{"openapi":"3.1.0","info":{"title":"Star Catalog","version":"1.0.0","description":"Look up bright and nearby stars, cone searches, constellations, distances, luminosity and visibility by latitude. One call, one computed answer, no accounts or API keys. Machine-payable over x402.","x-guidance":"Star Catalog: Look up bright and nearby stars, cone searches, constellations, distances, luminosity and visibility by latitude. Use /star-lookup for a star by name, Bayer, Flamsteed, HR, HIP, HD or Gliese number, /brightest-stars for a ranking overall or by constellation, /stars-near-sky-point for a cone search around RA and Dec, /stars-in-constellation to list a constellation, /constellation-info for the 88 IAU constellations, /star-distance-and-luminosity for absolute magnitude and luminosity from apparent magnitude and parallax, /nearest-stars for the closest stars, and /star-visibility-from-latitude for whether a star rises from a latitude and its maximum altitude. Each paid GET returns a computed verdict with the reasons, the source and what was NOT checked. A verdict of UNVERIFIED means a lookup failed: treat it as unknown. No account or key: pay per call in USDC over x402."},"servers":[{"url":"https://star-catalog.x402tookit.com"}],"paths":{"/brightest-stars":{"get":{"operationId":"brightest_stars","summary":"The N brightest stars by apparent magnitude in the whole sky or in one constellation (name or IAU code).","description":"The N brightest stars by apparent magnitude in the whole sky or in one constellation (name or IAU code).","tags":["stars","astronomy","magnitude","ranking"],"parameters":[{"name":"n","in":"query","required":false,"description":"How many, 1 to 100 (default 10)","schema":{"type":"integer"}},{"name":"constellation","in":"query","required":false,"description":"Optional: Orion, Ori, Canis Major","schema":{"type":"string"}}],"responses":{"200":{"description":"The answer.","content":{"application/json":{"schema":{"type":"object","properties":{"verdict":{"type":["null","string"]},"summary":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"constellation":{},"stars":{"type":["array","null"],"items":{"type":"object","properties":{"rank":{"type":["null","number"]},"name":{"type":["null","string"]},"designations":{"type":["null","object"],"properties":{"proper":{"type":["null","string"]},"bayer":{"type":["null","string"]},"flamsteed":{"type":["null","string"]},"hr":{"type":["null","number"]},"hip":{"type":["null","number"]},"hd":{"type":["null","number"]},"gliese":{"type":["null","string"]}}},"constellation":{"type":["null","string"]},"constellationAbbr":{"type":["null","string"]},"apparentMagnitude":{"type":["null","number"]},"spectralType":{"type":["null","string"]},"colorIndexBV":{"type":["null","number"]},"raDeg":{"type":["null","number"]},"raHours":{"type":["null","number"]},"decDeg":{"type":["null","number"]},"epoch":{"type":["null","string"]},"parallaxMas":{"type":["null","number"]},"distanceParsecs":{"type":["null","number"]},"distanceLightYears":{"type":["null","number"]},"absoluteMagnitude":{"type":["null","number"]},"luminositySolar":{"type":["null","number"]},"properMotionRaMasPerYr":{"type":["null","number"]},"properMotionDecMasPerYr":{"type":["null","number"]},"radialVelocityKmS":{"type":["null","number"]}}}},"attribution":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"source":{"type":["null","string"]},"asOf":{"type":["null","string"]},"disclaimer":{"type":["null","string"]}}},"example":{"verdict":"RANKED","summary":"Brightest: Sirius (-1.44), Canopus (-0.62), Arcturus (-0.05).","reasons":["Lower magnitude means brighter."],"constellation":null,"stars":[{"rank":1,"name":"Sirius","designations":{"proper":"Sirius","bayer":"Alpha Canis Majoris","flamsteed":"9 Canis Majoris","hr":2491,"hip":32349,"hd":48915,"gliese":"Gl 244A"},"constellation":"Canis Major","constellationAbbr":"CMa","apparentMagnitude":-1.44,"spectralType":"A0m...","colorIndexBV":0.009,"raDeg":101.28722,"raHours":6.75248,"decDeg":-16.71612,"epoch":"J2000.0","parallaxMas":379.2,"distanceParsecs":2.6371,"distanceLightYears":8.6,"absoluteMagnitude":1.454,"luminositySolar":22.824,"properMotionRaMasPerYr":-546.01,"properMotionDecMasPerYr":-1223.08,"radialVelocityKmS":-9.4},{"rank":2,"name":"Canopus","designations":{"proper":"Canopus","bayer":"Alpha Carinae","flamsteed":null,"hr":2326,"hip":30438,"hd":45348,"gliese":null},"constellation":"Carina","constellationAbbr":"Car","apparentMagnitude":-0.62,"spectralType":"F0Ib","colorIndexBV":0.164,"raDeg":95.98792,"raHours":6.39919,"decDeg":-52.69566,"epoch":"J2000.0","parallaxMas":10.55,"distanceParsecs":94.7867,"distanceLightYears":309.15,"absoluteMagnitude":-5.504,"luminositySolar":13854.792,"properMotionRaMasPerYr":19.99,"properMotionDecMasPerYr":23.67,"radialVelocityKmS":21}],"attribution":"Star data: HYG database v4.1 by David Nash (astronexus), CC BY-SA 4.0; bright (V<=6.5) and nearest-200 subset, built 2026-10-21.","degraded":false,"notChecked":["stars fainter than magnitude 6.5","variable stars at their current brightness (the catalogue value is one mean or maximum value)","…1 more"],"source":"HYG database v4.1 (CC BY-SA 4.0: Hipparcos, Yale Bright Star, Gliese), computed locally","asOf":"2026-10-21T05:44:16.362Z","disclaimer":"Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting."