Emre Kelly

FLORIDA TODAY

A Kennedy Space Center-led effort to bolster our understanding of growing plants in space will hitch a ride on an Atlas V rocket to the International Space Station on Tuesday.

Astronauts on deep-space missions could one day munch on fresh produce thanks in part to NASA's Advanced Plant Habitat, a mini fridge-sized experiment that will join 7,600 pounds of science, cargo and supplies bound for the orbiting outpost. The 194-foot rocket is scheduled to launch from Cape Canaveral Air Force Station's Launch Complex 41 with an Orbital ATK Cygnus spacecraft at 11:11 a.m., the opening of a 30-minute window.

APH is scheduled to depart exactly three years after its predecessor, the Vegetable Production System, launched to the space station aboard a SpaceX Falcon 9 rocket. Dubbed "Veggie," that experiment – also spearheaded by KSC scientists and still active – in 2015 produced lettuce that became the first NASA-grown food to be consumed by astronauts.

[Weather favorable for Tuesday Atlas V launch from Cape Canaveral]

APH might be launching years later, but it isn't without advantages. Whereas Veggie's plants were covered and relied on unaltered air from inside the station, the new system has the ability to control the environment within a plant chamber. To stimulate growth, it features a brighter array of light-emitting diodes, or LEDs, but now includes white and infrared light, bringing its total output to four times that of Veggie.

But the biggest difference, according to program manager Bryan Onate, is the inclusion of 180 sensors and the reduction in crew time they will bring.

"It's really a way for the scientists to modify the environment – the light, the water, the atmosphere," Onate said during a conference call with reporters in March. "We'll learn a lot of invaluable information as we move on beyond low Earth orbit and move out to Mars and do food production out there in the future."

Aided by cameras, the system's sensors will relay real-time information to scientists on the ground at KSC, who will control everything but maintenance, such as plant thinning and, ultimately, harvesting. The plants are grown in a science carrier, which sits at the bottom of the habitat and is about the size of a large pizza box, Onate said.

Two seed varieties – arabidopsis, a small plant related to cabbage, and dwarf wheat – will be grown after installation as a checkout of APH's systems and performance. If successful, arabidopsis will be the main crop for the first experiment named Plant Habitat 1.

Dr. Howard Levine, chief project scientist for the habitat, said its size and enhanced light production for photosynthesis will allow astronauts to one day grow larger, more nutritionally dense plants.

"It will be able to accommodate larger plants than have often been used," Levine said. "This will allow you to grow many of the non-traditional, but valuable food crop plants that previously we weren't able to accommodate."

While most of the habitat's hardware will launch on Tuesday's Atlas V mission, some additional components will fly aboard SpaceX's next Falcon 9 launch to the ISS, Levine said. The system was developed by NASA and ORBITEC of Madison, Wisconsin.

Other experiments packed into the spacecraft include an investigation named "ADCs in Microgravity" that could improve cancer-fighting chemotherapy drugs; magnetized tools that will help reproduce Earth-like cell cultures on the space station; and Saffire III, an experiment that will begin after Cygnus departs the ISS in July.

The Saffire investigation, which aims to better understand how to detect and clean up after fires in space, will light a fire on a panel for about 20 minutes before the spacecraft burns up in Earth's atmosphere.

Cygnus will also deploy 38 CubeSats, which are miniaturized satellites designed for research purposes, primarily built by university students from around the world.

The launch of Atlas V was delayed from March after two separate issues with hydraulics. While working to fix the first hydraulic issue on ground support equipment, ULA found a second issue with a booster hydraulic line. Officials said earlier this month that both issues had been resolved.

SpaceX, meanwhile, is expected to launch a Falcon 9 rocket from KSC's pad 39A no earlier than April 30. That mission will launch a satellite for the National Reconnaissance Office, designated NROL-76. The rocket's first stage will attempt to land at Cape Canaveral Air Force Station's Landing Zone 1.

Contact Emre Kelly at aekelly@floridatoday.com or 321-242-3715. Follow him on Facebook and Twitter at @EmreKelly.

Launch Tuesday

Rocket: United Launch Alliance Atlas V

Mission: Orbital ATK Cygnus spacecraft for ISS resupply

Launch Time: 11:11 a.m.

Launch Window: 11:41 a.m.

Launch Complex: 41 at Cape Canaveral Air Force Station

Weather: 90 percent "go"

Join floridatoday.com starting at 10 a.m. for countdown chat and updates, including streaming of NASA's webcast.