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These are the biggest asteroids and the threats they pose to Earth

NASA scientists have identified more than one million asteroids to date.

The rocky remnants are leftover the early formation of our solar system 4.6 billion years ago.

What are the top five biggest asteroids and do they pose a threat to Earth?

Most of the 1,113,527 asteroids orbit the sun between Mars and Jupiter within the main asteroid belt.

They range in size – from a whopping 329 miles in diameter to a comparatively measly 33 feet across, according to NASA.

Though it is possible that an asteroid could hit Earth one day, the chances are pretty slim as they are so far away.

Astronomers monitor the sky and regularly track asteroids to establish the risk, and we would likely know about an imminent hit years in advance.

A spokesperson for NASA’s Jet Propulsion Laboratory said: “NASA knows of no asteroid or comet currently on a collision course with Earth, so the probability of a major collision is quite small.

“In fact, as best as we can tell, no large object is likely to strike the Earth any time in the next several hundred years.”

NASA is monitoring an asteroid called Bennu which has a 1/2700 chance of impacting Earth between 2175 and 2195.

But as that is a long time off, here are the top five biggest asteroids.

1. Ceres

Two views of Ceres are seen in images acquired by NASA's Dawn spacecraft from a distance of about 52,000 miles .
Two views of Ceres are seen in images acquired by NASA’s Dawn spacecraft from a distance of about 52,000 miles. Reuters

The largest object in the asteroid belt between the orbits of Mars and Jupiter is Ceres.

It was the first asteroid discovered in 1801 and was originally deemed a planet.

It was later reclassified as an asteroid in the 1850s but was reclassified again as a dwarf planet in 2006.

While no longer strictly an asteroid, it takes the number one spot as it measures a whopping 580 miles in diameter.

Ceres is named after the Roman goddess of corn and harvests – and has the same origin as the word cereal.

It was 1,682 Earth days – or 4.6 years – for Ceres to make one trip around the sun.

And it completes one rotation around its axis every nine hours.

2. Vesta

  In this handout from NASA, the giant asteroid Vesta is seen in an image taken from the NASA Dawn spacecraft about 3,200 miles above the surface July 24, 2011 in Space.
In this handout from NASA, the giant asteroid Vesta is seen in an image taken from the NASA Dawn spacecraft about 3,200 miles above the surface July 24, 2011 in Space. Getty Images

Vesta is the largest official asteroid in the main asteroid belt, and the second most massive body.

It was discovered by Heinrich Wilhelm Olbers in 1807.

Vesta is about 329 miles in diameter, accounting for almost nine percent of the total mass of all asteroids.

Spherical in shape, Vesta has separated into crust, mantle and core much like Earth.

3. Pallas

Pallas was named after the Greek goddess of wisdom after it was discovered in 1802.

It measures approximately 318 miles in diameter and makes up about seven percent of the total mass of the asteroid belt.

Unlike other asteroids, Pallas’ orbit is highly inclined at 34.8 degrees making it relatively inaccessible to study.

4. Hygiea

Hygiea comes in fourth place at 270 miles across.

It is a major asteroid in the main belt, but it could soon be considered a dwarf planet due to its almost spherical shape.

If becomes such, it will be the smallest dwarf planet in our solar system.

Astronomer Annibale de Gasparis discovered the asteroid in 1849.

Hygiea is not deemed potentially hazardous as its orbit does not bring it close to Earth.

5. Interamnia

Rounding off the list of the biggest asteroids is Interamnia.

The asteroid spans 217.5 miles in diameter and orbits the sun every 1,950 days – or 5.34 years.

It is not considered viable to explore Interamnia due to its distance from Earth.