The U.S. House of Representatives and Senate have begun hammering out a compromise spending measure they hope to enact by Nov. 18 to fund NASA and several other federal agencies for 2012 and keep the rest of the government running into December.

House and Senate appropriators convened a conference committee Nov. 3 to iron out their differences on a package of three previously separate spending bills, including those funding NASA, weather satellite programs at the National Oceanic and Atmospheric Administration, and the Federal Aviation Administration’s Office of Commercial Space Transportation.

The Senate set the stage for the legislative conference Nov. 1 by approving H.R. 2112, a House-adopted agriculture spending bill the Senate amended to include its versions of the three previously separate bills.

NASA funding is among the differences House and Senate conferees must resolve before the two chambers can give final approval to the so-called minibus the week of Nov. 14.

House appropriators voted this summer to fund NASA at $16.8 billion — about $1.6 billion below this year’s level — and recommended canceling the overbudget James Webb Space Telescope. The Senate bill, in contrast, would fund NASA at $17.9 billion and include additional money for Webb.

Appropriators plan to attach additional spending bills to the minibus, including a temporary spending resolution that would keep the government running into December. The current continuing resolution expires Nov. 18.