The view of our planet from space is amazing, but from time to time, the astronauts on board the International Space Station are able to spot an elusive treat - wispy, shining 'polar mesospheric clouds' hanging far above the planet's surface, like these ones spotted above the Ukraine on August 1, 2014.
Polar mesospheric clouds are pretty much what they sound like. They're clouds that happen over the planet's north and south poles, at mesospheric heights, or about 80 to 100 kilometres above the ground. The thin, wispy layer of ice crystals that they're composed of is virtually invisible during the day, when the sunlight is shining down through it. However, as the Sun is setting, and the rays of light from it strike this layer of ice crystals edge-on, the effect is quite spectacular.
Viewed from the ground, the '
ragged edges' of this cloud layer are known as noctilucent clouds - which means 'night shining' clouds - and these have been seen near polar regions going back to the late 1800s. It's not known if they were seen before that, as there are no records prior to 1885, so it may be a recent phenomenon, and it's still being studied to fully understand them. Studies have shown that these clouds could have
an 'extraterrestrial' origin, as dust from meteors streaking through the upper atmosphere may be acting as cloud condensation nuclei. Also, considering that they've been spreading in recent years, and thus are visible much further away from the poles than usual,
NASA notes that some researchers have been investigating whether climate change is responsible, as methane being released into the atmosphere spreads higher and is broken apart to form water vapour.
When spotted from space, they go by their more scientific name. In the image above, they are visible as an extremely thin layer, far above the troposphere (where all of our weather happens). However, closer up, the astronauts caught a much better view of them, showing off the subtle details.
Comment:
Noctilucent cloud intensity is a precursor to changes in global weather patterns. And it should be no surprise that the climate is not at all what it used to be, say 10 years ago. In fact Noctilucent clouds have increasingly become a more ordinary sight at lower latitudes, with the increased fireball and meteor activity in our skies (loading the skies with dust), along with the severe cooling of our upper atmosphere from low solar activity.
Noctilucent outburst over Europe
More cometary dust in the atmosphere: Noctilucent clouds appear above Gateshead in the UK late at night
To get ahead on what our solar system is up to with its ominous weather, read:
Earth Changes and the Human-Cosmic Connection (The Secret History of the World Book 3)