}}}},"400":{"description":"A parameter was missing or out of range."},"402":{"description":"Payment Required"},"502":{"description":"The upstream source failed or timed out."}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.0200"},"protocols":[{"x402":{"network":"eip155:8453","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/brightest-stars"}},{"x402":{"network":"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/brightest-stars"}},{"x402":{"network":"eip155:137","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/brightest-stars"}},{"x402":{"network":"eip155:42161","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/brightest-stars"}}]}}},"/constellation-info":{"get":{"operationId":"constellation_info","summary":"IAU constellation facts: 3-letter code, genitive, bright stars; pass 'list' for all 88 constellations.","description":"IAU constellation facts: 3-letter code, genitive, bright stars; pass 'list' for all 88 constellations.","tags":["constellations","iau","astronomy","reference"],"parameters":[{"name":"q","in":"query","required":true,"description":"Name, genitive or code (Canis Major, Canis Majoris, CMa), or 'list'","schema":{"type":"string"}}],"responses":{"200":{"description":"The answer.","content":{"application/json":{"schema":{"type":"object","properties":{"verdict":{"type":["null","string"]},"summary":{"type":["null","string"]},"reasons":{"type":["array","null"]},"abbr":{"type":["null","string"]},"name":{"type":["null","string"]},"genitive":{"type":["null","string"]},"catalogedStarCount":{"type":["null","number"]},"brightStars":{"type":["array","null"],"items":{"type":"object","properties":{"name":{"type":["null","string"]},"designations":{"type":["null","object"],"properties":{"proper":{"type":["null","string"]},"bayer":{"type":["null","string"]},"flamsteed":{"type":["null","string"]},"hr":{"type":["null","number"]},"hip":{"type":["null","number"]},"hd":{"type":["null","number"]},"gliese":{"type":["null","string"]}}},"constellation":{"type":["null","string"]},"constellationAbbr":{"type":["null","string"]},"apparentMagnitude":{"type":["null","number"]},"spectralType":{"type":["null","string"]},"colorIndexBV":{"type":["null","number"]},"raDeg":{"type":["null","number"]},"raHours":{"type":["null","number"]},"decDeg":{"type":["null","number"]},"epoch":{"type":["null","string"]},"parallaxMas":{"type":["null","number"]},"distanceParsecs":{"type":["null","number"]},"distanceLightYears":{"type":["null","number"]},"absoluteMagnitude":{"type":["null","number"]},"luminositySolar":{"type":["null","number"]},"properMotionRaMasPerYr":{"type":["null","number"]},"properMotionDecMasPerYr":{"type":["null","number"]},"radialVelocityKmS":{"type":["null","number"]}}}},"attribution":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"source":{"type":["null","string"]},"asOf":{"type":["null","string"]},"disclaimer":{"type":["null","string"]}}},"example":{"verdict":"FOUND","summary":"Canis Major (CMa), genitive Canis Majoris; 149 catalogued stars, brightest Sirius.","reasons":[],"abbr":"CMa","name":"Canis Major","genitive":"Canis Majoris","catalogedStarCount":149,"brightStars":[{"name":"Sirius","designations":{"proper":"Sirius","bayer":"Alpha Canis Majoris","flamsteed":"9 Canis Majoris","hr":2491,"hip":32349,"hd":48915,"gliese":"Gl 244A"},"constellation":"Canis Major","constellationAbbr":"CMa","apparentMagnitude":-1.44,"spectralType":"A0m...","colorIndexBV":0.009,"raDeg":101.28722,"raHours":6.75248,"decDeg":-16.71612,"epoch":"J2000.0","parallaxMas":379.2,"distanceParsecs":2.6371,"distanceLightYears":8.6,"absoluteMagnitude":1.454,"luminositySolar":22.824,"properMotionRaMasPerYr":-546.01,"properMotionDecMasPerYr":-1223.08,"radialVelocityKmS":-9.4},{"name":"Adhara","designations":{"proper":"Adhara","bayer":"Epsilon Canis Majoris","flamsteed":"21 Canis Majoris","hr":2618,"hip":33579,"hd":52089,"gliese":null},"constellation":"Canis