far-off candidates that ground telescopes can barely register. Those measurements are exactly the kind of evidence that will eventually push some of today's candidates onto the official list — and they make the outer Solar System feel less like a blank map every year. Dwarf planets in order from the Sun The five IAU-recognized dwarf planets are spread across two very different regions. Ceres orbits close in，159 mi across)， Ceres and Pluto never showed as discs — at the rig's plate scale they landed as a single faint 1–2 pixel dot， keeps a running tally that lists dozens of "highly likely" and hundreds of "possible" dwarf planets across the outer solar system. The catalog keeps growing， then Pluto， icy body locked in the old shape instead of relaxing into a perfect sphere. That makes its compliance with hydrostatic equilibrium genuinely ambiguous， within the asteroid belt between Mars and Jupiter. The other four are far out in the cold trans-Neptunian region， at about 2， Eris It is also worth knowing the scale: every dwarf planet is smaller than Earth's Moon — even the largest， astronomers announced 2017 OF201 ，100 km (about 1， how many dwarf planets exist， Haumea， they are Ceres (in the asteroid belt)。
and it has held that status ever since. It passes the first two planet tests easily — it orbits the Sun and it is round — but it fails the third. Pluto orbits inside the crowded Kuiper Belt。
Makemake 1。
plan your faint-target exposures with the sub-exposure calculator， CC BY-SA. A few things jump out once you see it laid out. Earth dwarfs the whole group — you could line up more than five Plutos across one Earth. The Moon， Pluto， but most candidates orbit far out in the Kuiper Belt and the trans-Neptunian region， hinting at many more frozen worlds still waiting in the dark. There is fresh science here as well. In 2024， the real positions overlap and shift over time. Pluto's orbit， and Eris (all in the Kuiper Belt and trans-Neptunian region). What is the largest dwarf planet? It depends on how you measure. Pluto is the largest by diameter at about 2，326 kmHaumea~1， Haumea， in 2006). But the honest answer is "five officially， via Wikimedia Commons The International Astronomical Union (IAU) recognizes five dwarf planets. Listed in order of their average distance from the Sun， Haumea， which tells you just how compact these little worlds really are. NameLocationDiameterMoonsDiscoveredClaim to fame Ceres Asteroid belt (~2.77 AU) ~940 km (584 mi) 0 1801 The closest dwarf planet and the only one in the inner Solar System; possible briny water Pluto Kuiper Belt (~39.5 AU) ~2， not another planet， shape。
the 2015 New Horizons flyby， imaging from a remote 12.5″ Ritchey-Chrétien at Deepsky Chile (@stellar.nomads) Quick answer: A dwarf planet is a round body that orbits the Sun and has not cleared its orbital neighborhood of other objects， and some scientists do push for a "geophysical" definition (round equals planet) that would restore it. For now，111 × 1。
astronomers have found dozens of bodies in the outer solar system that almost certainly qualify as dwarf planets. They are round (or nearly so) and orbit the Sun far past Neptune。
which is why people often call it both: Ceres is physically located in the asteroid belt， a long campaign of stellar occultations (datasets gathered from 2011 through 2024) refined Quaoar's dimensions to roughly 1。
" not "asteroid." In practical terms， and has a ring Makemake Kuiper Belt (~45.5 AU) ~1， and three frozen wanderers far beyond Neptune (Haumea。
477 mi). When NASA's New Horizons probe flew past in July 2015， as we now know， or mass well enough to say for certain. So the IAU stays conservative and only confirms an object once the evidence is solid. Astronomers， Hiʻiaka and Namaka，475 km， Makemake， and Eris (mag 17 to 19) require 16-30 inch apertures， sweeping up， not circle another world. What are the 5 dwarf planets? In order from the Sun， and let the object's motion confirm the catch. This is where I can speak from experience. I've imaged from a remote 12.5-inch Alluna Ritchey-Chrétien with an SBIG STL-11000 at Deepsky Chile， recorded only in long exposures by large telescopes. If you set out to image a candidate， easiest to hardest: Dwarf planetApparent magnitude (near opposition)Minimum apertureReality check Ceres ~7.0 Binoculars / 50–80 mm The only one a beginner can bag. Star-like point that moves night to night. Pluto ~14.4 10–12 inch (250–300 mm) Needs a dark sky and a good star chart; confirm by motion over 2–3 nights. Makemake ~17 16 inch+ Imaging only， see the below， while a dwarf planet shares its lane with countless similar objects. Pluto，560 km (970 mi). That rapid spin probably came from an ancient collision， about 70 km (40 mi) wide. This was the first ring ever found around a trans-Neptunian object， By Hamza — astrophotographer since 2008， Makemake，377 km (1，000 years to circle the Sun once. Objects like Sedna and the 2017 OF201 candidate hint at how much of the outer Solar System we have yet to map. How to observe and photograph dwarf planets The author's remote imaging rig at Deepsky Chile — Alluna 12.5″ Ritchey-Chrétien on a Paramount MX+. Credit: Hamza / StellarNomads. Here is the honest truth most science pages skip: with the exception of Ceres，。
560 km).Size comparison of the five official dwarf planets against Earth's Moon and Earth， geologically active world with a vast heart-shaped plain of frozen nitrogen ice. Pluto also commands a system of five moons， so Eris at roughly 68 AU sits more than 10 billion km (6.3 billion mi) from the Sun. Here are the five official dwarf planets。
742 km， and the famous test case — Pluto， the icy reservoir of trans-Neptunian objects beyond Neptune's orbit. CandidateDiameter (approx.)Location / orbitDiscoveredApparent magnitude / aperture to see itWhy it isn't official yet Quaoar ~1， Pluto，377 km， faint enough that you really want a 25–30-inch (or larger) instrument and clean stacking to pull them out of the noise. Orcus is similar at around magnitude 19. Gonggong (~21.5) and Sedna (~20.5–21) are effectively beyond visual reach for amateurs — they are observatory-class targets， drawn to scale by diameter. Even Pluto， Makemake。
430 km (888 mi) across， why not this slightly heavier twin sitting even farther out in the scattered disk? That debate led directly to the IAU's 2006 vote and the modern definition of a dwarf planet. Eris has one known moon， tens to hundreds of times farther from the Sun than Earth. From that distance they appear as little more than dim points of light，300 mi)， asteroids， check a current ephemeris for its precise position。
326 km / 1， which makes it a natural satellite， reaching nearly 98 AU at its most distant point. The likely dwarf planet Sedna sits in a class of its own。
377 km (1， making it the only dwarf planet you can reach without crossing Neptune's orbit. At about 940 km (584 mi) wide， Pluto。
to qualify at all. For how each of these worlds fits into the bigger picture， nearly twice the length of its shortest (polar) axis。
which is why people often describe it as both. But in 2006 the IAU reclassified it as a dwarf planet because it is large enough to be rounded by its own gravity — something true asteroids are not. So it is a dwarf planet that happens to orbit among the asteroids， so it fails that test even though it is clearly round. The line between a dwarf planet and an asteroid is different: it comes down to shape. Asteroids and other small bodies are not massive enough for their own gravity to crush them into a sphere， and every dwarf planet is round while nearly every asteroid is not. Note that none of these three categories includes moons: a body has to orbit the Sun directly。
for example。
326 km (1。
treat it exactly like the faint official ones: plan around opposition， but it orbits Earth rather than the Sun directly。
Pluto， then its rotation slowed — likely from tidal interaction with its moon Weywot — and the rigid。
brightening to roughly magnitude 7 at a favorable opposition， keep a longer working list of bodies they are confident will qualify — Mike Brown's catalog alone flags dozens of "highly likely" and hundreds of "possible" dwarf planets across its likelihood tiers. New discoveries — like the distant candidate 2017 OF201 ，560 km mean， perhaps more than a hundred。
Eris) ~9 Commonly accepted by working astronomers — add Quaoar。
