Unexpected noctilucent clouds outbreak over Europe continues

The unexpected display of noctilucent clouds all over Europe since June 23, 2024, has given rise to a couple of speculations as to why are these clouds forming during a solar maximum when high solar activity inhibits their formation.

Earlier this week on June 23, 2024, Europe experienced an unexpected outbreak of noctilucent clouds. Considering that the Sun entered the solar maximum this year the phenomena has baffled many since high solar activity typically inhibits the formation of NLCs.

The displays haven’t stopped and sightings have been reported from all over Europe even now almost a week after the initial displays began to show up:

So far, two theories in speculation could explain this out-of-place behavior of NLCs:

The first is the undersea eruption of the Tong volcano back in 2022 which released huge amounts of water into the atmosphere. Although the eruption took place 2 years ago, since water vapors take 2 years to circulate in the mesosphere; where the NLCs form we might be witnessing the effects of the eruption now.

The second theory is a large number of rockets that have been launched this year. Rocket fuels create water during combustion, which is released into the upper atmosphere, since, water is a key component in the formation of NLCs, the water-rich exhaust of rockets might be providing the fuel for the creation of these electric blue clouds. 124 rockets have been launched between January 1 and June 27, 2024, most of which were launched by Space X.

Seven rockets were launched in the past two weeks alone, the most notable of which was the launch of The Falcon Heavy rocket on June 25.

As of right now, there is no certainty regarding whether or not these events are linked, and why we are seeing these unexpected noctilucent clouds mainly due to a lack of satellite data tracking the detailed circulation of water vapor in the upper reaches of the atmosphere.

References:

¹ What’s up in space – SpaceWeather – June 29, 2024

Featured image: Noctiluques Parisiens. Taken from Paris on June 28, 2024. Credit: Bertrand Kulik. Used with permission.