Major","constellationAbbr":"CMa","apparentMagnitude":1.5,"spectralType":"B2II","colorIndexBV":-0.211,"raDeg":104.65646,"raHours":6.9771,"decDeg":-28.97208,"epoch":"J2000.0","parallaxMas":8.05,"distanceParsecs":124.2236,"distanceLightYears":405.16,"absoluteMagnitude":-3.971,"luminositySolar":3375.981,"properMotionRaMasPerYr":2.63,"properMotionDecMasPerYr":2.29,"radialVelocityKmS":27}],"attribution":"Star data: HYG database v4.1 by David Nash (astronexus), CC BY-SA 4.0; bright (V<=6.5) and nearest-200 subset, built 2026-10-21.","degraded":false,"notChecked":["constellation boundaries and areas (not in the data)","asterisms, which are not constellations","…1 more"],"source":"HYG database v4.1 (CC BY-SA 4.0: Hipparcos, Yale Bright Star, Gliese), computed locally","asOf":"2026-10-21T05:44:16.614Z","disclaimer":"Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting."}}}},"400":{"description":"A parameter was missing or out of range."},"402":{"description":"Payment Required"},"502":{"description":"The upstream source failed or timed out."}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.0200"},"protocols":[{"x402":{"network":"eip155:8453","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/constellation-info"}},{"x402":{"network":"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/constellation-info"}},{"x402":{"network":"eip155:137","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/constellation-info"}},{"x402":{"network":"eip155:42161","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/constellation-info"}}]}}},"/nearest-stars":{"get":{"operationId":"nearest_stars","summary":"The N closest stars to the Sun (max 200) with distance in light years, parallax, magnitude and spectral type.","description":"The N closest stars to the Sun (max 200) with distance in light years, parallax, magnitude and spectral type.","tags":["stars","astronomy","nearby","distance"],"parameters":[{"name":"n","in":"query","required":false,"description":"How many, 1 to 200 (default 10)","schema":{"type":"integer"}}],"responses":{"200":{"description":"The answer.","content":{"application/json":{"schema":{"type":"object","properties":{"verdict":{"type":["null","string"]},"summary":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"stars":{"type":["array","null"],"items":{"type":"object","properties":{"rank":{"type":["null","number"]},"name":{"type":["null","string"]},"designations":{"type":["null","object"],"properties":{"proper":{"type":["null","string"]},"bayer":{"type":["null","string"]},"flamsteed":{},"hr":{"type":["null","number"]},"hip":{"type":["null","number"]},"hd":{"type":["null","number"]},"gliese":{"type":["null","string"]}}},"constellation":{"type":["null","string"]},"constellationAbbr":{"type":["null","string"]},"apparentMagnitude":{"type":["null","number"]},"spectralType":{"type":["null","string"]},"colorIndexBV":{"type":["null","number"]},"raDeg":{"type":["null","number"]},"raHours":{"type":["null","number"]},"decDeg":{"type":["null","number"]},"epoch":{"type":["null","string"]},"parallaxMas":{"type":["null","number"]},"distanceParsecs":{"type":["null","number"]},"distanceLightYears":{"type":["null","number"]},"absoluteMagnitude":{"type":["null","number"]},"luminositySolar":{"type":["null","number"]},"properMotionRaMasPerYr":{"type":["null","number"]},"properMotionDecMasPerYr":{"type":["null","number"]},"radialVelocityKmS":{"type":["null","number"]}}}},"attribution":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"source":{"type":["null","string"]},"asOf":{"type":["null","string"]},"disclaimer":{"type":["null","string"]}}},"example":{"verdict":"RANKED","summary":"Nearest: Proxima Centauri 4.23 ly, Toliman 4.32 ly, Rigil Kentaurus 4.32 ly.","reasons":["Distances are 1000 / parallax in mas, converted at 3.26156 ly per parsec."],"stars":[{"rank":1,"name":"Proxima Centauri","designations":{"proper":"Proxima Centauri","bayer":null,"flamsteed":null,"hr":null,"hip":70890,"hd":null,"gliese":"Gl 551"},"constellation":"Centaurus","constellationAbbr":"Cen","apparentMagnitude":11.01,"spectralType":"M5Ve","colorIndexBV":1.807,"raDeg":217.43978,"raHours":14.49599,"decDeg":-62.67948,"epoch":"J2000.0","parallaxMas":771.66,"distanceParsecs":1.2959,"distanceLightYears":4.23,"absoluteMagnitude":15.447,"luminositySolar":0,"properMotionRaMasPerYr":-3775.64,"properMotionDecMasPerYr":768.16,"radialVelocityKmS":-16},{"rank":2,"name":"Toliman","designations":{"proper":"Toliman","bayer":"Alpha-2 Centauri","flamsteed":null,"hr":5460,"hip":71681,"hd":128621,"gliese":"Gl 559B"},"constellation":"Centaurus","constellationAbbr":"Cen","apparentMagnitude":1.35,"spectralType":"K1V","colorIndexBV":0.9,"raDeg":219.90519,"raHours":14.66035,"decDeg":-60.8383,"epoch":"J2000.0","parallaxMas":754.83,"distanceParsecs":1.3248,"distanceLightYears":4.32,"absoluteMagnitude":5.739,"luminositySolar":0.441,"properMotionRaMasPerYr":-3678.19,"properMotionDecMasPerYr":481.84,"radialVelocityKmS":-26.2}],"attribution":"Star