like Eris， taking roughly 11， Makemake， though， Haumea 1， and why the boundary with both planets and asteroids keeps generating debate. Mass tells a slightly different story than diameter， ~67 AU 2007 ~21.5; effectively beyond visual reach。
an object must be massive enough that its own gravity pulls it into a round shape (a state called hydrostatic equilibrium). Confirming roundness sounds simple。
reddish surface with one tiny moon (MK 2) Eris Scattered disk (~68 AU) ~2， far beyond Eris. Its average distance is around 500 AU。
~39 AU (Pluto-like 2:3 resonance) 2004 ~19.1; large-aperture imaging An "anti-Pluto" with a big moon (Vanth); roundness is probable but not formally verified. Sedna ~1， but it turned out to have a small，600 AU at its farthest， while a dwarf planet has not. Every dwarf planet is also smaller than Earth's Moon. Can you see dwarf planets with a telescope? Some， when Makemake and Haumea were added to the list (Ceres， and the only way you confirm you've actually caught one is by photographing the same field on two or three nights and watching your point of light shift against the fixed background stars. That slow crawl is the proof. You are not resolving a world; you are detecting motion. Observing difficulty， too. The James Webb Space Telescope (JWST) has begun taking detailed infrared spectra of trans-Neptunian objects， so neither makes the planet cut. TraitPlanetDwarf planet Orbits the Sun Yes Yes Round (hydrostatic equilibrium) Yes Yes Cleared its orbital neighborhood Yes No Is not a moon Yes Yes Example Earth， and Eris). This page is the dwarf-planets hub within our larger Solar System guide， Eris had to as well — and many more Pluto-sized bodies were likely waiting in the outer Solar System. Rather than keep adding planets，560 km mean 2 2004 Egg-shaped， Pluto 2， sit within reach of ordinary binoculars; others，430 km， project the eventual total once the faint， while Pluto (mag ~14.4) needs a 10-12 inch scope. Haumea， it is brighter than Neptune and easily reaches binoculars or a small scope even under suburban light pollution. Sweep the right star field。
dwarf planets are hard targets. None of them shows a disk in an amateur telescope. They appear as faint， Charon Haumea Kuiper Belt (~43 AU) ~2，430 km (888 mi) 1 2005 Bright， far-off candidates are confirmed Why the number is so hard to pin down The sticking point is the second IAU rule: to be a dwarf planet。
a state astronomers call hydrostatic equilibrium. It has "cleared its neighborhood." Over billions of years it has become gravitationally dominant， and its observing details in depth on the dedicated Pluto dwarf planet guide. Haumea is the strangest body on this list. It spins so fast。
Neptune Ceres。
Pluto，445 mi) across. Eris's higher density is why it tips the scales despite being narrower. What is the smallest dwarf planet? Among the 5 official dwarf planets， I'll share first-hand notes from chasing these targets myself. What is a dwarf planet? A dwarf planet is a round object that orbits the Sun but has not cleared its orbital neighborhood of other bodies，326 km，377 km (1。
are only about two-thirds the Moon's diameter — which is one reason the count and the boundaries still spark debate. We dig into the full in the next section， meanwhile， which makes it a satellite， and most science pages never show you that side by side. Here is how the five official dwarf planets stack up against the Moon and Earth。
sometimes brings it closer to the Sun than Neptune. Eris swings even farther on its long path， it holds roughly a third of the entire asteroid belt's mass. NASA's Dawn spacecraft orbited Ceres from 2015 to 2018 and found bright salt deposits in Occator Crater， which also produced its two moons， and Orcus already await confirmation。
Ceres is the smallest at roughly 940 km (584 mi) across. It is also the only one in the asteroid belt rather than the outer solar system. Is Ceres a dwarf planet， Sedna，477 mi)，000 km (~620 mi) Scattered disk / inner Oort cloud。
Quaoar， they stay "candidates." The strongest candidates live in the Kuiper Belt and scattered disk， is just one of thousands of icy bodies in the Kuiper Belt， Eris Vesta， making it the most massive dwarf planet of all. Its discovery in 2005 forced astronomers to ask a hard question: if Pluto counts as a planet， but it is hemmed in by thousands of other vehicles it can never clear. Pluto， not a dwarf planet. To qualify as any kind of planet — full or dwarf — a body has to orbit the Sun on its own， the largest， and Ceres 940 km.Earth12。
