IC418
E540379
IC 418 is a small, bright planetary nebula in the constellation Lepus, often called the Spirograph Nebula for its intricate, filamentary appearance.
All labels observed (1)
| Label | Occurrences |
|---|---|
| IC418 canonical | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T5723722 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: IC418 Context triple: [Lepus, containsDeepSkyObject, IC418]
-
A.
IC 4895
IC 4895 is a barred irregular dwarf galaxy in the Local Group, better known as NGC 6822 or Barnard's Galaxy, located in the constellation Sagittarius.
-
B.
IC 1848
IC 1848, also known as the Soul Nebula, is a large emission nebula and star-forming region in the constellation Cassiopeia, often paired with the nearby Heart Nebula (IC 1805).
-
C.
IC 4665
IC 4665 is a bright, young open star cluster located in the constellation Ophiuchus, visible with binoculars or small telescopes.
-
D.
IC 1805
IC 1805 is a large emission nebula and active star-forming region in the constellation Cassiopeia, notable for its heart-shaped appearance and young, massive star cluster.
-
E.
IC 4715
IC 4715 is a bright, star-rich region of the Milky Way in the constellation Sagittarius, commonly known as the Small Sagittarius Star Cloud.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: IC418 Target entity description: IC 418 is a small, bright planetary nebula in the constellation Lepus, often called the Spirograph Nebula for its intricate, filamentary appearance.
-
A.
IC 4895
IC 4895 is a barred irregular dwarf galaxy in the Local Group, better known as NGC 6822 or Barnard's Galaxy, located in the constellation Sagittarius.
-
B.
IC 1848
IC 1848, also known as the Soul Nebula, is a large emission nebula and star-forming region in the constellation Cassiopeia, often paired with the nearby Heart Nebula (IC 1805).
-
C.
IC 4665
IC 4665 is a bright, young open star cluster located in the constellation Ophiuchus, visible with binoculars or small telescopes.
-
D.
IC 1805
IC 1805 is a large emission nebula and active star-forming region in the constellation Cassiopeia, notable for its heart-shaped appearance and young, massive star cluster.
-
E.
IC 4715
IC 4715 is a bright, star-rich region of the Milky Way in the constellation Sagittarius, commonly known as the Small Sagittarius Star Cloud.
- F. None of above. chosen
Statements (44)
| Predicate | Object |
|---|---|
| instanceOf |
emission nebula
ⓘ
planetary nebula ⓘ |
| alternativeName | Spirograph Nebula ⓘ |
| angularDiameter | ~12 arcseconds ⓘ |
| apparentMagnitudeV | ~9.6 ⓘ |
| bestSeenIn | small to medium amateur telescopes ⓘ |
| catalog | Index Catalogue ⓘ |
| catalogNumber | IC 418 ⓘ |
| centralStarEffectiveTemperature | ~39,000 K ⓘ |
| centralStarType | hot white dwarf ⓘ |
| declination | -12° 42′ (approx) ⓘ |
| discoveredBy | Williamina Fleming ⓘ |
| discoveryYear | 1891 ⓘ |
| distanceFromEarth |
~1.1 kiloparsecs
ⓘ
~3600 light-years ⓘ |
| dominantEmissionLines |
H-alpha
ⓘ
[N II] ⓘ [O III] ⓘ |
| evolutionaryStage | late stage of low- to intermediate-mass star ⓘ |
| excitationClass | high-excitation nebula ⓘ |
| expandingGas | ionized gas shell ⓘ |
| formationMechanism | ejected outer layers of dying star ⓘ |
| hasCentralStarMagnitude | ~10.2 ⓘ |
| hasColor | reddish and greenish hues in images ⓘ |
| hasStructure |
fainter outer halo
ⓘ
inner bright shell ⓘ |
| imageNicknameOrigin | Spirograph-like pattern in HST images ⓘ |
| ionizationSource | ultraviolet radiation from central star ⓘ |
| locatedInConstellation | Lepus ⓘ |
| locatedInGalaxy | Milky Way ⓘ |
| morphologicalType | elliptical planetary nebula ⓘ |
| notableFor |
high surface brightness
ⓘ
intricate filamentary structure ⓘ ring-like inner shell ⓘ |
| observedBy | Hubble Space Telescope ⓘ |
| observedIn |
infrared wavelengths
ⓘ
optical wavelengths ⓘ radio wavelengths ⓘ |
| rightAscension | 05h 27m (approx) ⓘ |
| shapeDescription | nearly circular on the sky ⓘ |
| spectralFeatures |
recombination lines of hydrogen and helium
ⓘ
strong forbidden lines ⓘ |
| surfaceBrightness | high ⓘ |
| visibleFromHemisphere | Southern Hemisphere ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: IC418 Description of subject: IC 418 is a small, bright planetary nebula in the constellation Lepus, often called the Spirograph Nebula for its intricate, filamentary appearance.
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.