data: HYG database v4.1 by David Nash (astronexus), CC BY-SA 4.0; bright (V<=6.5) and nearest-200 subset, built 2026-10-21.","degraded":false,"notChecked":["brown dwarfs and very faint stars that the catalogue lacks, and recent discoveries","that components of one system (Alpha Centauri A, B, Proxima) are listed separately","…1 more"],"source":"HYG database v4.1 (CC BY-SA 4.0: Hipparcos, Yale Bright Star, Gliese), computed locally","asOf":"2026-10-21T05:44:16.877Z","disclaimer":"Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting."}}}},"400":{"description":"A parameter was missing or out of range."},"402":{"description":"Payment Required"},"502":{"description":"The upstream source failed or timed out."}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.0200"},"protocols":[{"x402":{"network":"eip155:8453","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/nearest-stars"}},{"x402":{"network":"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/nearest-stars"}},{"x402":{"network":"eip155:137","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/nearest-stars"}},{"x402":{"network":"eip155:42161","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/nearest-stars"}}]}}},"/star-distance-and-luminosity":{"get":{"operationId":"star_distance_and_luminosity","summary":"From apparent magnitude and parallax (mas): distance, absolute magnitude M = m + 5 + 5 log10(p arcsec), solar luminosity.","description":"From apparent magnitude and parallax (mas): distance, absolute magnitude M = m + 5 + 5 log10(p arcsec), solar luminosity.","tags":["stars","astronomy","luminosity","parallax"],"parameters":[{"name":"apparentMagnitude","in":"query","required":true,"description":"Apparent visual magnitude m, -30 to 30","schema":{"type":"number"}},{"name":"parallaxMas","in":"query","required":true,"description":"Parallax in milliarcseconds, 0.01 to 1000","schema":{"type":"number"}}],"responses":{"200":{"description":"The answer.","content":{"application/json":{"schema":{"type":"object","properties":{"verdict":{"type":["null","string"]},"summary":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"apparentMagnitude":{"type":["null","number"]},"parallaxMas":{"type":["null","number"]},"distanceParsecs":{"type":["null","number"]},"distanceLightYears":{"type":["null","number"]},"absoluteMagnitude":{"type":["null","number"]},"luminositySolarVisual":{"type":["null","number"]},"distanceModulus":{"type":["null","number"]},"degraded":{"type":["boolean","null"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"source":{"type":["null","string"]},"asOf":{"type":["null","string"]},"disclaimer":{"type":["null","string"]}}},"example":{"verdict":"COMPUTED","summary":"Distance 2.637 pc (8.6 ly), absolute magnitude 1.454, luminosity 22.4 Sun (visual).","reasons":["M = m + 5 + 5 log10(parallax in arcseconds); L/Lsun = 10^((4.83 - M)/2.5)."],"apparentMagnitude":-1.44,"parallaxMas":379.21,"distanceParsecs":2.6371,"distanceLightYears":8.601,"absoluteMagnitude":1.4544,"luminositySolarVisual":22.3996,"distanceModulus":-2.8944,"degraded":false,"notChecked":["interstellar extinction (dust dimming), which makes distant stars look fainter than this assumes","the parallax measurement error: small parallaxes have large relative error","…1 more"],"source":"HYG database v4.1 (CC BY-SA 4.0: Hipparcos, Yale Bright Star, Gliese), computed locally","asOf":"2026-10-21T05:44:17.128Z","disclaimer":"Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting."}}}},"400":{"description":"A parameter was missing or out of range."},"402":{"description":"Payment Required"},"502":{"description":"The upstream source failed or timed out."}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.0200"},"protocols":[{"x402":{"network":"eip155:8453","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-distance-and-luminosity"}},{"x402":{"network":"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-distance-and-luminosity"}},{"x402":{"network":"eip155:137","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-distance-and-luminosity"}},{"x402":{"network":"eip155:42161","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-distance-and-luminosity"}}]}}},"/star-lookup":{"get":{"operationId":"star_lookup","summary":"Look up a star by name, Bayer (Alpha CMa), HR, HIP, HD or Gliese number: magnitude, spectrum, J2000 position, distance.","description":"Look up a star by name, Bayer (Alpha CMa), HR, HIP, HD or Gliese number: magnitude, spectrum, J2000 