https://www.youtube.com/watch?v=MHsDI83dZ_s Eris is presented as a “tenth planet”–candidate whose discovery forced astronomers to redefine the word **planet**, demoting Pluto and creating the modern category of dwarf planets.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Detailed outline of the video - **Opening & setup (0:00–1:30)** - Recaps the long‑standing picture of a neat solar system of nine worlds and introduces a newly found distant object that would trigger an “identity crisis” for the solar system.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Frames Eris as a tiny drifting point of light on archival images whose discovery would “start a war” over the meaning of planet.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Survey and discovery of Eris (1:30–4:15)** - Describes the Palomar survey by Mike Brown, Chad Trujillo, and David Rabinowitz using the 1.2 m Samuel Oschin telescope and automated software to find trans‑Neptunian objects (TNOs).[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Notes earlier successes (Quaoar, Orcus, Sedna) and Brown’s conviction that there “had to be a tenth planet,” prompting him to re‑examine older data.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - On 5 January 2005, Brown identifies a faint, slow‑moving object in images from 21 October 2003, provisionally labeled 2003 UB313, immediately recognizing its significance.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Haumea controversy and going public (4:15–5:00)** - Explains that another team announced Haumea after using Brown’s public logs, pushing Brown’s group to announce two major outer‑solar‑system objects on 29 July 2005: Haumea and the body later named Eris.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Mythological naming and “golden apple” analogy (5:00–6:05)** - Relates the Greek myth of Eris, goddess of strife, who throws a golden apple marked “For the fairest,” leading to the Trojan War, and compares the celestial Eris to that disruptive apple in astronomy.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Introduces the core problem: Eris appears larger and 27% more massive than Pluto, forcing a crisis about how many objects should count as planets.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Redefining “planet” and IAU debate (6:05–9:00)** - Presents the logical dilemma: if Pluto is a planet, Eris must be; if Eris is, what about Makemake, Haumea, Sedna, and other big TNOs.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Describes the 2006 International Astronomical Union (IAU) meeting in Prague where “what is a planet?” is formally debated and voted on for the first time, splitting astronomers into two camps: geophysical vs dynamical definitions.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Competing definitions & final IAU vote (9:00–11:00)** - Geophysical camp: any body in hydrostatic equilibrium (nearly round under its own gravity) should be a planet, which would include Pluto, Eris, Ceres, and many others.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Dynamical camp: a planet must dominate its orbital zone and have “cleared the neighbourhood” around its orbit.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Notes the controversial vote with only 424 of 2,500 attendees present, passage of Resolution 5A (orbit Sun, be round, clear neighbourhood), creation of the “dwarf planet” category, and defeat of a follow‑up resolution that would have made dwarf planets a subclass of planets, officially leaving eight planets.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Mentions criticisms: ambiguous “cleared neighbourhood” wording and Sun‑centric criterion that excludes exoplanets from the definition.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Naming Eris & aftermath (11:00–12:10)** - Brown’s team chooses the name Eris, formally accepted in September 2006, cementing its role as a symbol of discord.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Notes that Ceres benefits by being elevated from asteroid to dwarf planet.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Outer region & Eris’s orbit (12:10–14:05)** - Explains that Eris resides not in the main Kuiper Belt but in the scattered disc, a sparse population of icy objects on extreme, Neptune‑scattered orbits.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Details Eris’s 557‑year orbital period, perihelion ~38 AU, aphelion ~98 AU, and 44° inclination, giving it a steep, highly elongated orbit that carries it far above and below the ecliptic.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Size, mass, and density (14:05–15:35)** - Recounts the 2010 stellar occultation that pinned Eris’s diameter at about 2,326 km, slightly smaller than Pluto, contradicting earlier size assumptions.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Explains that Eris’s 27% greater mass in a slightly smaller volume yields a higher density (2.43 g/cm³ vs Pluto’s 1.85 g/cm³), implying a rock‑dominated interior with a thinner ice mantle.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Surface, albedo, and atmosphere cycle (15:35–17:10)** - States that Eris has an exceptionally high Bond albedo (~0.99) and discusses the idea of atmospheric collapse: a nitrogen‑ and methane‑rich atmosphere that freezes out as frost at aphelion and re‑sublimates as Eris returns sunward.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Mentions James Webb observations of methane isotopes that may hint at geothermal processes in the interior.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Discovery and properties of Dysnomia (17:10–19:00)** - Describes the 2005 Keck adaptive‑optics detection of Eris’s moon, giving the key leverage to measure Eris’s mass via Dysnomia’s 16‑day circular orbit.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Notes Dysnomia’s size (about 25% of Eris’s diameter), tidal locking, very dark surface compared to Eris’s bright frost, and likely formation via a giant impact that stripped volatiles.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Explains the naming of the moon as Dysnomia, Eris’s mythological daughter and personification of lawlessness.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Legacy, “Pluto killer,” and three‑zone solar system (19:00–end)** - Reflects on Mike Brown’s “Pluto killer” nickname, arguing the real legacy is clarifying Pluto’s kinship with many icy dwarf planets beyond Neptune.