Facts About Eris - The Most Massive Dwarf Planet
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Eris (centre) with its moon Dysnomia (left) |
Eris Profile
Name | Eris |
---|---|
Known Satellite | 1 |
Distance from Sun (avg) | 10.125 billion km (68 AU) |
Radius | 1163±6 km |
Volume | 6.59 × 109 km3 |
Mass | 1.66 × 1022 kg |
Surface area | 17 million km2 |
Gravity | 0.82 m/s2 |
Max Temperature | -217℃ or -358°F |
Min Temperature | −243°C or -405°F |
Length of day | 25.9 hours |
Length of year | 559 Earth days |
Discovered on | January 5, 2005 |
Quick Facts About Eris
- Eris is the largest object in the solar system that has not been visited by spacecraft.
- Eris will be closer to the sun than Pluto in roughly 800 years.
- The atmosphere is highly variable. When it is farther from the sun, its atmosphere freezes and fall like snow on earth.
- When it is at its closest point to the sun, the atmosphere converts back into gas.
- The sunlight takes more than nine hours to reach Eris.
- Its day-length similar to our Earth that is 25.9 hours.
- Its surface is highly reflective, which makes it the second most reflective body in the solar system after Saturn's moon Enceladus.
- The surface can reflect 96% of the light that hits its surface, which enables it to be seen through amateur telescopes.
- It is the ninth most massive body that is directly revolving around the Sun.
- Eris is 27% more massive than Pluto, making it the most massive dwarf planet.
- After its classification as a minor planet, its new designation is 136199 Eris.
Detailed Facts About Eris
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Eris was once recognised as the tenth planet
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Samuel Oschin telescope - Telescope that was used to discover Eris © Wikimedia |
Though, initially, Eris appeared to be larger than Pluto, so NASA considered it as the tenth planet (after Pluto). After the discovery of similar objects, IAU re-classified it along with other objects which have similar characteristics as a dwarf planet in 2006.
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Eris had the nickname "Xena"
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Eris - goddess of strife and discord |
On September 6, 2006, Michael E. Brown, a member of the discovery team, suggested the name Eris after the Greek goddess of strife and discord. Seven days after the proposal, on September 13, 2006, IAU declared the name Eris as the official name for the planet. The reason behind the name was that Eris had been recognised as the planet, so Brown thought that a name from Greek or Roman mythology should be given to it as other planets have.
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Eris was once considered larger than Pluto
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Image of Eris that was used to measure its size captured by Hubble telescope |
The team then measured it again by observing a stellar occultation in Nov 2010. In the stellar occultation, they observed Eris passing in front of a star. So by calculating the time taken by it to pass in front of the star can give a more precise data of its size. The occultation provided the diameter of 2,336 km or 1,451 miles with a plus or minus of 12 km or 7 miles.
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Eris has a small moon
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Artist's impression of Eris and its moon Dysnomia © Wikimedia |
Brown suggested the name Gabrielle for the newly found moon, after the sidekick of Xena in the serial. Later IAU gave Eris its official designation, Brown suggested name "Dysnomia" for the moon, after Eris's daughter who was the Greek goddess of lawlessness. The primary reason behind the name was that he wanted to give it a name that is similar to her wife's name, Diane.
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Eris is located in an extremely dark and cold region
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Objects in the outer solar system © Wikimedia |
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Eris also has a highly eccentric orbit
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Orbit of Eris © Wikimedia |
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