position, distance.","tags":["stars","astronomy","hipparcos","catalog"],"parameters":[{"name":"q","in":"query","required":true,"description":"Sirius, Alpha Canis Majoris, alp CMa, 9 CMa, HR 2491, HIP 32349, HD 48915, Gl 244A","schema":{"type":"string"}}],"responses":{"200":{"description":"The answer.","content":{"application/json":{"schema":{"type":"object","properties":{"verdict":{"type":["null","string"]},"summary":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"input":{"type":["null","string"]},"matchedBy":{"type":["null","string"]},"matches":{"type":["array","null"],"items":{"type":"object","properties":{"name":{"type":["null","string"]},"designations":{"type":["null","object"],"properties":{"proper":{"type":["null","string"]},"bayer":{"type":["null","string"]},"flamsteed":{"type":["null","string"]},"hr":{"type":["null","number"]},"hip":{"type":["null","number"]},"hd":{"type":["null","number"]},"gliese":{"type":["null","string"]}}},"constellation":{"type":["null","string"]},"constellationAbbr":{"type":["null","string"]},"apparentMagnitude":{"type":["null","number"]},"spectralType":{"type":["null","string"]},"colorIndexBV":{"type":["null","number"]},"raDeg":{"type":["null","number"]},"raHours":{"type":["null","number"]},"decDeg":{"type":["null","number"]},"epoch":{"type":["null","string"]},"parallaxMas":{"type":["null","number"]},"distanceParsecs":{"type":["null","number"]},"distanceLightYears":{"type":["null","number"]},"absoluteMagnitude":{"type":["null","number"]},"luminositySolar":{"type":["null","number"]},"properMotionRaMasPerYr":{"type":["null","number"]},"properMotionDecMasPerYr":{"type":["null","number"]},"radialVelocityKmS":{"type":["null","number"]}}}},"attribution":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"source":{"type":["null","string"]},"asOf":{"type":["null","string"]},"disclaimer":{"type":["null","string"]}}},"example":{"verdict":"FOUND","summary":"Sirius: V -1.44, A0m..., Canis Major, 8.6 ly.","reasons":["Matched by proper name."],"input":"Sirius","matchedBy":"proper name","matches":[{"name":"Sirius","designations":{"proper":"Sirius","bayer":"Alpha Canis Majoris","flamsteed":"9 Canis Majoris","hr":2491,"hip":32349,"hd":48915,"gliese":"Gl 244A"},"constellation":"Canis Major","constellationAbbr":"CMa","apparentMagnitude":-1.44,"spectralType":"A0m...","colorIndexBV":0.009,"raDeg":101.28722,"raHours":6.75248,"decDeg":-16.71612,"epoch":"J2000.0","parallaxMas":379.2,"distanceParsecs":2.6371,"distanceLightYears":8.6,"absoluteMagnitude":1.454,"luminositySolar":22.824,"properMotionRaMasPerYr":-546.01,"properMotionDecMasPerYr":-1223.08,"radialVelocityKmS":-9.4}],"attribution":"Star data: HYG database v4.1 by David Nash (astronexus), CC BY-SA 4.0; bright (V<=6.5) and nearest-200 subset, built 2026-10-21.","degraded":false,"notChecked":["stars fainter than magnitude 6.5 unless among the 200 nearest","positions at today's date: J2000 coordinates are not corrected for proper motion","…2 more"],"source":"HYG database v4.1 (CC BY-SA 4.0: Hipparcos, Yale Bright Star, Gliese), computed locally","asOf":"2026-10-21T05:44:17.391Z","disclaimer":"Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting."}}}},"400":{"description":"A parameter was missing or out of range."},"402":{"description":"Payment Required"},"502":{"description":"The upstream source failed or timed out."}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.0200"},"protocols":[{"x402":{"network":"eip155:8453","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-lookup"}},{"x402":{"network":"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-lookup"}},{"x402":{"network":"eip155:137","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-lookup"}},{"x402":{"network":"eip155:42161","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-lookup"}}]}}},"/star-visibility-from-latitude":{"get":{"operationId":"star_visibility_from_latitude","summary":"Whether a star (or declination) ever rises above the horizon from a latitude, circumpolar status, and max altitude.","description":"Whether a star (or declination) ever rises above the horizon from a latitude, circumpolar status, and max altitude.","tags":["stars","astronomy","visibility","latitude"],"parameters":[{"name":"latitudeDeg","in":"query","required":true,"description":"Observer latitude, -90 (south) to 90 (north)","schema":{"type":"number"}},{"name":"star","in":"query","required":false,"description":"Star name or designation (Sirius, HR 2491); or give declinationDeg","schema":{"type":"string"}},{"name":"declinationDeg","in":"query","required":false,"description":"Declination in degrees if no star is named","schema":{"type":"number"}}],"responses":{"200":{"description":"The