They just ended with youngblud doing Bowie and then randomly showed a tweet from Rick Astley.
Why Rick Astley?
Brian May, he’s got a PhD in astrophysics...
What’s Astley got that gets him on the closing credits of one of the greatest space exploration moments of all time?
I think it might have been a case of the NASA website crew having a bit of a laugh by sneaking in a variation of the phenomenon known as "Rickrolling".
A true "Rickroll" would have seen them play the video to "Never Gonna Give You Up" instead of Yungblud's cover of "Life on Mars", but they probably realised it would be taking the joke a little too far, so the Astley tweet was probably the next best thing that they thought they could get away with.
I can't think of any other reason why they would have used the solitary tweet by Rick Astley over anybody else other than it being NASA's nod to Rickrolling.
"Rickrolling" started around 2008 and involves the unexpected appearance of the video to "Never Gonna Give You Up" at various events and on the internet.....
https://en.m.wikipedia.org/wiki/Rickrolling
Edit: It appears that there are others who share my theory...
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