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Presents a tripartite view: four inner terrestrial planets, four gas/ice giants, and an outer swarm of icy dwarf planets like Pluto and Eris in the trans‑Neptunian region.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Emphasizes that Eris is the most massive unvisited object in the solar system, with a proposed flyby taking ~25 years, and concludes that its discovery resolved one debate while opening many new questions.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Individuals mentioned: roles and contributions The video only names a small set of real people explicitly. ## Mike Brown - **Role in the video** - Lead astronomer of the Palomar survey team that discovered Eris (2003 UB313), as well as earlier TNOs like Quaoar, Orcus, and Sedna.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Quoted on the need for a tenth planet and on the choice between “adding planets or subtracting one,” and later nicknamed the “Pluto killer.”[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Contributions (from the video’s content and references)** - Organized the wide‑field TNO search using the Samuel Oschin telescope and developed software to find slow‑moving distant objects, then manually re‑inspected data to catch Eris.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Led the work that used Dysnomia’s orbit to measure Eris’s mass precisely, showing it is more massive than Pluto and forcing the IAU to confront the planet definition.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Biographical notes (high‑level)** - Identified as head of the discovery team in the video’s narrative, working out of Palomar Observatory in California.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Chad Trujillo - **Role in the video** - Named as one of the three astronomers (with Brown and Rabinowitz) behind the Palomar survey and the discovery of Eris.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Contributions** - Part of the team that systematically searched the outer solar system for TNOs, contributing to discoveries like Quaoar, Orcus, Sedna, and ultimately Eris.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## David Rabinowitz - **Role in the video** - Also listed as a member of the Palomar team that carried out the TNO survey.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Contributions** - Co‑discoverer on the survey that produced multiple large TNO detections, including the object later named Eris.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Other credited contributors (production) These are production rather than scientific figures: - **Alex McColgan** – Narrator and “creator of Astrum,” presenting the story and explanations.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Jess Jordan** – Writer and “Head of Astrum.”[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Nick Shishkin** – Video editor.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Shourya Shrivastava** – Researcher.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Damaris McColgan** – Script editor.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Peter Sheppard** – Thumbnail designer.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Georgina Brenner, Raquel Taylor, Poppy Pinnock** – Publishing lead, production manager, and edit producer respectively.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Celestial objects mentioned and key facts ## Objects explicitly discussed as discoveries / focus From the transcript, the main outer‑solar‑system bodies highlighted as discoveries or comparison objects are: - Eris (2003 UB313) - Pluto - Dysnomia (moon of Eris) - Haumea - Makemake - Sedna - Quaoar - Orcus - Ceres[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ Below is a compact table using only values actually given or clearly implied in the video; blanks mean the specific number was not stated there. ## Selected properties of mentioned bodies (as stated in the video) |Body|Type in video|Size info (diameter / relative)|Mass / density info|Brightness / albedo info|Orbit / distance info|Discovery / designation info|Names / mythological origin (see next section)| |---|---|---|---|---|---|---|---| |**Eris**|Dwarf planet|Diameter 2,326 km, slightly smaller than Pluto [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|27% more massive than Pluto; density 2.43 g/cm³ [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Bond albedo ~0.99 (very bright) [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|557‑year period; perihelion ~38 AU, aphelion ~98 AU; 44° inclination [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Found in images from 21 Oct 2003; designated 2003 UB313; discovery announced 29 Jul 2005 [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Named after Eris, Greek goddess of strife and discord [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​| |**Pluto**|Dwarf planet (after 2006)|Size very similar; slightly larger than Eris [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Density 1.85 g/cm³, less dense than Eris [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Not specified numerically|Average orbit roughly comparable to Eris’s perihelion (~38 AU) [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Long‑known 9th planet; demoted by 2006 IAU vote [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Named after Pluto, Roman god of the underworld (alluded via status) [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​| |**Dysnomia**|Moon of Eris|~25% of Eris’s diameter; larger than Enceladus or Mimas [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Mass low enough that usual tidal‑locking expectations are not met; implies Eris dissipates energy easily [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Extremely dark, “darker than coal” [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Nearly circular 16‑day orbit; tidally locked to Eris [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Discovered Sept 2005 with Keck adaptive optics [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Named after Dysnomia, spirit of lawlessness, daughter of Eris [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​| |**Haumea**|Large TNO / dwarf planet candidate|Mentioned as a large TNO comparable in class to Eris [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Not quantified|Not specified|In outer solar system, beyond Neptune [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Announced by another team in July 2005 using Brown’s public logs [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Name not explained in‑video (Polynesian goddess in broader context)| |**Makemake**|Large TNO / dwarf planet candidate|Grouped with other large TNOs like Eris and Haumea [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Not quantified|Not specified|Trans‑Neptunian region beyond Neptune [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Discovery details not elaborated|Name not explained in‑video| |**Sedna**|Distant TNO|Listed as one of the large TNOs discovered by Brown’s team [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Not quantified|Not specified|Very distant, beyond Neptune (implied) [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Discovery previously by Brown’s team [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Name not explained in‑video| |**Quaoar**|TNO|Cited as one of the “newly discovered worlds” from the survey [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Not quantified|Not specified|Trans‑Neptunian region [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Survey discovery before Eris [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Name not explained in‑video| |**Orcus**|TNO|Another “newly discovered world” from survey [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Not quantified|Not specified|Trans‑Neptunian region [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Survey discovery before Eris [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Name not explained in‑video| |**Ceres**|Dwarf planet|Not sized numerically; noted as promoted from asteroid to dwarf planet [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Not quantified|Not specified|In asteroid belt between Mars and Jupiter (implied by context) [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Reclassified as dwarf planet in 2006 along with Pluto and Eris [youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​|Name not explained in‑video| Because the video does not supply specific numbers for many of these objects (e.g., Haumea’s size, Ceres’s diameter), the table only includes values directly mentioned.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Mythological origins of names (as described or implied) The video explicitly explains only the Eris–Dysnomia myth pair; other etymologies are mentioned only by name. - **Eris** - In Greek myth, Eris is the goddess of **strife**, excluded from a divine wedding and retaliating by throwing a golden apple labeled “For the fairest” among the goddesses, sparking a dispute that leads to the Trojan War.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - The video uses this to parallel how the discovery of Eris “threw” a disruptive problem into astronomy and triggered the IAU planet‑definition conflict.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Dysnomia** - Named after Eris’s mythological daughter, a daemon spirit of **lawlessness**.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - The video notes the name as fitting for a moon born from a chaotic giant impact and orbiting a world that overturned the “laws” of the solar system.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Pluto** - While not spelled out, Pluto is the Roman counterpart of the Greek underworld god Hades; the video leans on Pluto’s cultural status rather than retelling the myth.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Other bodies (Haumea, Makemake, Sedna, Quaoar, Orcus, Ceres)** - The video only mentions these names in passing and does not recount their mythological backstories; it focuses instead on their dynamical and classification relevance.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## The IAU “planet” motion and arguments ## Motion and formal criteria At the 26th IAU General Assembly (Prague, 2006), the union adopted Resolution 5A which, as summarized in the video, defined a planet in the solar system as a body that:[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ 1. **Orbits the Sun**. 2. **Is in hydrostatic equilibrium**, i.e., has sufficient mass for its self‑gravity to overcome material strength and assume a nearly round shape. 3. **Has “cleared the neighbourhood” around its orbit**, meaning it is the dominant gravitational body in its orbital region.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ Objects that meet only the first two criteria (orbit the Sun and are round) but have not cleared their orbits were placed into a new, separate category called **dwarf planets**.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ A second resolution, which would have made dwarf planets a **sub‑category of planets**, was brought forward but explicitly **defeated**, so the IAU declared planets and dwarf planets as distinct classes rather than dwarf planets being counted as planets.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Camps and core arguments The debate split participants into two main philosophical camps.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Geophysical definition camp** - Proposed that any body massive enough to reach hydrostatic equilibrium (nearly round) should be considered a planet, regardless of its orbital context.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Under this definition, Pluto, Eris, Ceres, and dozens of other round bodies in the outer solar system would all be planets.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Emphasis: intrinsic physical properties determine planethood. - **Dynamical definition camp** - Argued that a planet’s identity must include its **gravitational dominance**; it should be the main body in its orbital zone.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - This view led to the “cleared the neighbourhood” clause and to Pluto’s failure to qualify because it shares its region with many Kuiper Belt objects.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Emphasis: the role a body plays in structuring its region of the solar system. ## Process and controversy - The vote was held on the **last day** of a ten‑day meeting, when most attendees had already left; only 424 astronomers out of about 2,500 participants voted.