This recent launch of the NASA Space Shuttle Discovery is a bittersweet moment that highlights the success of America’s manned space program, but at the same time moves our nation one step closer to the plans of the Obama Administration to voluntarily surrender our country’s half-century of leadership in space exploration.

It is ironic that this mission will considerably expand the scientific capability of the International Space Station (ISS) and bring it closer to final assembly while we move toward embracing complete dependence on Russia for future access to the space station. Six months from now if the remaining flights are completed as scheduled, U.S. crew members along with European, Japanese and Canadian crew members, for whom the U.S. is also obligated to provide transportation to the ISS, will only be able to fly there aboard Russian Soyuz spacecraft at a cost to American taxpayers of $51 million per seat. That’s a combined total of at least $300 million per year, assuming the Russians don’t raise the price once they are the only available provider of launch services.

This will be the case until an asyet unknown commercial provider can design, build and test an asyet unidentified vehicle on an asyet undefined schedule, which most experts expect to be from five to seven years away. Just as disturbing, according to a recent report of the General Accountability Office, is the absence of the space shuttle will mean the space station will be vulnerable to the potential failure of major components or systems whose replacement or return to earth for repair and redelivery were provided by the space shuttle, threatening years of research and billions in investment.

In fact, the ability of the space station to be used for the science and research it was designed and built to conduct could be compromised by the inability to ensure the delivery of research materials and equipment to the station, and especially to return samples home for analysis of the in-orbit research.

This also will have a direct impact on Texas. The Johnson Space Center (JSC) in Houston is the premiere NASA center for the International Space Station (ISS) and human space flight, scientific and medical research efforts. The JSC employs over 3,400 civil servants and more than 13,000 contract employees. In total, the JSC supports the Houston area by generating an economic impact of over $4 billion and 35,000 jobs. The potential loss of this workforce’s skills during the transition has long-term implications for our state and its continued support of space flight programs.

I have legislation which would keep space shuttles flying until it can be clearly determined that the space station is fully equipped to do research and has sufficient spares and replacement parts to keep functioning in the absence of the shuttle’s capability. It would also accelerate the development of a shuttle-derived replacement, which could be available in time to narrow or close the gap after the shuttle is retired, whenever that is determined to be. My plan would be budget neutral.

Our nation must not be forced to choose between maintaining our independence in reaching space and investment in the next generation of space vehicle. We can and must do both. By maintaining our independence from other nations in reaching space, the U.S. can fully realize the research potential of the space station as a national lab and protect our nation’s security and economic interests.

Discovery’s important two week mission, which began on April 5th, will bring needed supplies and repairs to the International Space Station in order to keep the facilities operational long after NASA retires the space shuttle. This could be an empty and hollow mission unless Congress and the Obama Administration act to ensure America’s continued access to space.

Until we fully understand the impact of the shuttle’s absence to the viability of the space station, and until we have a clear path toward replacing the shuttle’s crew and cargo delivery capabilities, it is irresponsible to continue down the path toward the virtual extinction of U.S. human spaceflight capability.

Kay Bailey Hutchison is the senior U.S. Senator from Texas and is the Ranking Member of the Senate Committee on Commerce, Science, and Transportation.