Not only will the rockets be built differently, but they also won't need to carry food or water, reducing weight and cost, as mentioned previously. NASA has estimated that sending a manned mission to Mars would cost at least billions of dollars (Mann - Humans VS Robots, 11). Rather than sending one manned mission, several robotic missions could be sent on site, allowing for even faster data collection. For some time, space funding has been a constant; between approximately 2012 and 2017, NASA was expected to receive approximately $17.7 billion per year, making robotic space exploration a much more fiscal solution (Mann - Almost Being There, 13). Cost has been one of the biggest, if not the biggest, issues with space travel, as the TAM 2011 space panel in Las Vegas explained.