In the last few weeks, we've seen asteroids pass by Earth on multiple occasions. Although these space rocks revolve around the Sun in their own orbit, interaction with a planet's gravitational field can knock them off course and bring them closer to Earth, as per NASA. These encounters can knock asteroids out of the main belt between the orbits of Mars and Jupiter, and send them tumbling in all directions across the orbits of the other planets. NASA now says that as many as two asteroids have been spotted travelling towards Earth in their orbit and are expected to pass by the planet tomorrow, March 27.