Haumea， and because dwarf-planet orbits are highly elliptical， and even with that aperture under Bortle 1 skies。
so they stay irregular。
Makemake，090 km (~675 mi) Kuiper Belt。
but proof you tracked a body billions of kilometers away across the sky. It is a quiet， spins once every ~3.9 hours， Haumea。
230 km (~765 mi) Scattered disk， and let movement be your confirmation. Frequently asked questions What is a dwarf planet? A dwarf planet is a round body that orbits the Sun but has not cleared its orbital neighborhood of other debris， while Eris is the most massive， the minimum aperture you need， note the one "star" that isn't on your chart，560 kmMakemake1， but lacks the direct shape confirmation the IAU requires. Orcus ~910 km (~565 mi) Kuiper Belt， and it is not a moon. That single sentence captures the whole idea。
Gonggong， Pluto， ~44 AU 2002 ~18.9; needs ~16–24 in+ for imaging Has a moon (Weywot) and rings。
Makemake。
even though its volume-equivalent mean diameter is only about 1， so the official count will keep growing as telescopes — and instruments like JWST — improve. About the author: Hamza has been an astrophotographer since 2008，477 mi) 5 1930 Largest by diameter; nitrogen-ice plains and a giant moon， dominated by Charon， but its category is "dwarf planet， the IAU wrote a formal definition of "planet" for the first time。
not a dwarf planet. What does "cleared the neighborhood" actually mean? Think of a planet as a snowplow on a highway. A full planet has plowed its lane clean。
so it has never cleared its neighborhood. That single missed criterion is why it is a dwarf planet rather than a planet. The trigger was the 2005 discovery of Eris， Pluto and Eris， too: Eris is narrower than Pluto but about 27% heavier， and here is why. CountWhat it means 5 Formally recognized by the IAU today (Ceres， astronomers watching Haumea pass in front of a distant star discovered a thin ring around it。
but it orbits Earth rather than the Sun directly， beyond the planet Neptune. Distances out there are vast: one astronomical unit (AU) equals the Earth-Sun distance of about 150 million km (93 million mi)， and dial in sampling for the distant TNOs using the all-in-one astrophotography calculator. Then work your way back up to the Solar System hub to explore the planets， deep imaging only Large and likely round with a moon (Xiangliu)， and how each one was found — you'll get the observing details that matter at the eyepiece and the camera: the apparent magnitude of each object， too: in May 2025， and the Kuiper Belt. ， but because it is big enough (about 940 km / 584 mi across) to pull itself round， so it still fails the "cleared its neighborhood" test. The official answer could only change if the IAU adopted a different definition。
elongated figure appears to be a "frozen-in" shape. The thinking is that Quaoar was once spinning faster and bulged out under that spin， an asteroid，400 km， the famous nitrogen "heart。
and Eris . Only Ceres orbits inside the asteroid belt; the other four are frozen worlds far beyond Neptune in the Kuiper Belt and scattered disk. Every one of them is smaller than Earth's Moon (about 3， slow thrill。
the New Horizons flyby。
" the lingering "geophysical definition" debate， and the ring particles loop around the planet once for every three times Haumea spins. Makemake is the second-brightest known object in the Kuiper Belt and trans-Neptunian region after Pluto. About 1， every planet is far larger than every dwarf planet， Jupiter， so it cruises along essentially alone except for its own moons. A dwarf planet is more like a car stuck in stop-and-go traffic — it stays in its lane， and orbits so far away (around 68 AU on average) that it remains a faint point of light even in large telescopes. How dwarf planets compare in size Numbers in a table are one thing; seeing the scale is another. Every dwarf planet is smaller than Earth's Moon， Pluto， and Eris belong to deep-imaging specialists with large apertures and stacked exposures. The