The discovery of a dwarf planet in a region of the solar system previously believed empty may indicate a the existence of a “Super Earth” beyond the reach of the most advanced telescopes.
Scott Sheppard and Chad Trujillo led the team that discovered the existence of a dwarf planet called 2012 VP113. They published their findings in the March 26 issue of the scientific journal “Nature”. At 7.5 billion miles from the sun when it was spotted, the dwarf planet is the 3rd farthest known object in our solar system.
Sheppard works for the Carnegie Institution for Science in Washington, D.C. and Trujillo hails from the Gemini Observatory in Hawaii.
The object was identified from images taken on Nov. 5, 2012 by the Dark Energy Camera located in the U.S. National Optical Astronomy Observatory in Chile. Snapshots of the night sky were taken an hour apart, then the images were compiled into a time-lapse movie that revealed a new body moving among the stars.
The discovery of 2012 VP113 (nicknamed “Biden” after Vice President Joe Biden by researchers, due to the object’s initials) is significant because it is the second object that scientists have discovered in a region of space previously believed to be a wasteland devoid of planets, asteroids, and comets.
A team of scientists including Trujillo discovered the dwarf planet Sedna – the other known object in the region – in 2003. Both Sedna and “Biden” are located in the inner Oort cloud at the outer edge of the solar system. Objects within the Oort cloud are difficult to spot with telescopes because of their distances from the earth. Sedna and “Biden” were both spotted as their orbits drew closest to the sun, allowing sunlight to reflect off their surfaces and bounce back to earth.
The discovery of a second body within the region suggests that it may not be as empty as previously thought – there may be thousands of similar objects, waiting to be discovered.
2012 VP113 is 280 miles across, about half the size of Sedna. (Earth is 7,900 miles across.) Temperatures there average at -430 Fahrenheit, and the planet has a light pink tinge, making it difficult for scientists to spot. The color is caused by radiation, which alters the composition of the ice, methane, and carbon dioxide on the surface.
One of the most intriguing discoveries in relation to VP113 is the similarity of it’s orbit to the orbit of Sedna. Both have elongated, erratic orbits that loop extradinarily far beyond the sun. “Biden”’s orbit can reach a distance of 42 billion miles. The similarity in the orbits of the two objects is most likely cause by the gravitational pull of another, larger, body that is beyond scientists’ ability to see.
Scientists are excited about the possibility of the existence of a “Super Earth” as large as ten times the mass of our planet, whose gravitational pull draws Sedna and Biden into erratic orbits.
“To me,” Mike Brown, a professor of astronomy at the California Institute of Technology, told CNN, “what this discovery really shows is that we are on the verge of finally being able to read the story that Sedna is trying to tell us, and that the next few years should bring a flood of new discoveries in this new region out of the solar system.”