Star Wars: The Force Awakens doesn’t open for another week, but it’s safe to say that the seventh installment of the franchise might costar the cutest droid in that galaxy far, far away. And while BB-8 is charming, according to Brett Kennedy, a roboticist at NASA’s Jet Propulsion Laboratory, the bot isn’t exactly practical.

“Trying to roll up and over anything is extremely difficult,” Kennedy says in the WIRED video above.

Kennedy talks through the major mechanical players in the Star Wars-verse, and says that NASA would take C-3PO to space, but not R2-D2 (though he does describe R2 as a droid that’s close to his heart). Even better? It’s one we could potentially make IRL.

“We can build an R2 today. A lot of what it does is perfectly possible with what we have,” Kennedy says. 

Kennedy also compares NASA’s Robonaut and Valkyrie droids to C-3PO. While they’re impressively similar to the fictional, gold-plated droid, C-3PO has the advantage of spine flexibility, something real-life scientists still struggle to emulate.  

Banner image screenshot via YouTube.

[h/t EW.com]