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Critics highlighted:[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - The small voting pool. - The ambiguous nature of “cleared the neighbourhood.” - The parochial “orbits the Sun” requirement, which fails to cover the thousands of known exoplanets and thus is not a universal definition. - Nonetheless, Resolution 5A passed, immediately reducing the official count to eight planets and recasting Pluto, Eris, and Ceres as dwarf planets.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ If you want, the next step could be to build an Obsidian‑ready note structure from this: one note for the IAU debate, one for Eris/Dysnomia as a system, and one for each of the named TNOs with cross‑links by theme (dynamics, mythology, discovery history). 1. [https://www.youtube.com/watch?v=MHsDI83dZ_s](https://www.youtube.com/watch?v=MHsDI83dZ_s) ---- Here is an updated table with the “not quantified” entries filled from external sources. All values are approximate; ranges or representative values are chosen where multiple slightly different measurements exist.wikipedia+8​ ## Expanded properties of mentioned bodies |Body|Type (current)|Diameter (km)|Mass (kg)|Mean density (g/cm³)|Geometric/Bond albedo (approx.)|Semi‑major axis (AU)|Orbital period (yr)|Discovery date / designation| |---|---|---|---|---|---|---|---|---| |**Eris**|Dwarf planet|2,326 ± 12 [wikipedia](https://en.wikipedia.org/wiki/Eris_\(dwarf_planet\))​|1.66 × 10²² [wikipedia](https://en.wikipedia.org/wiki/Eris_\(dwarf_planet\))​|2.5 ± 0.04 [pmc.ncbi.nlm.nih](https://pmc.ncbi.nlm.nih.gov/articles/PMC10651115/)​|Geometric ≈ 0.96; Bond ≈ 0.7–0.99 wikipedia+1​|67.7 [schoolsobservatory](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs)​|558 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Images from 21 Oct 2003; announced 2005 as 2003 UB313 wikipedia+1​| |**Pluto**|Dwarf planet|2,376.6 ± 3.2 [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|1.303 × 10²² [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|1.853 [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|Geometric 0.49–0.66 [solarviews](https://solarviews.com/eng/pluto.htm)​|39.48 [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|248.0 [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|Discovered 18 Feb 1930 by Clyde Tombaugh [wikipedia](https://en.wikipedia.org/wiki/Pluto)​| |**Dysnomia**|Moon of Eris|615⁺⁶⁰₋₅₀ [wikipedia](https://en.wikipedia.org/wiki/Dysnomia_\(moon\))​|8 × 10¹⁹ (≈0.008 × 10²²) wikipedia+1​|~0.7 (very uncertain) [pmc.ncbi.nlm.nih](https://pmc.ncbi.nlm.nih.gov/articles/PMC10651115/)​|Geometric ≈ 0.05 [wikipedia](https://en.wikipedia.org/wiki/Dysnomia_\(moon\))​|0.00025 (around Eris; 37,300 km) [wikipedia](https://en.wikipedia.org/wiki/Dysnomia_\(moon\))​|0.043 (15.8 days) [wikipedia](https://en.wikipedia.org/wiki/Dysnomia_\(moon\))​|Discovered 10 Sep 2005 with Keck AO wikipedia+1​| |**Haumea**|Dwarf planet|1,632–1,740 (equivalent sphere) visualcapitalist+1​|4.0 × 10²¹ [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|1.9–2.0 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Geometric ≈ 0.51–0.75 (very bright, icy) [sciencedirect](https://www.sciencedirect.com/topics/earth-and-planetary-sciences/dwarf-planet)​|43.1 [schoolsobservatory](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs)​|285 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|Discovered 2004; designated 2003 EL61 wikipedia+1​| |**Makemake**|Dwarf planet|1,430 visualcapitalist+1​|3.1 × 10²¹ [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|1.7–1.8 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Geometric ≈ 0.77 visualcapitalist+1​|45.8 [schoolsobservatory](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs)​|305 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Discovered 31 Mar 2005; 2005 FY9 wikipedia+1​| |**Sedna**|Distant TNO|~995 visualcapitalist+1​|~4 × 10²¹ (order of magnitude) [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|~2.0 (estimated) wikipedia+1​|Geometric ≈ 0.32 visualcapitalist+1​|~506 (highly elliptical) [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|~11,400 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Discovered 14 Nov 2003; 2003 VB12 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​| |**Quaoar**|Large TNO|1,110 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|1.4 × 10²¹ visualcapitalist+1​|1.7–2.0 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|Geometric ≈ 0.11–0.20 visualcapitalist+1​|43.6 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|286 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Discovered 4 Jun 2002; 2002 LM60 visualcapitalist+1​| |**Orcus**|Large TNO|910–920 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|6.4 × 10²⁰ [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|1.5–1.6 wikipedia+1​|Geometric ≈ 0.23 wikipedia+1​|39.2 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|247 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|Discovered 17 Feb 2004; 90482 Orcus [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​| |**Ceres**|Dwarf planet|940–946 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|9.39 × 10²⁰ [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|2.16 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|Geometric ≈ 0.09 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|2.77 [schoolsobservatory](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs)​|4.60 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|Discovered 1 Jan 1801 by Giuseppe Piazzi rmg+1​| If you want, the next step can be a second table focused only on mythological name origins for these same bodies, to sit alongside this numeric one in your Obsidian notes. 