There are more and more bright clouds in the night sky, and we now know that they were caused by rockets

Space launches, and more specifically morning space launches, are causing amazing bright clouds to appear in new areas, according to Recent Research Published in the Journal of Earth and Space Sciences.

about 80 kilometers The highest clouds in the Earth’s atmosphere float above the Earth’s surface. calling clouds LaylaOr in the mesosphere or polar atmosphere, these pools of crystallized water vapor are high enough to reflect sunlight, even after sunset or even before sunrise.

Because of their position in the upper atmosphere, when present in time, nocturnal clouds (meaning “glow in the night”) shine with the brilliance of another world. It can make the sky at dusk or dawn resemble the surface of the ocean on a bright day: ripples of silvery light among specks of darkness.

“You see them from “From 30 minutes to an hour and a half after sunset or before sunrise,” he said. Cora Randallan atmospheric scientist at the University of Colorado, Boulder, and one of the researchers on the new study, via video call with Gizmodo. “And that’s because it’s very weak, it’s very thin clouds. You can only see themWhen the sun’s rays are scattered on itIt’s a dark place where you stand. “

TheEmissions from rocket launches, which pump cloud fuel (i.e. water vapor) directly into the intermediate atmosphere, are likely to lead to Making these unique formations even more popular. The launches at the Kennedy Space Center in Cape Canaveral, Florida, could be related to the formation of nocturnal clouds thousands of miles away and days later.

Nocturnal luminous clouds are generally invisible because they commonly form over the poles and occur during summer in every hemisphere. season Night runs from mid-May to August in the north and from mid-November to February in the south. never bipolar It gets darker during the summer, so the luminous night clouds tend to disappear by constant sunlight.

But in recent decades, more luminous clouds have been observed in the so-called “mid-latitudes”, far from the poles, as far as southern California and Colorado. “We’ve noticed that it’s basically gotten brighter and more frequent over the past 50 years or so,” Randall said. Scientists assumed that climate change or solar cycles were to blame.

For the new study, Randall and his co-investigators collected cloud data between 2007 and 2021, which was collected by NASA’s Aeronautics Mesospheric Ice Satellite (AIM). They focused their attention on northern latitudes between 56 and 60 degrees (a narrow strip bounded by Bergen, Norway, to the north, and Edinburgh, Scotland, to the south), where mid-latitude data were more reliable. What they found is that the clouds did not appear to follow any clear direction.

Instead, they note that mid-latitude nighttime clouds are very variable, appearing more often at times but not at other times. Surprisingly, this year-to-year variability closely tracks the pace of morning rocket launches, according to data from NASA’s Mesospheric Ice Aeronautics (AIM) satellite.

The researchers also noted that in the morning, atmospheric winds rapidly carried particles into the middle atmosphere, which is in line with the observed relationship between rockets. yubes Layla. The theory says that water vapor is an emission The rockets are fired in the north direction by the wind Regions of the upper atmosphere that are cold enough to form bright clouds.

The case studies Previous studies have linked luminous nocturnal clouds to emissions from space shuttle launches. However, this is the first research to show that even much smaller missiles seem to have an effect. “The shuttle, of course, is huge compared to some other transport vehicles,” said Michael Stephens, an astrophysicist at the Naval Research Laboratory and co-author of the latest research. “Soand the fact that all small compounds contribute, and Not just contributing, but in a way that drives variation from year to year, It was kind of a surprise. We didn’t expect that.”

Although it is likely not a file missiles. Other factors will likely continue to influence the appearance of nocturnal clouds. Randall identified that climate change almost certainly continues to play a role, even if the data set that she and her colleagues analyzed does not pick up a clear signal. “There is no doubt in my mind that human activities affect clouds. It is really a question of how much in quantitative terms.”

Interestingly, it is believed That there is a relationship between volcanic eruptions and mesospheric clouds for more than a century. The first known recorded case of seeing a night cloud was in 1885, after two years from the eruption of Krakatoa.

But there is a clearer picture of Rocket launch effect It can provide a clearer picture of who we are as human beings Change our planet. Besides being beautifulTo the eye, nocturnal luminous clouds have little known effect here on Earth. Instead, its importance as a potential indicator of man-made change is considered.

The mesosphere and the clouds that appear within it are very sensitive to small changes. If we better understand the impact of missiles, for example, Randall and Stevens said, we can use this knowledge to accurately assess the effects of larger atmospheric disturbances, such as greenhouse gas emissions.

Noctilucent cloud research is also, at its core, an essential expression of human curiosity. “The fact that it became more frequent at the end of the 20th century and into the 21st century has intrigued many scientists. We would like to know why this happened,” Stevens said. For decades, this has been a mystery. Now, it is just under one. If you look up at the sky at dusk or dawn and see a sea of ​​bright sky, you know that a rocket could have formed the clouds.