It is almost time for the rarest of clouds to reappear overhead as noctilucent clouds arrive for the summer months ahead.

At this time of year across the Northern Hemisphere, unusual yet incredibly beautiful ribbons of blue and silver clouds light up the nighttime sky well after the sun has set for the day.

Known as Noctilucent Clouds from the Latin meaning “night shining”, these shimmering clouds form at around 50 miles above the Earth’s surface in the mesosphere.

Although it is unknown how these clouds actually form, they are thought to be created from the sun's reflection of ice crystals on dust particles from meteors when temperatures in the mesosphere reach -134°C.

Noctilucent Clouds are primarily visible when the sun sits just below horizon around 90 minutes after sunset or before sunrise between latitudes of 45°N and 80°N in both hemispheres during their summer months.

For us in the Northern Hemisphere, this means we are more likely to witness these incredible scenes between late May and August, while those in the Southern Hemisphere are likely to see them between November and February.

For the best chance, find somewhere free from lower-altitude cloud cover and wait for sunset. As twilight arrives, you may be lucky enough to see the thin, glistening clouds.

Over the next few months, why don’t you see if you can spot any fabulous Noctilucent Clouds where you are? If you do, take a picture and send it into us using the uploader. We would love to see them!