answer.","content":{"application/json":{"schema":{"type":"object","properties":{"verdict":{"type":["null","string"]},"summary":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"latitudeDeg":{"type":["null","number"]},"declinationDeg":{"type":["null","number"]},"star":{"type":["null","object"],"properties":{"name":{"type":["null","string"]},"designations":{"type":["null","object"],"properties":{"proper":{"type":["null","string"]},"bayer":{"type":["null","string"]},"flamsteed":{"type":["null","string"]},"hr":{"type":["null","number"]},"hip":{"type":["null","number"]},"hd":{"type":["null","number"]},"gliese":{"type":["null","string"]}}},"constellation":{"type":["null","string"]},"constellationAbbr":{"type":["null","string"]},"apparentMagnitude":{"type":["null","number"]},"spectralType":{"type":["null","string"]},"colorIndexBV":{"type":["null","number"]},"raDeg":{"type":["null","number"]},"raHours":{"type":["null","number"]},"decDeg":{"type":["null","number"]},"epoch":{"type":["null","string"]},"parallaxMas":{"type":["null","number"]},"distanceParsecs":{"type":["null","number"]},"distanceLightYears":{"type":["null","number"]},"absoluteMagnitude":{"type":["null","number"]},"luminositySolar":{"type":["null","number"]},"properMotionRaMasPerYr":{"type":["null","number"]},"properMotionDecMasPerYr":{"type":["null","number"]},"radialVelocityKmS":{"type":["null","number"]}}},"maxAltitudeDeg":{"type":["null","number"]},"minAltitudeDeg":{"type":["null","number"]},"everAboveHorizon":{"type":["boolean","null"]},"circumpolar":{"type":["boolean","null"]},"attribution":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"source":{"type":["null","string"]},"asOf":{"type":["null","string"]},"disclaimer":{"type":["null","string"]}}},"example":{"verdict":"RISES_AND_SETS","summary":"From latitude 40: Sirius rises and sets, reaching 33.28 deg at its highest.","reasons":["Highest altitude = 90 - |latitude - declination| at upper culmination; lowest = |latitude + declination| - 90 at lower culmination."],"latitudeDeg":40,"declinationDeg":-16.71612,"star":{"name":"Sirius","designations":{"proper":"Sirius","bayer":"Alpha Canis Majoris","flamsteed":"9 Canis Majoris","hr":2491,"hip":32349,"hd":48915,"gliese":"Gl 244A"},"constellation":"Canis Major","constellationAbbr":"CMa","apparentMagnitude":-1.44,"spectralType":"A0m...","colorIndexBV":0.009,"raDeg":101.28722,"raHours":6.75248,"decDeg":-16.71612,"epoch":"J2000.0","parallaxMas":379.2,"distanceParsecs":2.6371,"distanceLightYears":8.6,"absoluteMagnitude":1.454,"luminositySolar":22.824,"properMotionRaMasPerYr":-546.01,"properMotionDecMasPerYr":-1223.08,"radialVelocityKmS":-9.4},"maxAltitudeDeg":33.28,"minAltitudeDeg":-66.72,"everAboveHorizon":true,"circumpolar":false,"attribution":"Star data: HYG database v4.1 by David Nash (astronexus), CC BY-SA 4.0; bright (V<=6.5) and nearest-200 subset, built 2026-10-21.","degraded":false,"notChecked":["atmospheric refraction (lifts objects about 0.5 deg at the horizon), the local horizon and terrain, and the dip of the horizon at height","darkness: whether the sky is dark when the star is up (season and time of night)","…2 more"],"source":"HYG database v4.1 (CC BY-SA 4.0: Hipparcos, Yale Bright Star, Gliese), computed locally","asOf":"2026-10-21T05:44:17.655Z","disclaimer":"Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting."}}}},"400":{"description":"A parameter was missing or out of range."},"402":{"description":"Payment Required"},"502":{"description":"The upstream source failed or timed out."}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.0200"},"protocols":[{"x402":{"network":"eip155:8453","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-visibility-from-latitude"}},{"x402":{"network":"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-visibility-from-latitude"}},{"x402":{"network":"eip155:137","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-visibility-from-latitude"}},{"x402":{"network":"eip155:42161","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/star-visibility-from-latitude"}}]}}},"/stars-in-constellation":{"get":{"operationId":"stars_in_constellation","summary":"List catalogued stars in an IAU constellation (name or 3-letter code), brightest first, with an optional named-only filter.","description":"List catalogued stars in an IAU constellation (name or 3-letter code), brightest first, with an optional named-only filter.","tags":["stars","constellations","astronomy","catalog"],"parameters":[{"name":"constellation","in":"query","required":true,"description":"Orion, Ori, Ursa Major, UMa","schema":{"type":"string"}},{"name":"namedOnly","in":"query","required":false,"description":"Only