The U.S. is inching closer to a manned mission to Mars, but the clock is ticking on a bill that would formally ensure it is a policy priority for NASA.

In the 2015 film "The Martian," moviegoers got the most lifelike look yet at what a Mars mission could be like.

"I thought The Martian was an extremely interesting, well-done movie," said Dr. Byron Tapley, director of the Center for Space Research at the University of Texas Cockrell School of Engineering. A researcher specializing in orbital mechanics, Tapley is the principal investigator responsible for the Gravity Research and Climate Experiment (GRACE).

"In terms of the surface transportation mode, the movements, I think they did a pretty good job of capturing some of the difficulties that one would have to contend with there," said Tapley. "The getting there, I think, is fairly consistent with the way that we would think about doing it."

"The problem that I had with the actual transfer mode was on the way back home, when they discovered that he was alive, that procedure, essentially turning back around, picking up the capability, and making that swing back, that was a little bit of an extension of the fundamental principles that one would work with there," Tapley added.

Reality is now a small step closer. Last week, a U.S. Senate committee advanced a $19.5 billion NASA reauthorization bill carried by Texas Sen. Ted Cruz. It orders NASA to continue developing spaceflight technologies with the goal of a manned mission to Mars by the 2030s.

"It's doable," Tapley told KVUE. "With the commitment and the budgetary environment, one could do it, I believe, sooner than that, but you would do it with a little bit of a risk."

"You hear fairly widely divergent opinions on how well we have the medical conditions that the astronauts will have to undergo in hand, and what level of shielding we would need to put up there for radiation environments that they may encounter from a solar flare during the flight mode," Tapley explained, "But the ability to actually fly, do all of the engineering-related issues, I think we have developed a pretty good capability on that from the robotic exploration that we gone, the landers on Mars, and those things going forward."

A new age of spaceflight would also mean a renaissance for the Johnson Space Center in Houston, which has been home to Mission Control and the Astronaut program since the Gemini missions.

"Right now, there's a young boy or young girl sitting in a classroom in Houston, Texas," Cruz told the committee last week advanced, "And this bill ensures that he or she will have a chance, as will children all across this country, to become the first American to step foot on the surface of Mars."

The bill itself still faces some sticking points. It advises finding an alternative to a proposed asteroid retrieval mission backed by the White House, and discussions in the House have favored robotic exploration over manned missions. There are also those who continue to question why taxpayers should invest in space exploration.

"First of all, the fundamental question is the search for life on another planet, with the idea that we might go there," suggested Tapley. "But the big driver, I think, on essentially trying to get off the surface of the Earth and go forward is that we know effectively life is limited on Earth."

The bill must first be approved by the full Senate before heading to the House, where the clock will begin anew. It must be passed before the end of the year in order to head to the president's desk.