• 75% discount if you observe with the moon up to 100%

When you use automated scheduling, you can select the preferred moon illumination during the Scheduling step in the New Advanced Request form.

The credit discount will appear on the Request Summary sidebar on the right. Note that our automated scheduler will still schedule your observations at lower moon illuminations if the schedule of the telescope is free, and the discount will still apply!

When using custom scheduling, the discount will be calculated based on the average moon phase during the observing times of your request.

The moon discount in credits will be shown in the request summary during the request submission: