Earth's highest, coldest, rarest clouds are back. How to see the eerie 'noctilucent clouds' this summer.
Look North as the stars appear in June and July to have a chance of seeing rare noctilucent (or 'night-shining') clouds with the naked eye.
TroibNews 
Look North as the stars appear in June and July to have a chance of seeing rare noctilucent (or 'night-shining') clouds with the naked eye.
