In the category "Science" we currently track items of 35 persons. The most popular ones, by number of traded items, are:

Buzz AldrinNeil ArmstrongFelix Baumgartner
Helen SharmanCharlie DukePatrick Moore
Gene CernanValentina TereshkovaJim Lovell
Edgar MitchellYuri GagarinMike Bannister
Dave ScottJim IrwinAlan Bean
John GlennMichael CollinsScott Carpenter
Al WordenFred Haise 

You can find all people that we're currently tracking items for in the alphabetical index:
A    B    C    D    G    H    I    K    L    M    S    T    W    Y