Notices by Dr Megan Argo (astromeg@astrodon.social)

So #Boeing finally successfully launched their crewed launcher yesterday, and now #SpaceX have launched the next test flight of #Starship.

It's an exciting time for the future of space flight and space exploration, and the reusability of the SpaceX system will be revolutionary - once they complete the development phase, which they are making great progress towards.

I can't help but worry about the amount of stuff we are dumping in the atmosphere though. Every launch involves a huge amount of fuel, and every reentry involves burning material (even if whatever is reentering does not burn up on reentry).

The more we launch into space, the more we dump in the atmosphere. The faster the replacement cycle for our megaconstellations of satellites (powering our communications, internet, etc), the more of them we burn up when they get replaced.

The atmosphere is not unlimited. It took us a long time to realise that was true for the oceans. We must remember that this goes for the air we breathe, too.

In case you are wondering, there is research on the atmospheric impact of the space sector. See for example: Ryan et al (2023) "Impact of Rocket Launch and Space Debris Air Pollutant Emissions on Stratospheric Ozone and Global Climate"

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021EF002612

Good grief. Starlink v2 satellites are generating 32 times more radio emission than previous generations! This is totally blinding to radio telescopes and will stop us doing science in this part of the spectrum.

BBC News coverage: https://www.bbc.co.uk/news/articles/cy4dnr8zemgo

Journal article: https://www.aanda.org/articles/aa/full_html/2024/09/aa51856-24/aa51856-24.html

#astronomy #starlink #losingthesky