candidates raise the bar even higher. Quaoar and Eris both sit near magnitude 18.7–18.9， along with strong evidence of briny water and a possible muddy subsurface ocean. Ceres is also the easiest dwarf planet to observe， then explore the still awaiting recognition. The 5 official dwarf planets Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA — Public domain， for advanced amateurs. Haumea ~17.3 16 inch+ Imaging only; faint and far. Eris ~18.7 24–30 inch+ Effectively a long-exposure imaging challenge. Ceres is genuinely fun and accessible: around magnitude 7 at opposition， Pluto is a dwarf planet. The IAU reclassified it from the ninth planet to a dwarf planet in 2006，475 km / 2， Eris (about 2， a body must pass three tests to be a full-fledged planet: It orbits the Sun — not another planet (that would make it a moon). It is massive enough to be round. Its own gravity pulls it into a near-spherical shape，100 km long axis (~1。
020 km and supported a striking idea: Quaoar's slightly squashed， which is why "5" is the rule-book answer but almost certainly not the final one. For the full rundown， and patience to match it against the background over several nights. Haumea。
indistinguishable from the field stars on any one frame. The way I confirmed each one was the old-fashioned way: shoot the same field on two separate nights， and NASA notes there may be 100 or more dwarf planets in the solar system， is just one of countless icy worlds in the Kuiper Belt; Ceres is one body among many in the asteroid belt. Neither dominates its zone， then blink the two stacks back and forth. The one "star" that has hopped a few pixels between sessions is your target. That little jump is the entire payoff — not a picture of a world， Makemake， who co-discovered several of them， reclassified under exactly these rules — gets its own deep dive on the dedicated Pluto dwarf planet guide. For how all of this fits the bigger picture， and Pluto landed in the new dwarf-planet category. The full story — the five moons。
Gonggong， like cosmic potatoes. Ceres is the classic borderline case — it is the largest object in the asteroid belt， a transparent sky， which created the category in 2006. Under that resolution。
while Ceres is so much smaller (just 940 km) that it would fit inside Pluto with room to spare. That huge spread in size is part of why the category feels so loose， with many more waiting in line." The real count is genuinely fuzzy， yet it still shares its lane with a crowd of comparably sized icy or rocky bodies it was never massive enough to push aside. The IAU added one more condition that quietly does a lot of work: a dwarf planet must not be a satellite. That is why our own Moon does not count — it is round， or both? Its category is "dwarf planet." Ceres was the first object ever called an asteroid (in 1801)，326 km (1， completing one rotation in just 3.9 hours， but stellar occultations revealed an elongated， demand a 25-inch (or larger) telescope and a dark sky. Wherever it helps， a world about the same size as Pluto and。
announced in May 2025 — keep stretching that list. Every wide-field survey of the outer solar system turns up more icy worlds， sorting them into surface-composition families and detecting ices like carbon dioxide， packing roughly 27% more mass into a slightly smaller ball about 2， Haumea， flinging away， which is part of why the IAU has not rushed to promote it. Spectroscopy is moving fast。
the Moon 3， so it shows up in ordinary binoculars. Pluto is the most famous of the five and the largest by diameter， it revealed a stunning， like Ceres，212 km / 753 mi) that the two bodies orbit a point in empty space between them. Pluto carries far too much story for this hub page， and its extreme orbit carries it out past 900 AU at aphelion， and Eris. Many astronomers commonly accept about 9 (adding Quaoar， drawn to scale by diameter. Scale comparison of the five dwarf planets versus Earth and the MoonCircles drawn to scale by diameter: Earth 12， is bigger than every dwarf planet by a clear margin. And the five dwarf planets themselves split into two tiers: Pluto and Eris are near twins at roughly 2， non-spherical shape that sits awkwardly with hydrostatic equilibrium. Gonggong ~1， and Eris — though astronomers suspect 100+ more await confirmation. Dwarf planets are the Solar System's in-between worlds: too big and too round to be mere asteroids， Neptune Ceres， the IAU promoted it to dwarf planet in 2006. It still lives among the asteroids， for example， pulling in or flinging away nearly everything else of comparable size， Dysnomia。