1. [https://en.wikipedia.org/wiki/Eris_(dwarf_planet)](https://en.wikipedia.org/wiki/Eris_\(dwarf_planet\)) 2. [https://en.wikipedia.org/wiki/Dysnomia_(moon)](https://en.wikipedia.org/wiki/Dysnomia_\(moon\)) 3. [https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/) 4. [https://science.nasa.gov/dwarf-planets/eris/](https://science.nasa.gov/dwarf-planets/eris/) 5. [https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris) 6. [https://solarviews.com/eng/pluto.htm](https://solarviews.com/eng/pluto.htm) 7. [https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs) 8. [https://en.wikipedia.org/wiki/Pluto](https://en.wikipedia.org/wiki/Pluto) 9. [https://ssd.jpl.nasa.gov/planets/phys_par.html](https://ssd.jpl.nasa.gov/planets/phys_par.html) 10. [https://pmc.ncbi.nlm.nih.gov/articles/PMC10651115/](https://pmc.ncbi.nlm.nih.gov/articles/PMC10651115/) 11. [https://usuaris.tinet.cat/klunn/eris.html](https://usuaris.tinet.cat/klunn/eris.html) 12. [https://www.sciencedirect.com/topics/earth-and-planetary-sciences/dwarf-planet](https://www.sciencedirect.com/topics/earth-and-planetary-sciences/dwarf-planet) 13. [https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets) 14. [https://en.wikipedia.org/wiki/Dwarf_planet](https://en.wikipedia.org/wiki/Dwarf_planet) 15. [https://thesolarsystem.fandom.com/wiki/Dwarf_planet](https://thesolarsystem.fandom.com/wiki/Dwarf_planet) 16. [https://www.youtube.com/watch?v=MHsDI83dZ_s](https://www.youtube.com/watch?v=MHsDI83dZ_s) 17. [https://assets.science.nasa.gov/content/dam/science/missions/hubble/releases/2007/06/STScI-01EVSRQ7G3BR52R50A5AFG41M7.pdf](https://assets.science.nasa.gov/content/dam/science/missions/hubble/releases/2007/06/STScI-01EVSRQ7G3BR52R50A5AFG41M7.pdf) 18. [https://www.johnstonsarchive.net/astro/astmoons/am-136199.html](https://www.johnstonsarchive.net/astro/astmoons/am-136199.html) 19. [https://web.gps.caltech.edu/~mbrown/planetlila/](https://web.gps.caltech.edu/~mbrown/planetlila/) 20. [https://www.universetoday.com/articles/dysnomia](https://www.universetoday.com/articles/dysnomia) 21. [https://arxiv.org/pdf/1203.0524.pdf](https://arxiv.org/pdf/1203.0524.pdf) 22. [https://kids.kiddle.co/Dysnomia_(moon)](https://kids.kiddle.co/Dysnomia_\(moon\)) 23. [https://space.fandom.com/wiki/Eris](https://space.fandom.com/wiki/Eris) 24. [http://www.krysstal.com/solarsys_minorplanets.html](http://www.krysstal.com/solarsys_minorplanets.html) 25. [https://chview.nova.org/solcom/stars/ub313.htm](https://chview.nova.org/solcom/stars/ub313.htm) 26. [https://phys.org/news/2015-07-eris-moon-dysnomia.pdf](https://phys.org/news/2015-07-eris-moon-dysnomia.pdf) 27. [https://solarballs.fandom.com/wiki/Dwarf_Planets](https://solarballs.fandom.com/wiki/Dwarf_Planets) 28. [https://www.ebsco.com/research-starters/astronomy-and-astrophysics/eris-i-dysnomia](https://www.ebsco.com/research-starters/astronomy-and-astrophysics/eris-i-dysnomia) 29. [https://phys.org/news/2015-07-eris-moon-dysnomia.html](https://phys.org/news/2015-07-eris-moon-dysnomia.html) 30. [https://www.britannica.com/place/Pluto-dwarf-planet/The-atmosphere](https://www.britannica.com/place/Pluto-dwarf-planet/The-atmosphere) 31. [https://www.facebook.com/Theskycore/posts/-meet-the-dwarf-planets-of-our-solar-system-they-may-be-small-but-theyre-full-of/714328184818056/](https://www.facebook.com/Theskycore/posts/-meet-the-dwarf-planets-of-our-solar-system-they-may-be-small-but-theyre-full-of/714328184818056/) 32. [https://pluto.jhuapl.edu/Pluto/The-Pluto-System.php](https://pluto.jhuapl.edu/Pluto/The-Pluto-System.php) 33. [https://www2.boulder.swri.edu/~buie/biblio/pub097.pdf](https://www2.boulder.swri.edu/~buie/biblio/pub097.pdf) 34. [https://ntrs.nasa.gov/api/citations/20210012932/downloads/21-49.pdf](https://ntrs.nasa.gov/api/citations/20210012932/downloads/21-49.pdf) ----- # Additional Facts from External Sources Here is an updated table with the “not quantified” entries filled from external sources. All values are approximate; ranges or representative values are chosen where multiple slightly different measurements exist.wikipedia+8​ ## Expanded properties of mentioned bodies |Body|Type (current)|Diameter (km)|Mass (kg)|Mean density (g/cm³)|Geometric/Bond albedo (approx.)|Semi‑major axis (AU)|Orbital period (yr)|Discovery date / designation| |---|---|---|---|---|---|---|---|---| |**Eris**|Dwarf planet|2,326 ± 12 [wikipedia](https://en.wikipedia.org/wiki/Eris_\(dwarf_planet\))​|1.66 × 10²² [wikipedia](https://en.wikipedia.org/wiki/Eris_\(dwarf_planet\))​|2.5 ± 0.04 [pmc.ncbi.nlm.nih](https://pmc.ncbi.nlm.nih.gov/articles/PMC10651115/)​|Geometric ≈ 0.96; Bond ≈ 0.7–0.99 wikipedia+1​|67.7 [schoolsobservatory](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs)​|558 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Images from 21 Oct 2003; announced 2005 as 2003 UB313 wikipedia+1​| |**Pluto**|Dwarf planet|2,376.6 ± 3.2 [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|1.303 × 10²² [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|1.853 [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|Geometric 0.49–0.66 [solarviews](https://solarviews.com/eng/pluto.htm)​|39.48 [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|248.0 [wikipedia](https://en.wikipedia.org/wiki/Pluto)​|Discovered 18 Feb 1930 by Clyde Tombaugh [wikipedia](https://en.wikipedia.org/wiki/Pluto)​| |**Dysnomia**|Moon of Eris|615⁺⁶⁰₋₅₀ [wikipedia](https://en.wikipedia.org/wiki/Dysnomia_\(moon\))​|8 × 10¹⁹ (≈0.008 × 10²²) wikipedia+1​|~0.7 (very uncertain) [pmc.ncbi.nlm.nih](https://pmc.ncbi.nlm.nih.gov/articles/PMC10651115/)​|Geometric ≈ 0.05 [wikipedia](https://en.wikipedia.org/wiki/Dysnomia_\(moon\))​|0.00025 (around Eris; 37,300 km) [wikipedia](https://en.wikipedia.org/wiki/Dysnomia_\(moon\))​|0.043 (15.8 days) [wikipedia](https://en.wikipedia.org/wiki/Dysnomia_\(moon\))​|Discovered 10 Sep 2005 with Keck AO wikipedia+1​| |**Haumea**|Dwarf planet|1,632–1,740 (equivalent sphere) visualcapitalist+1​|4.0 × 10²¹ [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|1.9–2.0 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Geometric ≈ 0.51–0.75 (very bright, icy) [sciencedirect](https://www.sciencedirect.com/topics/earth-and-planetary-sciences/dwarf-planet)​|43.1 [schoolsobservatory](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs)​|285 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|Discovered 2004; designated 2003 EL61 wikipedia+1​| |**Makemake**|Dwarf planet|1,430 visualcapitalist+1​|3.1 × 10²¹ [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|1.7–1.8 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Geometric ≈ 0.77 visualcapitalist+1​|45.8 [schoolsobservatory](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs)​|305 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Discovered 31 Mar 2005; 2005 FY9 wikipedia+1​| |**Sedna**|Distant TNO|~995 visualcapitalist+1​|~4 × 10²¹ (order of magnitude) [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|~2.0 (estimated) wikipedia+1​|Geometric ≈ 0.32 visualcapitalist+1​|~506 (highly elliptical) [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|~11,400 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Discovered 14 Nov 2003; 2003 VB12 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​| |**Quaoar**|Large TNO|1,110 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|1.4 × 10²¹ visualcapitalist+1​|1.7–2.0 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|Geometric ≈ 0.11–0.20 visualcapitalist+1​|43.6 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|286 [visualcapitalist](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/)​|Discovered 4 Jun 2002; 2002 LM60 visualcapitalist+1​| |**Orcus**|Large TNO|910–920 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|6.4 × 10²⁰ [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|1.5–1.6 wikipedia+1​|Geometric ≈ 0.23 wikipedia+1​|39.2 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|247 [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​|Discovered 17 Feb 2004; 90482 Orcus [wikipedia](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets)​| |**Ceres**|Dwarf planet|940–946 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|9.39 × 10²⁰ [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|2.16 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|Geometric ≈ 0.09 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|2.77 [schoolsobservatory](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs)​|4.60 [rmg](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris)​|Discovered 1 Jan 1801 by Giuseppe Piazzi rmg+1​| If you want, the next step can be a second table focused only on mythological name origins for these same bodies, to sit alongside this numeric one in your Obsidian notes. 1. [https://en.wikipedia.org/wiki/Eris_(dwarf_planet)](https://en.wikipedia.org/wiki/Eris_\(dwarf_planet\)) 2. [https://en.wikipedia.org/wiki/Dysnomia_(moon)](https://en.wikipedia.org/wiki/Dysnomia_\(moon\)) 3. [https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/](https://www.visualcapitalist.com/a-visual-introduction-to-the-dwarf-planets-in-our-solar-system/) 4. [https://science.nasa.gov/dwarf-planets/eris/](https://science.nasa.gov/dwarf-planets/eris/) 5. [https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris](https://www.rmg.co.uk/stories/space-astronomy/dwarf-planets-pluto-ceres-haumea-makemake-eris) 6. [https://solarviews.com/eng/pluto.htm](https://solarviews.com/eng/pluto.htm) 7. [https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs](https://www.schoolsobservatory.org/learn/space/solar-system/dwarfs) 8. [https://en.wikipedia.org/wiki/Pluto](https://en.wikipedia.org/wiki/Pluto) 9. [https://ssd.jpl.nasa.gov/planets/phys_par.html](https://ssd.jpl.nasa.gov/planets/phys_par.html) 10. [https://pmc.ncbi.nlm.nih.gov/articles/PMC10651115/](https://pmc.ncbi.nlm.nih.gov/articles/PMC10651115/) 11. [https://usuaris.tinet.cat/klunn/eris.html](https://usuaris.tinet.cat/klunn/eris.html) 12. [https://www.sciencedirect.com/topics/earth-and-planetary-sciences/dwarf-planet](https://www.sciencedirect.com/topics/earth-and-planetary-sciences/dwarf-planet) 13. [https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets](https://en.wikipedia.org/wiki/List_of_possible_dwarf_planets) 14. [https://en.wikipedia.org/wiki/Dwarf_planet](https://en.wikipedia.org/wiki/Dwarf_planet) 15. [https://thesolarsystem.fandom.com/wiki/Dwarf_planet](https://thesolarsystem.fandom.com/wiki/Dwarf_planet) 16. [https://www.youtube.com/watch?v=MHsDI83dZ_s](https://www.youtube.com/watch?v=MHsDI83dZ_s) 17. [https://assets.science.nasa.gov/content/dam/science/missions/hubble/releases/2007/06/STScI-01EVSRQ7G3BR52R50A5AFG41M7.pdf](https://assets.science.nasa.gov/content/dam/science/missions/hubble/releases/2007/06/STScI-01EVSRQ7G3BR52R50A5AFG41M7.pdf) 18. [https://www.johnstonsarchive.net/astro/astmoons/am-136199.html](https://www.johnstonsarchive.net/astro/astmoons/am-136199.html) 19. [https://web.gps.caltech.edu/~mbrown/planetlila/](https://web.gps.caltech.edu/~mbrown/planetlila/) 20. [https://www.universetoday.com/articles/dysnomia](https://www.universetoday.com/articles/dysnomia) 21. [https://arxiv.org/pdf/1203.0524.pdf](https://arxiv.org/pdf/1203.0524.pdf) 22. [https://kids.kiddle.co/Dysnomia_(moon)](https://kids.kiddle.co/Dysnomia_\(moon\)) 23. [https://space.fandom.com/wiki/Eris](https://space.fandom.com/wiki/Eris) 24. [http://www.krysstal.com/solarsys_minorplanets.html](http://www.krysstal.com/solarsys_minorplanets.html) 25. [https://chview.nova.org/solcom/stars/ub313.htm](https://chview.nova.org/solcom/stars/ub313.htm) 26. [https://phys.org/news/2015-07-eris-moon-dysnomia.pdf](https://phys.org/news/2015-07-eris-moon-dysnomia.pdf) 27. [https://solarballs.fandom.com/wiki/Dwarf_Planets](https://solarballs.fandom.com/wiki/Dwarf_Planets) 28. [https://www.ebsco.com/research-starters/astronomy-and-astrophysics/eris-i-dysnomia](https://www.ebsco.com/research-starters/astronomy-and-astrophysics/eris-i-dysnomia) 29. [https://phys.org/news/2015-07-eris-moon-dysnomia.html](https://phys.org/news/2015-07-eris-moon-dysnomia.html) 30. [https://www.britannica.com/place/Pluto-dwarf-planet/The-atmosphere](https://www.britannica.com/place/Pluto-dwarf-planet/The-atmosphere) 31. [https://www.facebook.com/Theskycore/posts/-meet-the-dwarf-planets-of-our-solar-system-they-may-be-small-but-theyre-full-of/714328184818056/](https://www.facebook.com/Theskycore/posts/-meet-the-dwarf-planets-of-our-solar-system-they-may-be-small-but-theyre-full-of/714328184818056/) 32. [https://pluto.jhuapl.edu/Pluto/The-Pluto-System.php](https://pluto.jhuapl.edu/Pluto/The-Pluto-System.php) 33. [https://www2.boulder.swri.edu/~buie/biblio/pub097.pdf](https://www2.boulder.swri.edu/~buie/biblio/pub097.pdf) 34. [https://ntrs.nasa.gov/api/citations/20210012932/downloads/21-49.pdf](https://ntrs.nasa.gov/api/citations/20210012932/downloads/21-49.pdf) ----- # Mythology Here is a myth‑focused table for the same bodies, kept concise but Obsidian‑ready. ## Mythological origins of names |Body|Mythic tradition|Figure / meaning|Key story points and associations| |---|---|---|---| |**Eris**|Greek|Goddess **Eris** (Ἔρις), personification of strife and discord wikipedia+2​|Not invited to the wedding of Peleus and Thetis; in revenge, throws a golden apple inscribed “For the fairest” among the goddesses Hera, Athena, and Aphrodite, sparking the Judgement of Paris and ultimately the Trojan War. Symbolizes chaos, rivalry, and conflict. wikipedia+2​| |**Pluto**|Roman (with Greek roots)|God **Pluto** (from Greek _Plouton_), ruler of the underworld and wealth romanmythology+2​|Roman counterpart of Hades; son of Saturn (Cronus) and Ops (Rhea), brother of Jupiter and Neptune. Abducts Proserpina (Persephone), whose periodic return to the surface explains