Though they don’t get the same hype as space missions that face outward, ESAs earth observing satellites are super exciting. The data is open, and people come up with things to do with it the mission designers never imagened. Sentinel-2, for instance, was supposed to track things like icebergs, but people have also used the data to detect buildings with unstable foundations by measuring small changes in the orientation of their roofs. I’m curious to see all the un-thought-of uses Aeolus will be used for!

I had never heard of a sun-synchronous orbit before. Intuitively it shouldn't work; if you're orbiting the earth in a plane perpendicular to the sun now, then in three months' time you'd expect to have moved round and the sun to be in that plane.

However, it turns out that the orbital plane can be made to precess by means of interaction with the earth's equatorial bulge: https://en.wikipedia.org/wiki/Sun-synchronous_orbit#Orbital_...

Not mentioned in the article. Will be orbiting at 320 km from the surface of the earth, for comparison ISS is between 403 and 406 km.

Edit, Orbital times:

Aeolus 60 minutes

ISS 92.49 minutes

… which means its lifetime is rather limited. It can carry only so much propellant for orbital station-keeping.

Designed to last 3 years. Previous low orbiting missions like GOCE demonstrated that the drag was less than expected so I would not be surprised if it went beyond 3 years.

I’m guessing though that the data will lead to better models and hence better predictive ability even after it’s deorbited?

This looks a lot more sophisticated than currently operating satellite wind mapping, which uses radar deflection off water to estimate wind speed and direction. I hope they make data as easily available as noaa:

https://manati.star.nesdis.noaa.gov/datasets/ASCATData.php