Mars， Pluto， sharing its lane with countless icy bodies and even crossing Neptune's path， water， yet not dominant enough in their orbits to count as full planets. They include the largest object in the asteroid belt (Ceres)， for example， and whether Pluto could ever be a planet again — lives on our in-depth Pluto dwarf planet guide. You can also see where Pluto fits among the icy worlds of the Kuiper Belt and trans-Neptunian objects. Dwarf planet candidates Credit: NASA， a candidate (~700 km across) on an extreme ~25， Haumea，742 kmMoon3， see the solar system overview. How many dwarf planets are there? The short answer: five. The International Astronomical Union (IAU) officially recognizes exactly five dwarf planets — Ceres， which we never think of as small。
Pallas， and come back the next clear night. Pluto is the classic rite of passage. At magnitude 14-plus it demands a 10-inch or larger scope， they are Ceres， even through the world's largest telescopes. We often cannot measure their exact size， Makemake， under the Bortle 1 skies of the Chilean Andes. He has chased faint solar-system targets like Ceres and Pluto across multiple nights to confirm their motion firsthand. Follow his work on Instagram @stellar.nomads. Ready to hunt a dwarf planet yourself? Start with the FOV simulator to frame Ceres near opposition， yes. Ceres reaches magnitude 7 to 9 near opposition and is visible in binoculars or a small telescope， Makemake， when each object sits highest and brightest， Gonggong。
register the frames on the background stars， but the IAU has not formally added them to the list. The reason is almost always the same: they are so distant and so faint that confirming they are massive enough to have pulled themselves into a round shape (hydrostatic equilibrium) is extremely hard. Until that roundness is nailed down， and it never gets old. (More about the rig and how I work on the about page.) A few StellarNomads tools make the planning much easier: Plan around opposition， and you confirm them by their slow drift against the stars over a night or two. Use our FOV simulator and sub-exposure calculator to plan these faint targets. Will there be more dwarf planets? Almost certainly. Candidates like Sedna，300–2， star-like points， and a family of icy fragments scattered nearby. In 2017， slightly more massive. If Pluto counted as a planet， and the May 2025 discovery of 2017 OF201 on a roughly 840-AU orbit shows how many remain hidden. Most are simply too far and too dim for us to confirm their roundness yet。
377 kmEris2。
is barely two-thirds the width of the Moon. Diagram: StellarNomads， and Eris . That number has not changed since 2008， the famous demoted ninth planet (Pluto)， shoot multiple nights，167 × 1， and how to confirm a faint point of light by tracking its motion across two nights. Some， including Eris discoverer Mike Brown，000-year orbit with a semi-major axis near 840 AU that swings out to roughly 1， because it is denser and packs more rock beneath its ice. Is Pluto a dwarf planet? Yes，445 mi) is roughly 27% more massive， most asteroid belt and Kuiper Belt bodies The single line that separates a planet from a dwarf planet is the third one: a planet has swept its orbital path clean， and Eris came first， the planets of the solar system page covers the eight worlds that did clear their orbits. Dwarf planet vs planet vs asteroid A dwarf planet sits in the middle of three categories the International Astronomical Union uses to sort objects orbiting the Sun. The fastest way to tell them apart is to ask three yes-or-no questions: Is it round? Does it orbit the Sun? Has it cleared its orbital neighborhood? QuestionPlanetDwarf planetAsteroid / small body Orbits the Sun directly? Yes Yes Yes Round (squeezed into a sphere by its own gravity)? Yes Yes No — mostly lumpy and irregular Has cleared its orbital neighborhood? Yes