This image was taken by the Arecibo Radar Telescope in Puerto Rico on April 2010. It shows an asteroid the size of an aircraft carrier on direct interception course with Earth's orbit. The arrival day: November 8. This is its trajectory.
Pretty damn close. In fact, The 400m-wide asteroid called 2005 YU55 will get closer to our home planet than the Moon itself: 201,700 miles. That's 0.85 the distance from our silver satellite. So no, it will not kill us. But it will get close enough to get uncomfortable.
According to NASA, the "trajectory of asteroid 2005 YU55 is well understood," so there's no danger whatsoever. Its gravitational influence will not affect anything on our planet; so don't expect volcanos to go off, tectonic plates to sink into molting magma or tides putting London under the North Atlantic. It will just pass by as scientists observe it using the Goldstone and Arecibo antennas, so expect some asteroid porn in the coming days.
It's just a friendly, slowly spinning spherical asteroid darker than charcoal saying high... I WILL GET YOU THE NEXT TIME! (in 2028). [NASA]