The Air Force is zeroing in on military bases to potentially house President Trump’s proposed U.S. Space Command, with the short list of contenders located in Colorado, Alabama and California, according to CNN.

An Air Force memorandum obtained by the network identified six potential bases, four in Colorado and the other two in California and Alabama, according to CNN. While the memo indicated the findings were approved by Air Force Secretary Heather Wilson, an Air Force spokesperson told the network that Air Force personnel have not yet sent a list of base candidates to Wilson.

{mosads}The memo puts the “projected manpower” for the base at 1,450 personnel, including 50 contractors, 827 civilians, 183 enlisted personnel and 390 officers, according to CNN. About 350 of the personnel would come from the existing Joint Force Space Component Command, currently part of U.S. Strategic Command.

The reported finalists are Colorado’s Buckley Air Force Base, Cheyenne Mountain Air Force Station, Peterson Air Force Base and Schriever Air Force Base, the Army’s Redstone Arsenal in Alabama and Vandenberg Air Force Base in California.

“Placing United States Space Command on a Department of Defense space installation will align the command with critical space force expertise and provide resident military, civilian, and commercial space manpower for United States Space Command recruiting and retention,” a document attached to the memo said, according to CNN.

The Senate Armed Services committee is set to hold its first hearing on Trump’s Space Force proposal this week.

“A coherent space strategy is an integral part of our National Defense Strategy,” committee Chairman James Inhofe (R-Okla.) said in a statement. “I look forward to hearing from Pentagon leadership about what they see as the necessary capabilities of a space force, the costs and benefits associated with their solutions, and what our full range of options are.”