The Objects waiting to become a Dwarf Planet | Quaoar, Orcus, Sedna

Quaoar

                The Quaoar is a body that lies beyond the orbit of Pluto. Quaoar is one of the Kuiper belt object. Quaoar is massive enough to be considered as a dwarf planet, but it has not been classified as such yet. The Quaoar is discovered in 2020 by the American scientists Mike Brown and Chadwick Trujillo of the California institute of Technology at the Palomar Observatory in California. The Quaoar name is given after a creation god of the Native American Tongva Tribe. In 2007, the American astronomer Brown found the tiny moon around the Quaoar, Weywot. The name is given after the sky god, the son of Quaoar.

The Quaoar

                The scientists believed that the Quaoar may be red in colour and coated with water ice. In the distant past of Quaoar, it had an atmosphere with nitrogen, methane and carbon monoxide. Because of low gravity of Quaoar, some of these molecules bled away into space but methane stayed. The solar radiation gradually formed hydrogen chins out of the carbon and hydrogen atoms. These hydrogen and carbon atoms make up methane. This process is the cause for the red colour of Quaoar.

                The average distance between the Quaoar and the Sun is approximately 43.7 AU. The closest distance from the Sun is 41.9 AU and farthest distance is 45.49 AU. That means the Quaoar orbits the Sun in nearly circular orbit. The Quaoar requires 288.83 Earth years to complete one trip around the Sun. The one day on the Quaoar is nearly 9 hours long. But derived from the rotational light curves, its rotation period is measured to be 17.68 hours. As the Quaoar is far away from the Sun at an average distance of 43.7 AU, the Sun light requires 5 hours to reach the Quaoar.

 

Orcus – Anti Pluto

                The Orcus is one of the largest known Kuiper belt object. The Orcus is named after the Roman god of the dead who severely punished those who broke their oaths. On February 17^th, 2004, Orcus was discovered by Michael Brown of Caltech, David Rabinowitz of Yale University and Chad Trujillo of the Gemini Observatory. The orbital properties of Orcus are much similar to the Pluto’s. The Orcus has a moon orbiting around named as Vanth. The moon Vanth was discovered by Michael Brown and T.A. Suer on 13 November 2005. The discovery was announced on 22 February 2007. Like Charon compared to Pluto, Vanth is quite large compared to Orcus and is one reason for characterizing Orcus as the “Anti-Pluto”. If Orcus announced as dwarf planet, the Vanth would be the third largest known dwarf planet moon after Charon and Dysnomia.

The Orcus

                The Orcus is locked in a 2:3 resonances with ice giant Neptune. This means, when the Orcus making two revolutions around the Sun to every three of Neptune’s. This resonance is much like Pluto. But except the phase of Pluto. The phase of orbit of Orcus is opposite from Pluto. This means, when Orcus is at aphelion, the Pluto is at perihelion and vice versa. The inclinations and eccentricities are similar to the Pluto. Because of these contrasts and similarities, along with the moons of both Orcus and Pluto. Because of these reasons the Orcus is called as the “Anti-Pluto”.

                The closest distance between the Orcus and the Sun is 30.3 AU and the farthest distance is 48.1 AU. The Orcus requires 245.19 Earth years to complete one trip around the Sun with orbital inclination of 20.6 ^O to the ecliptic. The astronomer Jose Luis Ortiz and colleagues assuming that the moon Vanth is not tidally locked with the Orcus and according to this assumption they have derived a possible rotation period of about 10.5 hours. So, the day on the Orcus is 10.5 hours long.

 

Sedna

The Sedna: farthest known object.

                On 2020, the scientists found a large planetoid in the outer reaches of the solar system. This planetoid is named as Sedna. The planetoid was named after the Inuit goddess of the sea. The average distance of the Sedna from the Sun is about 85 AU. The Sedna is about three times farthest than the Neptune. As the Sedna is farthest known Trans-Neptunian Object, the Sun light requires 5 Earth days to reach on its surface. The Sedna was discovered by the scientists Michael Brown (Calteach), Chad Trujillo (Gemini Observatory) and David Rabinowitz (Yale University). The astronomer Michael Brown initially given a nickname to Sedna as “The Flying Dutchman” or “Dutch”, after a legendary ghost ship, because the Sedna’s slow movement had initially masked its presence from his team.

Orbit of Sedna

The Sedna has the longest orbital period of any known object in the solar system. The orbital period of Sedna is 11,400 Earth years. This orbital period is comparably very longest among all known bodies of the solar system. The closest distance between the Sedna and the Sun is 76.19 AU (perihelion) and the farthest distance 937 AU (Aphelion). The average orbital speed of the Sedna is approximately 1 km per second. The rotational period of Sedna is 10 hours. The discoverers of the Sedna not found any moon around it. The Sedna’s closest approach to the Sun will come to perihelion around July 2076. This is an opportunity to study the Sedna. This closest approach of Sedna is very important because the next perihelion of Sedna will be 12000 Earth years after.