At the edge of the solar system, far beyond Neptune, a mysterious collection of worlds
can be found, worlds that have only been discovered in the last few decades or so.
These are the solar system's small wonders, the distant and icy dwarf planets.
In 2006 the international astronomical Union or IAU made a highly controversial decision
to place Pluto into a new category, making it the first of the Dwarf planets.
This, as many of you watching will agree, did not go down well, and still to this day,
some continue to consider Pluto as the solar system's ninth major planet.
One of the reasons Pluto was reclassified, according to the IAU, is because it hasn't
cleared its neighbourhood.
It still shares its space with many other objects in a distant region called the Kuiper belt.
This doughnut-shaped area just beyond the orbit of Neptune consists of comets, asteroids,
and many other Pluto sized objects.
Meaning that Pluto is far from alone in the Dwarf planet category.
But how many more of these icy wonders are lurking out there, and how many of them have
been officially confirmed as dwarf planets?
Currently, the IAU officially classifies only five celestial bodies in our solar system as dwarf planets.
Astronomers have, however, identified many other objects that are being considered for
the category, and it's even estimated that hundreds or possibly thousands more may exist,
scattered throughout the distant regions of the solar system.
What these elusive worlds look like is still a mystery.
Most of the images we have of them show only grainy white dots.
But due to the success of the New Horizons mission, we do at least know precisely what
Pluto looks like, and so other dwarf planets found throughout the Kuiper belt may share
similar features.
The only other confirmed dwarf planet we have closely photographed so far is Ceres, which
exists within the inner solar system, between Mars and Jupiter, in an area called the asteroid belt.
But to really see how bizarre dwarf planets can be, we need to travel beyond what we have
already explored, deep into the icy fringes of the solar system.
Come with me, as we travel beyond the major planets and into the mysterious region that
is the Kuiper belt.
Let me know in the comment section below which is your favourite dwarf planet and if you
enjoyed your journey and would like to support my channel, then tap the like button and consider
subscribing for many more incredible adventures across the universe.
Discovered in 2004, this unusual egg-shaped dwarf planet has been named Haumea.
Everything that we know about Haumea has come from observations made via Hubble and ground-based
telescopes back on Earth, and this is the best image ever taken of it.
Haumea is 43 times as distant as the Earth is from the Sun, and to give you an example
of how far away that is, it takes sunlight approximately 8 minutes to reach Earth, whereas
to reach Haumea, it takes 6 hours.
The unusual shape is thought to be a result of its rapid rotation, which distorts Haumea
into an oval rather than a sphere, giving it that deformed egg-shaped look.
It is one of the fastest spinning large objects in the Solar System, completing one rotation
in only 4 hours, which means that one day on Haumea is only 4 hours long.
The strange ring surrounding it is made up of icy debris and was discovered when the
dwarf planet passed in front of the light of a distant star in 2017 and orbiting Haumea,
you will also notice two small moons named Namaka and Hi'iaka.
What caused Haumea to spin so rapidly and gain an icy ring is still a mystery, but scientists
think that it may be the result of a large collision that occurred billions of years ago.
Haumea isn't the only official dwarf planet lurking in Pluto's neighbourhood, however,
because there is an impressively bright object that has also been discovered.
Pluto is the brightest object in the Kuiper belt visible from Earth, but the second brightest
in this region is the mysterious red dwarf planet named Makemake.
First observed in 2005, Makemake holds an important place in the history of the solar
system because it was one of the worlds discovered that prompted the IAU to reconsider the definition
of a planet and create the group now known as the Dwarf planets.
Very little is known about Makemake, but It does appear to be a reddish-brown colour,
similar to parts of Pluto, suggesting that its surface is covered in frozen methane and
ethane, possibly in the shape of small pellets.
Like Haumea, Makemake has never been observed at close range due to its incredible distance
from the Sun, a journey that takes light 6 hours and 20 mins to reach it.
This image taken by Hubble is one of the best views we have of the distant dwarf planet,
and although it doesn't reveal much, if you look carefully, there is another mysterious
object barely visible just above the bright dot that is Makemake.
This faint dot is a tiny, dark moon nicknamed MK2 that evaded detection for more than a
decade, hiding in the glare of its parent.
To get to the next and last official dwarf planet, we need to travel even further, all
the way to the edge of the Kuiper belt.
Discovered in 2005 by the same team that discovered Makemake, this dense dwarf planet named Eris
was briefly thought of as the 10th planet in the solar system.
Because of Its striking similarities to Pluto, the discovery of Eris ended up playing a large
role in the eventual reclassification of Pluto’s planetary status.
A debate that, as I mentioned before, still continues today in the science community and in public.
Some of you may agree more with an earlier plan to increase the number of planets in
the solar system from nine to twelve.
Seeing Pluto and its moon Charon recognised as a twin planets, and Ceres and Eris granted
entry to the major planet category.
But that early idea was met with opposition, and so the dwarf planet classification was
eventually created.
Eris is estimated to hold around 28% more mass than Pluto, despite being smaller in size.
It is the farthest officially confirmed dwarf planet from the Sun, located on the outer
edge of the Kuiper belt, in a region called the scattered disk.
It is so far away, in fact, that it takes sunlight more than nine hours to travel to
this mysterious world.
Since Eris is so far away, no surface details can be seen, but astronomers have detected
the presence of methane ice and believe Eris would likely look something similar to Pluto.
This image taken by Hubble reveals that Eris also has at least one moon, named Dysnomia,
the second-largest moon to a dwarf planet, after Pluto’s Charon.
As it stands, the IAU officially only recognise Pluto, Ceres, Haumea, Makemake and Eris as
dwarf planets.
There are, however, four more mysterious objects that the majority of the scientific community
recognise, but are not yet officially confirmed.
These are Orcus, Sedna, GongGong and Quaoar.
The otherwise unofficial dwarf planets of the solar system and the worlds that we will
visit in part 2 of our journey into the Kuiper belt.
With newer technology becoming rapidly available and exploratory missions gathering more data
on the solar system, our understanding of dwarf planets is slowly increasing.
Whether Pluto, Eris, or any other dwarf planet discovered so far should or shouldn't be classified
as a true planet means nothing when you begin to discover how fascinating these small wonders
beyond Neptune can be.
But one thing is for sure, the discovery of dwarf planets such as Haumea, Makemake and
Eris prove that Pluto isn't the only fascinating world in the Kuiper belt that deserves a future visit.
I hope you enjoyed this video.
If you did, then please tap the like button and subscribe.
If you want to continue exploring our magnificent universe, then why not watch this video about
an undiscovered large planet nine candidate that may be lurking at the edge of the solar system?
Thank you so much for watching, and I hope to see you all next time.