Why is Eris a dwarf planet? Eris was originally thought to be the tenth planet in the Milky Way solar system. It is the largest know dwarf planet in existence. Astronomers made the discovery in 2005 at the Palomar Observatory, in California. This discovery was subsequently made through telescopic images from 2003.
It has a diameter of 1,445 miles making it almost identical in size to Pluto but is triple the distance from the sun. Eris revolves around the Sun in an orbital period of 560 Earth years in an elliptical orbit. And it takes Eris 25.9 hours to make one full rotation giving it a length of day very similar to us.
Methane ice covers the surface of Eris. Scientists have estimated surface temperatures on Eris to range from -359°F to -405°F
Moons
Dysnomia is the only moon and it is also one of the largest objects in the Neptunian region with a diameter of approximately sixty-two miles. Ice is the primary component of Dysnomia’s structure.
Why Is Eris A Dwarf Planet And Not A Planet
Eris is classified as a dwarf planet because it does not have the ability to clear its orbit. That ability however is one of the criteria that must be met in order to declare a celestial body a planet. Therefore it is a dwarf planet.
The Wrap Up
In conclusion, Eris is the last of the four dwarf planets in our solar system. Like the others, there is still a lot to discover as there is presently too little known. Accordingly, with time there will undeniably be more information that becomes available as scientific research and study undoubtedly continue.
If you would like to discover more outside of our planetary system, you might enjoy the articles on Extra-Solar Planets.
If you have learned something new or exciting, please let me know in the comment section below.
There is so much more that remains unknown in both space and time. I will keep exploring the possibilities and sharing my experiences with you here.
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Disclosures & Policies
All Images Are Courtesy of NASA
References
NASA. (2021, March 21). Eris. Retrieved from NASA: https://www.britannica.com/place/Eris-astronomy
Learning about space and our solar system is always so cool. Thank you for this article on why is Eris a dwarf planet and not a normal planet! It’s phenomenal that we’re still discovering new planets in our solar system. So when it comes to dwarf planets, we got Eris, Pluto… what are the other two dwarf planets?
Hello Kevin,
Thanks for joining me on my explorations. I appreciate the company. I am also fascinated by what else there is to be discovered.
While there are many Dwarf Planets, we have only five in our Solar System. They are Pluto, Eres, Ceres, Makemake, and Haumea. They are all unique and exciting in their own ways. You can find articles on each of them through the links above.
Have a wonderful day!
This is the first time that I discover about the existence of the dwarf planet Eris, so it was very interesting to read more about it.
I unfortunately don’t quite understand your statement that Eris is classified as a dwarf planet because it does not have the ability to clear its orbit. That ability however is one of the criteria that must be met in order to declare a celestial body a planet. Therefore it is a dwarf planet. Can you please expand and clarify to make it easier to understand. Thank you
Hello Line,
I am new to the knowledge of Eris as well but I am having fun in my explorations.
Yes, to clarify that statement you mentioned…
To be classified as a Dwarf Planet, a celestial object would need the gravitational force required to pull any other object or debris out of its orbital path so that there are no obstructions to its orbit.
Does that make sense? I hope so.
Have a wonderful day!
Great article! It was interesting to learn about Eris and its classification as a dwarf planet. I didn’t realize that it was almost the same size as Pluto, but its distance from the sun and ability to clear its orbit make it a dwarf planet instead. Thanks for sharing this information and explaining why Eris is a dwarf planet. I’m always amazed by the vastness and complexity of our solar system, and it’s fascinating to learn more about these distant objects. Keep up the great work!
Hi Carrie,
Thank you for your compliment. I appreciate your support. You are most welcome, I enjoy the exploration and discovery.
I, too, am fascinated by all that is out there and that remains to be discovered. I hope that you will join me again in the future for more discovery.
Merry Christmas / Happy Hanukkah & Happy New Year To You & Yours.
Have a wonderful Holiday Season!