New Delhi, Feb. 18 -- NASA astronauts Sunita Williams and Butch Wilmore, who have been stuck in space for nearly eight months, are likely to face a tough task re-adjusting to the atmosphere on Earth. "Gravity is really tough, and that's what we feel when we get back," said astronaut Butch Wilmore, who will return to Earth with Sunita Williams, likely on March 19.

In an exclusive interview with CNN, Wilmore said that the two astronauts will even "feel the weight of a pencil" when they reach back on Earth.

The astronauts said, "When you get back [to Earth], Gravity starts pulling everything to lower extremities; fluids will be pulled down...it's really gonna be different...you don't even feel a pencil when you lift it [on Earth], but we w...