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Delphini-1 is taking the deep dive soon

Have a guess at the Delphini-1 decay date and win a LEGO model

26.01.2021 | Ole J. Knudsen

Delphini-1 alone in space. Photo: NASA

Delphini-1 alone in space. Photo: NASA

Our small student satellite has been our trustful companion in orbit for some two years now, but all things must pass. From the beginning we knew that the thin atmosphere even at the altitude of 400 km is able to slowly brake a satellite, eventually sending it down to a fiery end in the lower atmosphere.

Depending on the density of the atmospheric molecules this happens sooner or later, and the Solar activity is the main player. During the last couple of years the Sun has been very quiet, and this has given us much longer time than anticipated to play with our small 10 x 10 x 10 cm friend in orbit.

As you can see from the curve here, the altitude is now diminishing at a growing rate, but slightly slower than what the theoretical green curve predicts. We expect Delphini-1 to end its lifetime sometimes around 800 days after launch (which was on 31. january 2019).

On what date the decay will happen is anyones guess, so why not your's?

E-mail your guess to our Delphini manager Mads Fredslund Andersen madsfa@phys.au.dk asap no later than 7 February 2021. The one closest to the actual date will recieve a 1:1 scale model of Delphini-1 in LEGO bricks.