Detecting asteroids in the solar system's

After a decade of searching, astronomers have discovered the second dwarf planet with orbit far above Pluto, but has yet to explain why the planet is there.

This tiny planet is now called the "2012 VP 113" by the International Asteroid Center, which has an estimated diameter of more than 450km, less than half the size of the "neighbor" dwarf planet. It is called Sedna, discovered in 2003.

Sedna and VP 113 were the first objects to be found in the area of ​​the solar system that had previously been thought to not exist in any planet.

This supposedly desolate area stretches from the outer edge of the Kuiper belt, where Pluto and more than 1,000 other small icy objects, to the cloud of Oort dust with orbit around the Sun farther away Earth orbit about 10 thousand times.

"When Sedna was discovered 10 years ago, it almost redefined what we thought about the solar system," astronomer Scott Sheppard of the Carnegie Institution, Washington DC, said in an interview.

Simulation image of asteroid Sedna.(Source: Reuters)

According to astronomers in the study published in Nature last Wednesday, there is no event in the modern solar system that can explain the existence of Sedna and VP 113.

The 11400-year rotation around Sedna's Sun has a distance of about 76 times the distance the Earth orbits the Sun. The closest point to the Sun that VP 113 has appeared has about 80 times the distance to Earth's orbit - farther than the Kuiper belt almost 2 times.

"According to the current solar system architecture, Sedna and 2012 VP 113 could not be there , " wrote Megan Schwamb, an astronomer at the Sinica Institute in Taipei, Taiwan, writing in an article. Published in Nature.

Computer simulations give some possible scenarios. Lead researcher Chad Trujillo leaned on the idea that a star formed in the same nursery as the Sun, due to the force of gravity, collided and pushed some of the Oort cloud into inside.

Sheppard argues that it is possible that another planet with the least size of Earth would be knocked out of the solar system and bring with it some entities of the Kuiper belt. These planets may still be in the most remote part of the solar system, overshadowed and too isolated to be detected through telescopes or cameras, Sheppard said.

The third option is that the Sun has a companion, an entity that is 5 to 10 times the mass of the Earth, with gravity large enough to make Sedna, VP 113 and possibly about 10 million planets Other dwarfs fall into strange and distant orbits.

"With the discovery of the second dwarf planet, we cannot rule out a hypothesis , " Trujillo said.

It is possible that more objects in the inner domain of the Oort cloud will be discovered in the future.

Astronomers are trying to confirm the existence of six planets like Sedna, discovered last year. This means recording images of asteroids several times a year, or even more, to measure their movement relative to stars.

"They are really hard to find," Trujillo said.

Astronomers believe that there can be up to 150 million dwarf planets like Sedna, with a diameter of about 50 to more than 8000km, both large and in size compared to celestial bodies of the Kuiper belt.