Peter Capaldi's not just a fan of science fiction. This guy loves real deal science, too.。

Dr. Who。's beloved twelfth doctor made an appearance at the London March for Science on Saturday, much to the delight of science, and Time Lord fans alike. 。

SEE ALSO:The new 'Doctor Who' trailer promises an outrageously epic series 。

Devotees were especially glad to see Capaldi because he'll be leaving the show at the end of the year -- but, hey, making your mark at the March for Science definitely counts as "out with a bang," right?

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He even partnered up with the World Wildlife Federation. 
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Now, if we could only find out where he parked the TARDIS. 。

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