the seasons. Governs the realm of the dead and subterranean riches, hence associated with both death and hidden wealth. historycooperative+2​| |**Dysnomia**|Greek|Spirit **Dysnomia** (“Lawlessness”), daughter of Eris kids.kiddle+1​|Personification of lawlessness or disregard for order; grouped among the troublesome offspring of Eris who embody social and moral disorder. Chosen to echo Eris’s disruptive character and to symbolize “breaking the rules” (fitting the moon of the body that forced a redefinition of planets). kids.kiddle+1​| |**Haumea**|Hawaiian|Goddess **Haumea**, deity of childbirth, fertility, and the earth universetoday+3​|Matron goddess of the island of Hawaiʻi, associated with fertility, childbirth, and the generative power of the land. Often identified with Papa, earth‑goddess and consort of Wākea (sky/space), representing the union of earth and heavens. Name chosen to honor Mauna Kea observatories and to match IAU guidance that classical Kuiper Belt objects use creation‑associated deities. universetoday+2​| |**Makemake**|Rapa Nui (Easter Island)|Creator god **Makemake**, chief deity of Rapa Nui religion [theplanets](https://theplanets.org/dwarf-planets/)​|Associated with creation, fertility, and the bird‑man cult on Rapa Nui; revered as a powerful creator and bringer of abundance. Selected to follow the convention of naming outer objects after creation‑linked deities, extending representation beyond Greco‑Roman traditions. [theplanets](https://theplanets.org/dwarf-planets/)​| |**Sedna**|Inuit (Arctic)|Goddess **Sedna**, ruler of the sea and marine animals [theplanets](https://theplanets.org/dwarf-planets/)​|Young woman who, in various versions, is cast into the sea by her father; her severed fingers become seals, whales, and other sea creatures. Dwells at the bottom of the ocean, controlling marine life and requiring shamans to appease her when game is scarce. Often invoked to explain both bounty and famine in the Arctic seas. [theplanets](https://theplanets.org/dwarf-planets/)​| |**Quaoar**|Tongva (Native Californian)|Deity **Quaoar**, creator god of the Tongva people of the Los Angeles Basin [theplanets](https://theplanets.org/dwarf-planets/)​|A primeval being who dances and sings the world into existence, bringing forth other deities and, through them, shaping the cosmos. Name acknowledges the indigenous people of the region where the discovering observatory stands and follows the pattern of using creation‑linked mythic figures. [theplanets](https://theplanets.org/dwarf-planets/)​| |**Orcus**|Roman / Italic|Chthonic god **Orcus**, punisher of oath‑breakers in the underworld theplanets+1​|Early Roman/Italic underworld deity associated with punishment of perjurers and breakers of oaths; later conflated with Pluto and Dis Pater. Represents the grim, punitive aspect of the afterlife rather than its wealth‑giving side. The name mirrors Pluto’s underworld theme and Orcus’s role as enforcer of divine law. theplanets+1​| |**Ceres**|Roman|Goddess **Ceres**, deity of agriculture, grain, and motherly nurture [theplanets](https://theplanets.org/dwarf-planets/)​|Roman counterpart of Greek Demeter; goddess of crops, especially grain, and of fertility of the fields. Central myth involves the abduction of her daughter Proserpina by Pluto; Ceres’ grief withers the earth until her daughter’s partial return, establishing the seasonal cycle. Name reflects Ceres’s link to cultivated land and food supply, fitting the largest object in the asteroid belt between Mars and Jupiter. theplanets+1​| If you want, a next pass can turn this into a set of atomic notes (one per body) with internal links like `[[Myth:Eris]]`, `[[Myth:Pluto]]`, etc., plus separate notes for “Underworld deities,” “Creation deities,” and “Law/chaos figures.” 1. [https://en.wikipedia.org/wiki/Eris_(mythology)](https://en.wikipedia.org/wiki/Eris_\(mythology\)) 2. [https://www.theoi.com/Daimon/Eris.html](https://www.theoi.com/Daimon/Eris.html) 3. [https://mythopedia.com/topics/eris/](https://mythopedia.com/topics/eris/) 4. [https://greekmythologytours.com/blog/greek-mythology/eris-goddess-chaos-strife](https://greekmythologytours.com/blog/greek-mythology/eris-goddess-chaos-strife) 5. [https://www.romanmythology.com/gods-goddesses/pluto/](https://www.romanmythology.com/gods-goddesses/pluto/) 6. [https://historycooperative.org/pluto-god/](https://historycooperative.org/pluto-god/) 7. [https://mythopedia.com/topics/pluto](https://mythopedia.com/topics/pluto) 8. [https://study.com/academy/lesson/roman-god-pluto-of-the-underworld-facts-lesson-quiz.html](https://study.com/academy/lesson/roman-god-pluto-of-the-underworld-facts-lesson-quiz.html) 9. [https://kids.kiddle.co/Dysnomia](https://kids.kiddle.co/Dysnomia) 10. [https://masksoferis.wordpress.com/2008/04/03/of-the-children-of-eris-discordia/](https://masksoferis.wordpress.com/2008/04/03/of-the-children-of-eris-discordia/) 11. [https://www.universetoday.com/articles/the-dwarf-planet-haumea](https://www.universetoday.com/articles/the-dwarf-planet-haumea) 12. [https://www.lovebigisland.com/hawaii-blog/haumea/](https://www.lovebigisland.com/hawaii-blog/haumea/) 13. [https://en.wikipedia.org/wiki/Haumea](https://en.wikipedia.org/wiki/Haumea) 14. [https://usuaris.tinet.cat/klunn/haumea.html](https://usuaris.tinet.cat/klunn/haumea.html) 15. [https://theplanets.org/dwarf-planets/](https://theplanets.org/dwarf-planets/) 16. [https://www.youtube.com/watch?v=MHsDI83dZ_s](https://www.youtube.com/watch?v=MHsDI83dZ_s) 17. [https://study.com/academy/lesson/eris-greek-goddess-strife-mythology-history.html](https://study.com/academy/lesson/eris-greek-goddess-strife-mythology-history.html) 18. [https://whispygypsy.com/pages/pluto](https://whispygypsy.com/pages/pluto) 19. [https://www.facebook.com/anetteprs/posts/eris-goddess-of-discord-chaos-and-strife-her-most-famous-appearance-in-mythology/499634362207032/](https://www.facebook.com/anetteprs/posts/eris-goddess-of-discord-chaos-and-strife-her-most-famous-appearance-in-mythology/499634362207032/) 20. [https://villains.fandom.com/wiki/Eris_(mythology)](https://villains.fandom.com/wiki/Eris_\(mythology\)) 21. [https://www.facebook.com/groups/leonardoaigroup/posts/2377462645972878/](https://www.facebook.com/groups/leonardoaigroup/posts/2377462645972878/) ----- # Discoveries and Methods The video describes a toolkit of discovery methods: wide‑field imaging plus blink/comparison for motion, orbit‑fitting from repeated astrometry, stellar occultations for size/shape, and satellite‑orbit analysis for mass and density, with spectroscopy and brightness giving surface/atmosphere clues.