Sean Rossman

USA TODAY

NASA expects to have a better idea by next month whether it will put astronauts aboard a new rocket planned to launch in 2018.

The agency started a feasibility study as to whether it is possible to put humans on the test flight Exploration Mission-1 when it launches from Kennedy Space Center in Florida. On Friday, the agency's associate administrator of human explorations William Gerstenmaier said he expects preliminary results in about a month.

The EM-1 is an ambitious three-week mission that NASA boasts will "launch on the most powerful rocket in the world and fly farther than any spacecraft built for humans has ever flown." The spacecraft is expected to orbit the moon, collect data, and return to Earth while laying the groundwork for a trip to Mars.

As it stands now, the EM-1 flight is unmanned. Adding astronauts to the mission, if that's what is decided, would add time and money to the process. However, adding astronauts to the EM-1 would advance a manned space flight by years. The plan currently is for astronauts to board a second flight, EM-2, which has a tentative launch date of August 2021.

After conversations with President Trump's transition team, acting NASA administrator Robert Lightfoot last week announced the feasibility study to examine the risks and rewards of moving up a manned launch.

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Gerstenmaeir denied the agency was being pushed to man the Orion sooner rather than later because of Trump's administration, which has shown support for advancing a space mission. He said the agency wasn't provided funding or time guidelines.

"There's not pressure to go do this," Gerstenmaier said. "This is something we're going to evaluate ... We'll see what the results look like coming out the other side."

The data, Gerstenmaier stressed, will lead NASA to its decision. The question for the agency, he said, relies on weighing the safety risks associated with the launch versus the benefits. The benefit of an early launch, he explained, is the ability "to test systems in a rigorous way with crew on board."

NASA's Aerospace Safety Advisory Panel has urged caution at the prospect of a manned EM-1. The advisory panel stressed NASA needs a "compelling" reason for risking the lives of astronauts.

Gerstenmaier said he's assembled a team to explore the additional funding and time needed to put a man on the EM-1. He also appeared open to pushing the mission back, asking the team to keep its timeframe to no later than 2019.

William Hill, NASA's deputy associate administrator for exploration systems development, said a crew on EM-1 expands the possibilities of what can be done on EM-2.

Hill or Gerstenmaier didn't give a hard timeframe as to when the study would be complete, but added it wouldn't slow down the current plan for EM-1. Gerstenmair said there wouldn't be a firm recommendation at the end of the study. The final decision, he said, will come after an agency wide discussion that includes astronauts.

"We'll go through all the activity to make sure we understand the risks associated with this flight," Gerstenmaier said. "We need to look at what do we really gain by putting crew on this flight."

Follow Sean Rossman on Twitter: @SeanRossman

James Dean at Florida Today contributed to this story.