WASHINGTON — NASA’s Goddard Space Flight Center in Greenbelt, Md., is laying the groundwork to develop an unpressurized cargo (UPC) capability for the Constellation program’s Orion Crew Exploration Vehicle, an effort meant to offer free rides to low Earth orbit for science and technology payloads as soon as 2015.
The administration of U.S. President Barack Obama is weighing options that include canceling parts of Constellation, a 5-year-old effort to build new spacecraft and rockets optimized for sending astronauts to the Moon. In October, a White House-appointed panel determined Constellation is incompatible with NASA’s current budget. In an Oct. 22 report to senior NASA and White House officials, the panel, led by former Lockheed Martin chief Norm Augustine, outlined a number of alternatives to Constellation, some of which would abandon Ares 1 and Orion in favor of buying comparable launch services from the private sector.
Despite the uncertainty surrounding the program’s future, NASA gave Goddard’s Exploration Systems Projects Office the green light this summer to begin planning the development of a UPC capability for Orion missions to the international space station. NASA approved the project after Orion passed its preliminary design review in July.
“This is now a baselined concept to allocate at least 600 kilograms of unpressurized cargo for every launch of Orion to the space station,” said Neal Barthelme, UPC deputy project manager, adding that the UPC effort could allow scientists and technologists to test prototype components and instruments in space to help determine flight readiness for missions.
The UPC capability is baselined for Orion’s service module, which is mounted directly below the crew module. Barthelme said the service module, sized for trips to the Moon, is large enough to accommodate propellant and other life-support requirements, as well as a cargo carrier capable of ferrying 600-kilogram payloads into low Earth orbit. Japan’s unmanned H-2 Transfer Vehicle, which made its debut this year, is designed to haul 10 times as much cargo to the space station, around 1,500 kilograms of it unpressurized.
Michael Weiss, UPC project manager, characterized the Orion payload capacity requirement as a floor, rather than a ceiling.
“It starts with 600 [kilograms], and depending on the mission configuration, there could be more capability. But it starts at 600 kilograms and 160 cubic feet [4.5 cubic meters], which is equivalent to a Small Explorer-class payload,” Weiss said, referring to a class of NASA science satellites generally weighing 180 kilograms to 250 kilograms. “And we’re using the same concepts that we’ve used before to essentially be the one-stop shop for these science and technology payloads.”
Finding no-cost flight opportunities for payloads is nothing new for Goddard. The flight center manages the Shuttle Small Payloads Project, offering free flight opportunities aboard the space shuttle through the Hitchhiker, Get Away Special and Space Experiment Module projects.
“We will be the group to carry on the work we did with the shuttle where we found lots of ways to fully utilize it for access to space for scientists and technologists across the country,” Barthelme said.
Although the effort is still in the planning stages, Barthelme said Goddard would build the Orion carrier module, work with users to ensure compatibility, and integrate the experiments. Three different flight configurations are on the drawing board for the carrier: a free-flyer capability to low Earth orbit, an extractable payload to the space station, and a capability that would fly experiments on a pallet affixed to the UPC carrier for the duration of the mission. However, it would be jettisoned before Orion re-enters Earth’s atmosphere, and thus serve only as a means for users to gather data.
Barthelme said the Orion carrier system will offer scientists and technologists built-in safety at reduced cost.
“That’s the beauty of this concept: We’ve designed the carrier system to put the safety inhibits in place,” Barthelme said. “So when they interface to our carrier, we work with the service module in Orion to put the safety in place where the principle investigators and the scientists don’t even have to think about it.”
Goddard expects to begin offering payload accommodations in 2015, a target that coincides with the Constellation program’s stated goal for fielding Ares 1 and Orion. The agency is in search of a so-called trailblazer mission to demonstrate one of the UPC’s three operational modes on Orion’s maiden flight.
“There’s an incredible backlog of science and technology payloads awaiting their ride into space,” Weiss said. “We hope to provide that service.”