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Methods of discovery in the video - **Systematic wide‑field imaging + software search** - The Palomar team used the 1.2 m Samuel Oschin telescope to take repeated wide‑field images of the sky and ran them through automated software that flagged objects moving at certain speeds against background stars, revealing TNOs like Quaoar, Orcus, and Sedna.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Eris (then 2003 UB313) appears as a faint dot slowly shifting across three images from 21 October 2003; its very slow, but real, motion implied great distance.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Manual re‑examination of archival data** - After software missed some slow movers, Mike Brown manually re‑checked old data sets, stepping through multi‑image sequences to find subtle motion that automated filters had discarded.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - This manual blink‑comparison is how the team actually spotted Eris’s motion in the 2003 images.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Follow‑up tracking for orbit and classification** - Once Eris was identified, the team took further images over time to track its position, allowing orbital elements to be refined (distance, period, inclination, perihelion/aphelion).[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Similar wide‑field surveys and follow‑up observations led to identification of other large TNOs like Haumea, Makemake, and Sedna.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## How the size of a new body is determined - **Brightness + distance (rough initial estimate)** - Immediately after discovery, Eris’s size was only estimated: its brightness suggested it was either very large or very reflective, with the ambiguity depending on unknown albedo.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - These brightness‑based estimates are imprecise because a small, very reflective object can mimic the light of a larger, darker one.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Stellar occultation (precise measurement)** - In 2010 Eris passed in front of a distant star; by timing how long the star’s light was blocked from multiple locations, astronomers reconstructed Eris’s silhouette and determined its diameter (2,326 km) with high precision.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - The video emphasizes that this occultation overturned the earlier assumption that Eris was significantly larger than Pluto, showing it is instead almost the same size and in fact slightly smaller.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## How the paths (orbits) are determined - **Astrometric tracking over time** - After first detection, Eris was repeatedly imaged to record its position relative to background stars; these measurements feed into orbital solutions using celestial mechanics.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - The resulting fit gives a highly elongated 557‑year orbit, with perihelion ~38 AU, aphelion ~98 AU, and an inclination of 44° to the ecliptic, placing Eris in the scattered disc rather than the main Kuiper Belt.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Use of Kepler’s laws for satellites and orbits** - For the Eris–Dysnomia system, tracking Dysnomia’s nearly circular 16‑day orbit provides the gravitational parameter of the system; combining period and orbital radius via Kepler’s third law yields Eris’s mass.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - This same approach—observing a body’s gravitational effect on a moon or companion—is highlighted as the clean way to get mass, which then informs density and internal composition.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ ## Other discoveries and their methods - **Dysnomia (moon of Eris)** - Discovered in 2005 with the W. M. Keck telescope’s adaptive optics system, which corrects for atmospheric blurring to reach near space‑telescope resolution; in these sharpened images, a faint companion to Eris became visible.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Continued high‑resolution imaging allowed measurement of Dysnomia’s orbit, establishing its 16‑day period, approximate distance from Eris, and tidal locking, which in turn enabled the precise mass estimate for Eris.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Surface and atmosphere properties of Eris** - The extremely high albedo (∼0.99) is inferred from its brightness compared to its known size, indicating a very reflective surface coated in fresh frost.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - The video explains an “atmospheric collapse” cycle, deduced from Eris’s eccentric orbit and comparisons to Pluto: nitrogen–methane atmosphere sublimates near perihelion and freezes out as bright frost at aphelion.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Interior / possible geothermal activity** - The James Webb Space Telescope’s spectroscopy of methane isotopes on Eris’s surface suggests some methane may originate from internal processes, hinting at geothermal activity in the rocky core.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Combining this with the high density (from the Eris–Dysnomia mass) leads to the interpretation of a rock‑dominated interior with a thinner ice shell.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - **Population structure of the outer solar system** - Surveys like the Palomar program, plus many similar campaigns, reveal a “third realm” of thousands of icy bodies beyond Neptune, leading to the concept of the Kuiper Belt and scattered disc as distinct dynamical populations.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ - Eris and Pluto are portrayed as the largest, “king” members of this trans‑Neptunian population, discovered through the same imaging, tracking, and orbit‑fitting methods described above.[youtube](https://www.youtube.com/watch?v=MHsDI83dZ_s)​ If you like, the next step could be a short Obsidian note template that separates these methods into properties (discovery, size, orbit, interior) with fields you can fill for any future outer‑solar‑system object. 1. [https://www.youtube.com/watch?v=MHsDI83dZ_s](https://www.youtube.com/watch?v=MHsDI83dZ_s) -----