All philatelic mail returned from the station gets the "Barnacle Goose" cachet that was applied to this envelope. It was also signed by researchers Nico van den Brink and Martine van den Heuvel-Greve and base leader Maarten Loonen. I wish I had sent a bigger envelope. Next time.
The station website has lots of information about this tiny research base and the team that supports it. Dr. Loonen keeps the site updated with photos and videos about their research and Ny-Ålesund. A very informative site. And while looking through his blog I came across an entry that mentions preparing philatelic mail at the Ny-Ålesund post office. You can even see my cover in the image on the left side of the counter.