It’s the ninth week of spring quarter. Phoenix Biology and 10 other science clubs have gathered on the main quad for Sciencepalooza, a celebration of science and engineering.

Pau Oliveres, SB’19 (above, in white T-shirt) of chemistry club Benzene is making dairy-free coconut ice cream with a canister of liquid nitrogen, which has a temperature of 77 Kelvin, or negative 200 Celsius. “It will cause deep tissue damage if you stick your hand in it,” Naomi Yamamoto, SB’19, explains nonchalantly.

“It’s only dangerous if you dunk your hand in,” Oliveres reassures a student waiting for ice cream. “See, it just got on my hand. It’s fine.”

There’s also regular chocolate ice cream. As Alex Feistritzer, Class of 2020, (above, in black) is pouring it out, a paper airplane from the Engineering Club circles through the treetops and wedges itself in his hair. The propeller, driven by a tiny motor, buzzes softly. “I thought it was a cicada,” Feistritzer says.

At the Paleo Club table, Marianna Karagiannis, Class of 2021 (above), shows off a cast of a velociraptor skull. Casts are often more useful than the original specimens, she explains, because you can take a cast apart and study the morphology.

Asked about her T. rex jewelry, Karagiannis notes that T. rex skeletons had traditionally been put together incorrectly, with the ulna and the radius reversed. T. rex’s tiny arms didn’t stick up uselessly in the front; they stuck out (still a little uselessly) to the side.