stars with a proper name","schema":{"type":"boolean"}},{"name":"limit","in":"query","required":false,"description":"Results 1 to 100 (default 30)","schema":{"type":"integer"}}],"responses":{"200":{"description":"The answer.","content":{"application/json":{"schema":{"type":"object","properties":{"verdict":{"type":["null","string"]},"summary":{"type":["null","string"]},"reasons":{"type":["array","null"]},"constellation":{"type":["null","object"],"properties":{"abbr":{"type":["null","string"]},"name":{"type":["null","string"]},"genitive":{"type":["null","string"]}}},"total":{"type":["null","number"]},"stars":{"type":["array","null"],"items":{"type":"object","properties":{"name":{"type":["null","string"]},"designations":{"type":["null","object"],"properties":{"proper":{"type":["null","string"]},"bayer":{"type":["null","string"]},"flamsteed":{"type":["null","string"]},"hr":{"type":["null","number"]},"hip":{"type":["null","number"]},"hd":{"type":["null","number"]},"gliese":{"type":["null","string"]}}},"constellation":{"type":["null","string"]},"constellationAbbr":{"type":["null","string"]},"apparentMagnitude":{"type":["null","number"]},"spectralType":{"type":["null","string"]},"colorIndexBV":{"type":["null","number"]},"raDeg":{"type":["null","number"]},"raHours":{"type":["null","number"]},"decDeg":{"type":["null","number"]},"epoch":{"type":["null","string"]},"parallaxMas":{"type":["null","number"]},"distanceParsecs":{"type":["null","number"]},"distanceLightYears":{"type":["null","number"]},"absoluteMagnitude":{"type":["null","number"]},"luminositySolar":{"type":["null","number"]},"properMotionRaMasPerYr":{"type":["null","number"]},"properMotionDecMasPerYr":{"type":["null","number"]},"radialVelocityKmS":{"type":["null","number"]}}}},"attribution":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"source":{"type":["null","string"]},"asOf":{"type":["null","string"]},"disclaimer":{"type":["null","string"]}}},"example":{"verdict":"LISTED","summary":"Orion (Ori): 10 catalogued star(s), brightest Rigel (0.18).","reasons":[],"constellation":{"abbr":"Ori","name":"Orion","genitive":"Orionis"},"total":10,"stars":[{"name":"Rigel","designations":{"proper":"Rigel","bayer":"Beta Orionis","flamsteed":"19 Orionis","hr":1713,"hip":24436,"hd":34085,"gliese":null},"constellation":"Orion","constellationAbbr":"Ori","apparentMagnitude":0.18,"spectralType":"B8Ia","colorIndexBV":-0.03,"raDeg":78.63447,"raHours":5.2423,"decDeg":-8.20164,"epoch":"J2000.0","parallaxMas":3.78,"distanceParsecs":264.5503,"distanceLightYears":862.85,"absoluteMagnitude":-6.933,"luminositySolar":51665.424,"properMotionRaMasPerYr":1.87,"properMotionDecMasPerYr":-0.56,"radialVelocityKmS":21},{"name":"Betelgeuse","designations":{"proper":"Betelgeuse","bayer":"Alpha Orionis","flamsteed":"58 Orionis","hr":2061,"hip":27989,"hd":39801,"gliese":null},"constellation":"Orion","constellationAbbr":"Ori","apparentMagnitude":0.45,"spectralType":"M2Ib","colorIndexBV":1.5,"raDeg":88.79294,"raHours":5.91953,"decDeg":7.40706,"epoch":"J2000.0","parallaxMas":6.55,"distanceParsecs":152.6718,"distanceLightYears":497.95,"absoluteMagnitude":-5.469,"luminositySolar":13415.288,"properMotionRaMasPerYr":27.33,"properMotionDecMasPerYr":10.86,"radialVelocityKmS":21}],"attribution":"Star data: HYG database v4.1 by David Nash (astronexus), CC BY-SA 4.0; bright (V<=6.5) and nearest-200 subset, built 2026-10-21.","degraded":false,"notChecked":["stars fainter than magnitude 6.5","asterisms that cross constellation borders (the Big Dipper uses stars from Ursa Major only; Orion's belt is inside Orion)","…1 more"],"source":"HYG database v4.1 (CC BY-SA 4.0: Hipparcos, Yale Bright Star, Gliese), computed locally","asOf":"2026-10-21T05:44:17.919Z","disclaimer":"Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting."}}}},"400":{"description":"A parameter was missing or out of range."},"402":{"description":"Payment Required"},"502":{"description":"The upstream source failed or timed out."}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.0200"},"protocols":[{"x402":{"network":"eip155:8453","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/stars-in-constellation"}},{"x402":{"network":"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/stars-in-constellation"}},{"x402":{"network":"eip155:137","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/stars-in-constellation"}},{"x402":{"network":"eip155:42161","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/stars-in-constellation"}}]}}},"/stars-near-sky-point":{"get":{"operationId":"stars_near_sky_point","summary":"Cone search: stars within a radius (max 30 deg) of an RA/Dec J2000 point, nearest first, with