The U.S. Space Force is assessing whether to recommend the creation of a Space National Guard or the formation of a combined active duty and Reserve component that has members of the Air National Guard.

Since 2020, Space Force has said that 1,500 of its members are members of the Army and Air National Guard. Last September, Space Force said that it has 13,000 members–a figure which would mean that nearly 12 percent of the Space Force are from the Guard, which has 17 units dedicated to space missions in Guam and seven states–Florida, Colorado, New York, California, Ohio, Alaska and Hawaii.

Such Air National Guard units include Alaska’s 213th Space Warning Squadron, California’s 216th Space Control Squadron, Colorado’s 137th Space Warning Squadron, and Florida’s 114th Space Control Squadron. The National Guard Bureau has said that the Air National Guard provides the nation’s ballistic missile warning and 60 percent of the Space Force’s deployable offensive space electronic warfare.

At a hearing of the Senate Armed Services Committee’s strategic forces panel last week on the Space Force fiscal 2023 budget request, Sen. Mark Kelly (R-Ariz.) asked Gen. David Thompson, vice chief of space operations, about the assessment and appeared to throw cold water on the idea of creating a new Space Force component.

“That second option assumes that current Air National Guard members will transfer to the Space Force under a mixed full’time, part-time active component model,” Kelly said. “This ignores the fact that many folks who joined the Air National Guard did so because of geographic stability that it offers the members and their families, as well as the opportunity sometimes to serve their state.”

Thompson, however, said that the Space Force assessment, which is to be finished this year in time for the fiscal 2024 budget, does not assume that Guard members will join a new Space Force component. Rather, the Space Force is determining “what would be required to replace those members by Space Force members, the numbers it would take, the training time and resources it would take, and the corresponding degradation in mission as we bring those units back up to full status.”

“There are some that think that a large number of Guard members may transition,” Thompson said. “There are others that don’t believe that’s the case. In our current assessment, we are not making the assumption that a large number of Guard members would.”

Thompson testified that Space Force will have to avail itself of one of the two options, as “we cannot do without the capability and missions they [Guard members] provide today moving into the future.”

Last week, Sen. Dianne Feinstein (D-Calif.) and Sen. Marco Rubio (R-Fla.) introduced the Space National Guard Establishment Act to create a Space National Guard. Rep. Jason Crow (D-Colo.) introduced a companion bill in the House last year.

“Without a National Guard component for Space Force, we risk losing many talented individuals who want to keep serving their country and their states after they leave active duty, and that is simply unacceptable,” Feinstein said in a statement last week. “Creating a Space Force National Guard would also save money and ensure a smoother process in the event we need to activate personnel. Not establishing a Space National Guard was a mistake when Space Force was created, and this bill will remedy that.”

Last December, Feinstein and other lawmakers signed a a bipartisan, bicameral letter to the Senate and House Armed Services Committees supporting the inclusion of a Space Force National Guard in the fiscal 2022 National Defense Authorization Act, but the provision was not in the final bill.