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Solar wind and other particles from the sun could give us an early warning of space rocks heading for Earth, researchers have found.

They say changes in the solar wind, plasma and other types of particle could give away the location of rocks currently missed.

They say it could help spot smaller rocks like the 2013 Chelyabinsk meteor impact in Russia, which injured 500 people and caused significant property damage.

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Changes in the solar wind, plasma and other types of particle could give away the location of rocks currently missed - such as the meteor that blazed across southern Urals in February.

The findings were presented at the 47th annual meeting of the American Geophysical Union in San Francisco. 

Huge near-Earth objects (NEOs) that circle the sun are often trailed by smaller space rocks and ultrafine dust, and the Earth's gravitational pull can bring the smaller objects directly towards the planet.

Even if they are heading straight for Earth, 'you will never see it in a telescope,' study co-author Hairong Lai, a space physicist at University of California, Los Angeles told LiveScience. 

When meteoroids randomly collide with the medium-size rocky bodies in the dust cloud around an asteroid, fine dust is created. 

Photons ping the surface of the fine dust particles, knocking off electrons and leaving the dust positively charged, Wei said. 

As a result, the stream of particles spewing from the sun, called solar wind, interacts with the charged dust and creates a spike in the magnetic field. 

Several spacecraft in the solar system have onboard magnetometers that can detect these magnetic signatures of collision.

By using data from multiple spacecraft on the size and scale of the magnetic field perturbations, along with previously derived data on the speed and characteristics of known interstellar bodies, the team can calculate the size and shape of a trailing debris cloud.  

THE CHELYABINSK METEOR

A meteor that blazed across southern Urals in February was the largest recorded meteor strike in more than a century.

More than 1,600 people were injured by the shock wave from the explosion, estimated to be as strong as 20 Hiroshima atomic bombs, as it landed near the city of Chelyabinsk.

The fireball measuring 18 meters across, screamed into Earth's atmosphere at 41,600 mph. Much of the meteor landed in a local lake called Chebarkul.

Other than the latest find, scientists have already uncovered more than 12 pieces from Lake Chebarkul since the February 15 incident. 

However, only five of them turned out being real meteorites. 

The team has already found that Asteroid 138175, which circles the sun roughly every 368 days, may have tens of thousands of small but deadly objects in its orbit that may pose a threat to Earth.

In contrast, Asteroid 308635, which circles the sun every 455 days, doesn't carry much rocky debris in its wake, Wei said.

Astronomers have identified just 1 percent of these space rocks lurking in the solar system; the objects are usually less than tens of meters wide

Dramatic dash-cam footage of meteor explosion in Russia