WASHINGTON — NASA is considering merging its Exploration Systems  and  Space Operations mission directorates to better align with the U.S. space agency’s manned spaceflight goals, according to NASA officials.

In a Dec. 20 memo to agency employees, the heads of NASA’s Exploration Systems and Space Operations mission directorates said they had been tasked by NASA Administrator Charles Bolden to produce a plan by early 2011 for combining the two organizations.

“With the upcoming retirement of the Space Shuttle and the likely transition away from the Constellation Program, planning is underway that could lead to NASA’s Space Operations and Exploration Systems Mission Directorates merging to create a new directorate to manage the integrated human spaceflight portfolio for the Agency,” wrote Bill Gerstenmaier and Doug Cooke, associate administrators for NASA’s Exploration Systems Mission Directorate and Space Operations Mission Directorate, respectively.

“While there has not been a final decision made, we wanted to fully inform you of this planning and the fact that we will be working the upcoming OMB ‘passback’ as an integrated team,” the memo reads, referring to the White House Office of Management and Budget’s process for setting spending ceilings for U.S. government agencies to use in drafting their annual budget requests.

The new organization, according to the memo, “would manage the International Space Station, Commercial Crew and Cargo, Space Launch System and Multi-Purpose Crew Vehicle Programs, among others.”

The document also says the merger would combine the directorates into a single organization, rather than making one directorate subordinate to another. An underlying goal of the effort is to make sure “everyone has a home in the new organization.”