Earlier this year, President Trump inspired hope in many Americans that have long wished to see a resurgence in NASA’s manned space exploration endeavors, when he announced his goal to send human beings to Mars.

The president was so passionate about a manned trip to mars, that during a teleconference with NASA astronaut Peggy Whitson aboard the ISS, he asked Whitson what kind of timeframe we can expect before placing American feet on the Red Planet.  Whitson told him the budget he proposed could get them there as soon as the 2030s, which President Trump didn’t seem pleased with.

“Well, we want to try and do it during my first term or, at worst, during my second term, so we’ll have to speed that up a little bit, okay?” The president told her.

“We’ll do our best,” was all America’s most experienced space walker could muster in response.  Now, it would seem even their best can’t cut it with NASA’s sparse budget.

During a meeting of the American Institute for Aeronautics and Astronautics on Wednesday, William Gerstenmaier, NASA’S chief of Human Space Flight, admitted that the funds just aren’t there to mount a successful Mars mission.

“Through this horizon, through the 2030s, I can’t put a date on humans on Mars, and the reason really is … at the budget levels we described, this roughly 2 percent increase, we don’t have the surface systems available for Mars,” Gerstenmaier said. “And that entry, descent and landing is a huge challenge for us for Mars.”

While the nation’s civilian space agency has not provided an exact figure as to how much such a trip would truly cost, some experts within NASA have speculated.  In 2012, Brent Sherwood, who runs the famed Jet Propulsion Laboratory for NASA, estimated that such an endeavor would likely cost somewhere in the neighborhood of $100 billion over the course of thirty to forty years.  Pascal Lee, the director of the Mars Institute, provided a more expensive estimate this May; suggesting the trip could cost tax payers as much as $1 trillion over 25 years.

The Apollo Program that took America to the Moon in the 1960s and 70s cost an estimated $210 billion or so, when adjusted for inflation.