There was a time when you could find spacecraft clean rooms in two sizes - big and bigger. After all, these harsh-white, sterile environments have to handle very large spacecraft, support equipment, and a small legion of highly trained technicians and engineers.

Here at NASA's Jet Propulsion Laboratory in Pasadena, California, we have two monster clean rooms of our own - called High Bays 1 and 2. In these hallowed, dustless halls, the likes of the Voyager, Galileo and Cassini spacecraft and the Curiosity Mars rover were assembled, disassembled, re-assembled, tested and packed for shipment to NASA launch pads and finally, for launch into space.

There was a time when you could find spacecraft clean rooms in two sizes - big and bigger. After all, these harsh-white, sterile environments have to handle very large spacecraft, support equipment, and a small legion of highly trained technicians and engineers.

Here at NASA's Jet Propulsion Laboratory in Pasadena, California, we have two monster clean rooms of our own - called High Bays 1 and 2. In these hallowed, dustless halls, the likes of the Voyager, Galileo and Cassini spacecraft and the Curiosity Mars rover were assembled, disassembled, re-assembled, tested and packed for shipment to NASA launch pads and finally, for launch into space.

But today, more than ever, spacecraft come in all shapes and sizes. The bigger ones already have their clean room needs covered, but what about the little guys? Well, JPL has them covered too, with the new Integrated CubeSat Development Laboratory.

CubeSats are small, modular spacecraft, anywhere from the size of an overgrown Rubik's Cube to that of your purse or attache case. So small are they in stature, the CubeSats almost always hitch a ride into orbit aboard a rocket that is launching another, much larger payload, and has some extra room.

The team of scientists and engineers working on them also is small. The small size helps make the spacecraft relatively inexpensive, and tiny CubeSats are becoming the next big thing in space exploration.

Since the earliest days of space exploration, NASA has known that dirty environments do not mix with wiring, exposed circuit boards and sensitive instruments destined for space.

But traditionally, CubeSats have been assembled and tested in either your garden-variety workshop environment that, on a good day, gets dusted and swept, or on a "clean bench," where a metal hood overhanging a workbench circulates air through a HEPA filter, then directs the now-scrubbed air over the bench's work surface. Until this summer, JPL CubeSats were being assembled wherever an empty clean bench at the lab could be found.

"CubeSat projects ended up being scattered around the lab," said Charles Norton, Engineering and Science Directorate Lead for SmallSats at JPL.

"It was difficult to get the teams together to collaborate on planning, technical issues, and institutional processes and procedures. On top of that, we were being chosen for more CubeSat projects, so in the summer of 2013 we formed a team to establish a suitable permanent location for a CubeSat clean room."

What Norton and company found was the E-Nose Lab. Consisting of 1,250 square feet of prime JPL lab space, it was formerly dedicated to the design and perfection of a hyper-sensitive smell sensor for the International Space Station.

The E-Nose flew aboard the space station, and after that, the lab awaited a new task. So out went the vestiges of the E-Nose, in came the isolated electrical circuits, electrostatic discharge (ESD) flooring, cryogen ventilation systems and other tools of the trade for people who need to keep their rooms hyper-clean.

JPL's Integrated CubeSat Development Laboratory (the cleanroom's official name) was dedicated in June 2014, and CubeSat teams began tasting the freshly scrubbed air soon after.

There are currently three projects in various stages of development in JPL's CubeSat cleanroom. MarCO (Mars Cube One) is headed to the Red Planet. ASTERIA (Arcsecond Space Telescope Enabling Research in Astrophysics) and TEMPEST-D (Temporal Experiment for Storms and Tropical Systems - Demonstrator), are two separate missions, each slated to go into Earth orbit. When MarCO leaves the lab, it is slated to launch in March. The RainCube CubeSat will take its place.

By the spring of 2016, the CubeSat clean room will be home to four separate CubeSat missions - which happens to be the facility's maximum occupancy.

"Never before has there been such mission diversity in one location," said John Baker, program manager for planetary SmallSats at JPL.

"We have CubeSats in development that will not only travel to Earth orbit, but to the moon and asteroids, comets and Mars. Having a cleanroom dedicated to just CubeSats is great because it not only centralizes their development and allows them to share resources, but we're finding that it fosters cooperation and support between the individual mission teams.

The MarCO mission, the first progeny of JPL's CubeSat cleanroom to fly, will do so next March when it hitches a ride on NASA's InSight mission to provide a live data relay as Insight lands on Mars.