Philadelphia will soon be mission control for the world's biggest mass collaboration.

"As of right now, this looks to be the largest global hackathon-type event," period, said Deborah Diaz, the deputy chief information officer at NASA. The space agency is presenting the International Space Apps Challenge on April 20 and 21.

The two-day civic hackathon will span 83 locations across the globe. Philadelphia will be the "Global MainStage," where winning local ideas will bubble up to be judged by a panel of international experts.

NASA says more than 5,000 people — ranging from web developers to citizen scientists — are registered to attend, with another 1,000-plus expected to participate virtually.

"This is something over an 83-hour period, over a weekend, where you have volunteers around the world all doing this mass collaboration to really improve life on space and life on Earth," Diaz said.

Participants are tasked with tackling dozens of space-related challenges. They include improving a web app that helps you spot the international space station; designing a miniature module that could hitch a ride to Mars; and visualizing invisible solar phenomena.

Judges will highlight five winning solutions, in categories ranging from "Galactic Impact" to "People's Choice."

This year's hackathon is a scaled-up version of a similar event last year.

Philadelphia was chosen as Global MainStage to correspond with both the Philadelphia Science Festival and Philly Tech Week.

As for the goal of the Space Apps Challenge, Diaz says it's simple: "To actually improve how we do work here at NASA and other space agencies."

Update

Azavea, the GIS firm organizing the local event, is still accepting registrations for both the free hackathon itself and the opening reception on Friday night.

The weekend hackathon will take place at Drexel's ExCITe Center, located at 3401 Market St.