The Earth's atmosphere is home to some gorgeous phenomena... it's just difficult to capture on film. Take, for instance, so-called "noctilucent" clouds — NASA had to fly a giant balloon into the sky, over 80km high, to get its images. Six million shots, in fact, and NASA has only just started sifting through them.
Image: Kevin Cho
Noctilucent clouds, also called "polar mesospheric clouds" (PMCs), can be found at Earth's poles during winter or summer (depending on the hemisphere). In order to better study the phenomenon, NASA, as part of its PMC Turbo project, used a balloon equipped with "seven specially designed imaging systems", each packing a camera and 32TB of storage.
While the balloon didn't max out this space, it did collect a whopping 120TB — a great deal of it being PMC displays, according to NASA:
"From what we've seen so far, we expect to have a really spectacular dataset from this mission," said Dave Fritts, principal investigator of the PMC Turbo mission at Global Atmospheric Technologies and Sciences in Boulder, Colorado. "Our cameras were likely able to capture some really interesting events and we hope will provide new insights into these complex dynamics."
Sweet... but what are PMCs, exactly? Well, here's what they look like in motion.
And here's an explanation, courtesy of NASA:
Noctilucent clouds coalesce as ice crystals on tiny meteor remnants in the upper atmosphere. The results make brilliant blue rippling clouds that are visible just after the Sun sets in polar regions during the summer [in the northern hemisphere].
These clouds are affected by what’s known as atmospheric gravity waves — caused by the convecting and uplifting of air masses, such as when air is pushed up by mountain ranges. The waves play major roles in transferring energy from the lower atmosphere to the mesosphere.
They're also stunning to look at, but that's probably a less important fact on the science front.