• A NASA satellite captured an image of the electric blue noctilucent clouds from space
  • This year's noctilucent cloud season is said to be a 'noteworthy' one, just like last year
  • The phenomenon was first mentioned in 1885, two years after the Krakatoa eruption

A NASA satellite captured electric blue noctilucent clouds over the North Pole. This year's season is said to be an excellent one just like last year.

Noctilucent clouds form in a part of the atmosphere about 30 to 54 miles above the surface of the Earth when water vapor freezes onto specks of meteoric dust, creating the crystals that form iridescent clouds. Often, the seasonal clouds look like silver or electric blue streaks in the sky.

A satellite image shared by NASA Earth Observatory presents a stunning view of these "night-shining" clouds. In the image, the noctilucent clouds can be seen in shades of bright blue and white, with the parts of the clouds that are white representing the clouds with the highest density of ice particles, while the ones in dark blue indicating the lowest density.

The image was taken on June 23 and was created by stitching together data from several orbital passes of NASA's Aeronomy of Ice in the Mesosphere (AIM) satellite.

Noctilucent Clouds
Image: Satellite view of the noctilucent clouds on June 23, 2020. The Image is centered on the North Pole. AIM Satellite/NASA Earth Observatory

Initially, the prediction for the 2020 noctilucent cloud season was for an average one that will not repeat the 2019 season, which was exceptional because the clouds were spotted in the places they don’t usually appear, such as in France, California and Colorado.

However, once the season started in mid-May, it eventually became clear that 2020 was also another good year for noctilucent clouds. In fact, according to NASA Earth Observatory, this year, the clouds were even sighted as far south as Joshua Tree, California.

"When noctilucent clouds extend to mid-latitudes — where people live and notice them on a daily basis — we consider that a noteworthy season," Lynn Harvey of the Laboratory for Atmospheric and Space Physics at the University of Colorado said.

According to Harvey, this was because the conditions were excellent for noctilucent cloud formation this year. Specifically, these clouds need high water vapor and cold temperatures to form, which is why they were often seen in higher latitudes. This year, the mesosphere experienced colder-than-usual temperatures that persisted until June and, there was also extra moisture.

It is unclear why the conditions occurred in these two years year, although Harvey notes the solar minimum or atmospheric circulation patterns as possible causes.

First mentioned two years after the Krakatoa volcanic eruption, noctilucent clouds were once thought to be a rare phenomenon. Today, they are known as a more frequent phenomenon that is linked by many scientists to the increase in greenhouse gas emissions.