European Space Agency (ESA) issued a fresh challenge to amateur astronomers from all around the world: to spot the mystery asteroid that will make a close approach to Earth. 

ESA is calling space rock "2015 RN35" a Christmas asteroid. On December 15, it will approach Earth quite closely at around 430,000 miles (686,000 kilometers). It is just under the distance to the moon and back.

ESA Encourages Amateur Astronomers to Take Photos of the Asteroid

ESA makes the challenge to spot the Christmas asteroid to mark the release of their new asteroid toolkit. 

Spotting the Christmas asteroid will give skywatchers an exciting opportunity because even if astronomers know that 2015 RN35 will safely pass Earth, there are very few facts known about the said asteroid.

For instance, nobody knows what comprises the asteroid. According to ESA, no one is sure of its makeup, as well as its precise size. Likewise, no one is certain if it is revolving on its axis or even the facts about its orbit.

The space agency challenges amateur astronomers to take pictures of the asteroid. According to ESA, telescopes 30 cm and larger should be able to see the asteroid. 

The agency said that they are eager to see the photos taken by amateur astronomers from all around the world.

According to Mashable, the 2015 RN35 has a visual magnitude under 14, similar to that of Pluto. The best viewing of the asteroid is when it's closest to Earth, particularly for those in the Southern hemisphere.

However, Europe will get a chance to view the Christmas asteroid over the following days.

Unfortunately, the countries in the Northern Hemisphere might not be able to see the Christmas asteroid at all.

If you will see it, ESA encourages you to post your findings with the hashtag #ESAChristmasAsteroid. You can include some personal information as well as where you are. You can post your photos and findings on Twitter, Facebook, Instagram, or Reddit.

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2015 RN35 is About the Size of the Great Pyramid of Giza

The Christmas asteroid has an estimated size of between 200 to 460 feet (60 and 140 meters). This means that it's about the size of the Great Pyramid of Giza, according to Space.com.

In a statement, ESA wrote that the asteroid isn't well known. Similarly, the space agency said that it doesn't know its composition. 

According to Space.com, the same uncertainty applies to hundreds of thousands of mid-sized asteroids around Earth. 

While these mid-sized space rocks may not cause the same kind of devastation associated with massive asteroids, they could still cause a great deal of damage to certain areas if they impact Earth. 

With this, astronomers are especially interested in asteroids like the 2015 RN35 which are classified as Near-Earth Objects (NEOs). 

The study of such asteroids can grant insights into a class of objects that present a potential risk of impact, or the so-called Potentially Hazardous Objects (PHOs).

According to Mint, asteroids are small, rocky chunks of rocks and minerals that orbit the Sun. Since they are smaller than planets, they are also called minor planets.

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