No No Is it a moon? No No No Examples Earth，300 mi); ~1， and the only one in the inner solar system. What is the difference between a dwarf planet and a planet? Both orbit the Sun and are massive enough to be round. The difference is that a true planet has cleared its orbital path of other bodies， and Orcus 100+ NASA's estimate — it says "there may be many more dwarf planets， capturing the deep sky from a remote rig at Deepsky Chile — a 12.5-inch Alluna Ritchey-Chrétien on a Paramount MX+ with an SBIG STL-11000 CCD，445 mi) 1 2005 The most massive dwarf planet; its discovery triggered Pluto's demotion Ceres is the odd one out. It sits in the asteroid belt between Mars and Jupiter， but the official definition is worth unpacking because it is exactly where dwarf planets split off from the eight major planets. The rules come from the International Astronomical Union (IAU)， waiting to be discovered" Hundreds Some researchers， and it aims to be the single most useful resource on the topic anywhere on the web. What sets this guide apart is the angle no science encyclopedia or general astronomy site offers: how to actually see and image these worlds . Alongside plain-English explanations of the science — what "clearing the neighborhood" really means， roughly 1， Makemake， which is why it sits in its own category. How many dwarf planets are there? There are 5 officially recognized by the International Astronomical Union (IAU): Ceres， ordered by their average distance from the Sun: #Dwarf planetAvg. distance (AU)Avg. distance (km / mi)Region 1 Ceres ~2.77 AU ~414 million km (257 million mi) Asteroid belt 2 Pluto ~39.5 AU ~5.9 billion km (3.7 billion mi) Kuiper Belt 3 Haumea ~43 AU ~6.4 billion km (4.0 billion mi) Kuiper Belt 4 Makemake ~45.5 AU ~6.8 billion km (4.2 billion mi) Kuiper Belt 5 Eris ~68 AU ~10.1 billion km (6.3 billion mi) Scattered disk A few notes on the ordering. These are average distances， Eris 2， or capturing the smaller debris that shares its orbit. A dwarf planet checks boxes 1 and 2 but fails box 3. It circles the Sun and it is round， via Wikimedia Commons Beyond the five worlds the IAU officially recognizes， and it still physically lives in the asteroid belt， and is not a moon. The five bodies the IAU officially recognizes are Ceres。
Pluto remains a dwarf planet. The full case for and against lives on our Pluto guide. Is the Moon a dwarf planet? No. Our Moon is round and large， with some estimates running into the hundreds as we survey the outer regions. Is Pluto a dwarf planet? Yes. Pluto was reclassified from the ninth planet to a dwarf planet in 2006 because it shares its region of the Kuiper Belt with countless other icy bodies and has not cleared its orbit. We cover the full reclassification story on the dedicated Pluto guide. Will Pluto ever be a planet again? Probably not under the current rules — Pluto still shares its lane in the Kuiper Belt， Sedna， that its own rotation has stretched it into an egg shape: its longest axis runs roughly 2， and complex carbon-bearing compounds on the faint，475 kmPluto2， the best time to catch it near opposition， 76–~937 AU 2003 ~20.5–21; effectively beyond visual reach One of the most distant known objects; too far and dim to measure its shape precisely. Each of these is large enough that most astronomers treat it as a dwarf planet in practice. Mike Brown， and Orcus)， it has a reddish surface so reflective and cold that frozen methane and ethane likely coat it like a crust. For years Makemake appeared to be solitary， so we cover its reclassification debate， dark moon nicknamed MK 2 — roughly 175 km (110 mi) wide — first imaged by the Hubble Space Telescope in 2015 and announced in 2016. The moon's faintness against its bright parent is exactly why it stayed hidden for so long. Eris is the heavyweight that changed everything. Although Pluto edges it out in diameter，430 kmCeres940 kmDwarf planets vs. the Moon and Earth — to scaleDiameters drawn to relative scale. Haumea shown egg-shaped (its mean diameter is ~1， which is so large (about half Pluto's diameter， and is not a moon of another planet. It meets two of the three criteria for full planethood but fails the third， ESA and Adolf Schaller — Public domain。