A new trans-Neptunian object 2014 UZ224 has been annouced by the discoverers. It’s orbit has a semi-major axis of 109 AU with a current distance of 93 AU in the scattered disc.
Calla Cofield reports in Space.com,
The dwarf planet, called 2014 UZ224, measures about 330 miles (530 kilometers) across and is located about 8.5 billion miles (13.7 billion km) from the sun, NPR reported today (Oct. 11). For comparison, Pluto’s largest moon, Charon, is about 750 miles (1,200 km) in diameter, and reaches a maximum distance of about 4.5 billion miles (7.3 billion km) from the sun.
A year on 2014 UZ224 (the time it takes the dwarf planet to orbit the sun) is about 1,100 Earth years. One Pluto year … is about 248 Earth years.
The object was discovered using the Dark Energy Camera.
A project called the Dark Energy Survey is using observations from the DECam to create a map of the universe that provides information relevant to the study of dark energy. The DES maps have already been used to study dark matter (which makes up about eighty percent of all the mass in the universe but whose exact nature is still a mystery) and to find previously unidentified objects.
Part of the DES includes taking images of a few small patches of the sky “roughly” once per week, according to the mission website, and that’s what made this new discovery possible.
The interesting part of this article tells how undergraduate students made the discovery by analyzing data with software they wrote.
Once again there’s a minor crisis in naming.
The smallest object in the solar system that has earned the title of “dwarf planet” (prior to this new discovery) is Ceres, which lies in the asteroid belt between Jupiter and Mars. Ceres is 590 miles (950 km) across. The object 2014 UZ224 might be too small to be considered a dwarf planet, Gerdes told NPR, but that will have to be decided by the International Astronomical Union (which made the controversial decision to demote Pluto to a dwarf planet). There are four other recognized dwarf planets in the solar system, but scientists think there could be dozens — or even more than 100 — objects that size that have yet to be discovered, according to NASA.
I like it’s easiest to think of solar system distances in terms of light travel time from the sun. It takes sunlight about eight minutes to reach the Earth from the Sun. It’s 43 minutes to Jupiter, over five hours to Pluto on average, and 15 hours to UZ224.
The chart below is based on the semi-major axis of each orbit which you can think of as the average of the maximum and minimum distances from the Sun.
Earth 1.0 AU = 8.3 min Jupiter 5.2 AU = 43 min Neptune 30 AU = 4h10m Pluto 39 AU = 5h25m UZ224 109 AU = 15h08m