Solution: Make sure that you are connected to the internet when running SkySafari for the first time.

If this does not work try these tips:

1. Disconnect from your WiFi. Then reconnect.
2. Try rebooting your device. Try the download again.
3. Log out of Google Play. Then log back into your account. Try the download again.
4. just waiting 24-48 hours before trying the download again can resolve the issue at times.