WASHINGTON — A top senator says President Barack Obama and NASA are planning for a robotic spaceship to lasso a small asteroid and park it near the moon. Then astronauts would explore it in 2021.

(VIDEO: How to Land on An Asteroid)

Sen. Bill Nelson of Florida said the plan would speed up by four years the existing mission to land astronauts on an asteroid by bringing the space rock closer to Earth.

An artistic image depicts an astronaut performing a tethering maneuver at an asteroid.

(NASA)

Nelson, who is chairman of the Senate Science and Space Subcommittee, said Friday that Obama is putting $100 million for the accelerated asteroid mission in the 2014 budget that comes out next week. The money would be used to find the right small asteroid.

(WATCH: Asteroid Has Uncomfortably Close Encounter with Earth)

Nelson said this would help NASA develop the capability to nudge away a dangerous asteroid heading to Earth in the future.

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