NASA has labeled an asteroid that is currently heading towards Earth as "potentially hazardous". However that doesn't mean it's going to hit the planet.
For an asteroid to be considered "potentially hazardous," it must be classified as a "Near-Earth Object" (NEO), and for an asteroid (or comet) to be a NEO, it needs to "approaches our planet less than 1.3 times the distance from Earth to the Sun", per NASA.
For another perspective on just how far away that is, the distance between Earth and the moon is around 240,000 miles, the distance between Earth and the Sun is 92,900,000 miles. As for the asteroid that is approaching Earth, 2021 NY1 is estimated to be between 427 and 984 feet in diameter, and it will come within 930,487 miles of Earth. The asteroid is moving at 21,000 miles per hour despite its large size and is expected to pass by our planet safely.
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