Asteroid Speed

How fast do
asteroids travel?

Near-Earth asteroids close in on Earth at speeds between 10,000 and 70,000 km/h, roughly 10 to 60 times faster than a rifle bullet. Here is what drives those speeds and what they mean for impact risk.

See velocities for upcoming approaches →

Speed in context

Everything in the solar system is moving. Earth itself orbits the Sun at about 107,000 km/h. An asteroid that crosses Earth's orbital path is also moving fast enough to maintain its own orbit - typically 60,000 to 120,000 km/h relative to the Sun.

The speed we care about - the closing velocity - is the difference between the two orbits at the point of encounter. That depends on the angle of approach. A head-on encounter, where the asteroid is moving roughly toward the Sun while Earth is moving away from it, produces high relative speeds. A tail-chase, where both are moving in roughly the same direction, produces much lower relative velocities.

20,000–50,000 km/h

Typical close-approach speed

Relative to Earth at closest approach

~67,000 km/h

Chelyabinsk entry speed

One of the faster recorded entries

~107,000 km/h

Earth orbital speed

Around the Sun

Speed and impact energy

Kinetic energy - the energy released on impact - scales with velocity squared. An asteroid moving at 60,000 km/h carries four times the destructive energy of the same object at 30,000 km/h. This relationship makes velocity one of the two key variables in assessing impact severity, alongside size.

The Chelyabinsk object entered the atmosphere at approximately 67,000 km/h. Travelling at roughly 19 km/s through thickening air, it heated rapidly and disintegrated at around 30 km altitude. The energy released - equivalent to about 500 kilotons of TNT - was large enough to produce a shockwave that broke windows across a wide area, even though the object itself never reached the ground intact.

Objects with lower relative velocities are not necessarily safer - a slow asteroid can still be substantial. But speed amplifies the consequences of any given size, which is why velocity data appears alongside miss distance and diameter in the approaches table on this tracker.

Velocities for upcoming approaches

Sort the table below by velocity to see which upcoming asteroids are moving fastest relative to Earth at their closest approach.

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Hazardous only

Name	Date	Est. Diameter	Miss Distance(LD)	Velocity	Hazard

How close do asteroids get?

Miss distances - from lunar distances to kilometres.

How big are asteroids?

Size classes and what they mean for impact risk.

Next close approach

Live countdown and velocity data for the next flyby.

Impact probability

How speed and size combine to determine impact energy.

Common questions

How fast do asteroids travel?

Near-Earth asteroids typically travel at 10,000 to 70,000 km/h relative to Earth at their closest approach. The average is around 20,000–30,000 km/h. At 30,000 km/h, an asteroid crosses the width of the Moon's orbit (384,400 km) in about 12 hours. The exact speed depends on the orbital geometry at the point of closest approach.

Why do asteroids move so fast?

Asteroids orbit the Sun, and all objects in the inner solar system travel fast enough to resist the Sun's gravity. Earth itself orbits at about 107,000 km/h. When an asteroid's orbit crosses Earth's, the closing velocity between them - which is what we call the asteroid's speed relative to Earth - reflects the difference between their orbital velocities and directions. Head-on approaches produce much higher relative speeds than tail-chase encounters.

Does asteroid speed affect how dangerous it is?

Yes, significantly. Impact energy scales with the square of velocity - double the speed, and the kinetic energy quadruples. A 140-metre asteroid at 70,000 km/h carries four times the destructive energy of the same object at 35,000 km/h. Speed is why even relatively small asteroids can cause substantial damage if they reach the surface. The 2013 Chelyabinsk object entered the atmosphere at around 67,000 km/h.

What is the fastest asteroid to pass close to Earth on record?

Exact speed records are difficult to assign because velocity at closest approach depends on the geometry of each individual encounter, and some fast-moving objects are only discovered after they have passed. Generally, Apollo-class asteroids - which cross Earth's orbit - tend to have the highest relative velocities. Objects entering the atmosphere, like Chelyabinsk (approximately 67,000 km/h entry speed), were travelling at the faster end of the observed spectrum.

How is asteroid velocity measured?

Velocity is calculated from the orbital solution derived from observational data. Astronomers measure the asteroid's position at multiple points in time. The rate of change of position, combined with the known geometry, gives the orbital velocity. For close encounters, Doppler radar from facilities like Goldstone and Arecibo (before its 2020 collapse) can directly measure radial velocity - the component moving toward or away from Earth.