The proposed budget includes $1.2 billion for NASA's planetary science division, down from the $1.4 billion in its 2013 budget.
The division is especially important to JPL because it includes locally developed missions such as the Curiosity rover project and a planned mission to Jupiter's moon, Europa.
At a news conference Wednesday, NASA administrator Charles Bolden said that the $17.7 billion apportioned to the agency as a whole in the president's latest budget proposal would ensure the United States remained the world leader in space exploration. But it would not be without challenges.