Astronomers who surveyed 87 percent of the sky said they had not found Planet Nine yet in the solar system.

Astronomers named Pluto, discovered in January 1930, as the Planet Nine. They did, however, reclassify the celestial body as a dwarf planet.

While astronomers believe that the solar system contains a previously unknown Planet 9, the new search yielded no results.

Researchers uploaded the study, "The Atacama Cosmology Telescope: A Search for Planet 9," in The Astrophysical Journal.

Autumn Colours Throughout The UK

(Photo: Matt Cardy/Getty Images)
ST JUST, UNITED KINGDOM - OCTOBER 14: In this long exposure, light pollution from St Ives casts a orange haze in the night sky, as star trails are traced by planet Earth's rotation, above the mysterious Men-an-Tol, one of the best known megalithic structures in Britain on October 14, 2009 near St Just, England. Locally known as the "Crick Stone", the name Men-an-Tol is said to simply mean 'holed stone' and despite having been considered a significant and popular monument from a very early date, its true purpose still remains a mystery. It is thought to have been used in ancient rituals, local legends claims that if at full moon a woman passes through the holed stone seven times backwards, she will soon become pregnant. Other legends say that passage through the stone will cure a child of rickets and for centuries, children with rickets were passed naked through the hole in the middle stone nine times. Many parts of the UK have been experiencing fine autumnal weather, with longer nights and cooling of temperatures, allowing the changing of season to be fully appreciated.

Astronomers Can't Find Planet Nine Yet Again

Astronomers used data from Chile's six-meter Atacama Cosmology Telescope (ACT) to track the planet.

While ACT is designed to study cosmic microwave background radiation, its high angular resolution and sensitivity make it ideal for this sort of search.

For six years, astronomers studied about 87 percent of the sky from the southern hemisphere. They used multiple ways to analyze the photos to discover faint sources while sacrificing positional information.

"Their search found many tentative candidate sources - about 3,500 of them - but none could be confirmed," the Harvard-Smithsonian Center for Astrophysics, a participating institution in the research, said in a release on March 11.

They added: "There were no statistically significant detections."

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Where is Planet Nine?

According to Gizmodo, the team is 95 percent certain that the new scan will not find a solar system object with the given search properties inside the studied area.

No one knows where Planet Nine is in the sky or if it even exists. Still, its gravitational impact requires it to be within particular limits. The imaginary planet is traveling at the exact moment and in specific directions.

Hence, researchers assume that Planet Nine might be hiding in the solar system's beyond reaches, possibly in the Oort cloud of debris hundreds of astronomical units distant from the Sun.

According to experts, planet Nine would have a mass of five to ten Earth masses and circle the Sun at a distance of 400 to 800 au.

With new telescopes, like the Vera Rubin Observatory in Chile, set to go online in the near future, astronomers may finally have the instruments they need to identify something small and far away. Planet Nine's reality can only be hidden for so long.

History of Planet Nine

Astronomers initially started looking for Planet Nine in 2016, Live Science reported. It was 10 years after Pluto was demoted to a dwarf planet from its position as the solar system's ninth planet.

Many teams have attempted and failed to discover that fictional universe half a decade later. The greatest challenge in the search for Planet Nine is the sheer length of the journey.

That implies normal visible light telescopes have a slim chance of finding the chilly, dark Planet Nine. Instead, astronomers use telescopes like the ACT, which can scan the universe using millimeter wavelengths, a short type of radio wave similar to infrared light.

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