separations.","description":"Cone search: stars within a radius (max 30 deg) of an RA/Dec J2000 point, nearest first, with separations.","tags":["stars","astronomy","cone-search","coordinates"],"parameters":[{"name":"raDeg","in":"query","required":true,"description":"Right ascension in degrees, 0 to 360 (hours x 15)","schema":{"type":"number"}},{"name":"decDeg","in":"query","required":true,"description":"Declination in degrees, -90 to 90","schema":{"type":"number"}},{"name":"radiusDeg","in":"query","required":false,"description":"Cone radius in degrees, 0.01 to 30 (default 2)","schema":{"type":"number"}},{"name":"limit","in":"query","required":false,"description":"Maximum results 1 to 100 (default 25)","schema":{"type":"integer"}},{"name":"maxMagnitude","in":"query","required":false,"description":"Only stars brighter than this magnitude (default 6.5)","schema":{"type":"number"}}],"responses":{"200":{"description":"The answer.","content":{"application/json":{"schema":{"type":"object","properties":{"verdict":{"type":["null","string"]},"summary":{"type":["null","string"]},"reasons":{"type":["array","null"]},"center":{"type":["null","object"],"properties":{"raDeg":{"type":["null","number"]},"decDeg":{"type":["null","number"]}}},"radiusDeg":{"type":["null","number"]},"total":{"type":["null","number"]},"stars":{"type":["array","null"],"items":{"type":"object","properties":{"separationDeg":{"type":["null","number"]},"name":{"type":["null","string"]},"designations":{"type":["null","object"],"properties":{"proper":{"type":["null","string"]},"bayer":{"type":["null","string"]},"flamsteed":{"type":["null","string"]},"hr":{"type":["null","number"]},"hip":{"type":["null","number"]},"hd":{"type":["null","number"]},"gliese":{}}},"constellation":{"type":["null","string"]},"constellationAbbr":{"type":["null","string"]},"apparentMagnitude":{"type":["null","number"]},"spectralType":{"type":["null","string"]},"colorIndexBV":{"type":["null","number"]},"raDeg":{"type":["null","number"]},"raHours":{"type":["null","number"]},"decDeg":{"type":["null","number"]},"epoch":{"type":["null","string"]},"parallaxMas":{"type":["null","number"]},"distanceParsecs":{"type":["null","number"]},"distanceLightYears":{"type":["null","number"]},"absoluteMagnitude":{"type":["null","number"]},"luminositySolar":{"type":["null","number"]},"properMotionRaMasPerYr":{"type":["null","number"]},"properMotionDecMasPerYr":{"type":["null","number"]},"radialVelocityKmS":{"type":["null","number"]}}}},"attribution":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"source":{"type":["null","string"]},"asOf":{"type":["null","string"]},"disclaimer":{"type":["null","string"]}}},"example":{"verdict":"FOUND","summary":"3 star(s) within 2 deg; nearest Alnilam at 0.0001 deg.","reasons":[],"center":{"raDeg":84.0533,"decDeg":-1.2019},"radiusDeg":2,"total":3,"stars":[{"separationDeg":0.0001,"name":"Alnilam","designations":{"proper":"Alnilam","bayer":"Epsilon Orionis","flamsteed":"46 Orionis","hr":1903,"hip":26311,"hd":37128,"gliese":null},"constellation":"Orion","constellationAbbr":"Ori","apparentMagnitude":1.69,"spectralType":"B0Ia","colorIndexBV":-0.184,"raDeg":84.05339,"raHours":5.60356,"decDeg":-1.20192,"epoch":"J2000.0","parallaxMas":1.65,"distanceParsecs":606.0606,"distanceLightYears":1976.71,"absoluteMagnitude":-7.223,"luminositySolar":67483.873,"properMotionRaMasPerYr":1.49,"properMotionDecMasPerYr":-1.06,"radialVelocityKmS":26},{"separationDeg":1.3561,"name":"Alnitak","designations":{"proper":"Alnitak","bayer":"Zeta Orionis","flamsteed":"50 Orionis","hr":1948,"hip":26727,"hd":37742,"gliese":null},"constellation":"Orion","constellationAbbr":"Ori","apparentMagnitude":1.74,"spectralType":"O9.5Ib SB","colorIndexBV":-0.199,"raDeg":85.1897,"raHours":5.67931,"decDeg":-1.94257,"epoch":"J2000.0","parallaxMas":4.43,"distanceParsecs":225.7336,"distanceLightYears":736.24,"absoluteMagnitude":-5.028,"luminositySolar":8937.17,"properMotionRaMasPerYr":3.99,"properMotionDecMasPerYr":2.54,"radialVelocityKmS":18}],"attribution":"Star data: HYG database v4.1 by David Nash (astronexus), CC BY-SA 4.0; bright (V<=6.5) and nearest-200 subset, built 2026-10-21.","degraded":false,"notChecked":["stars fainter than magnitude 6.5 (except the 200 nearest)","proper motion since J2000 (small for most stars, up to arcminutes for the fastest)","…1 more"],"source":"HYG database v4.1 (CC BY-SA 4.0: Hipparcos, Yale Bright Star, Gliese), computed locally","asOf":"2026-10-21T05:44:18.184Z","disclaimer":"Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting."}}}},"400":{"description":"A parameter was missing or out of range."},"402":{"description":"Payment Required"},"502":{"description":"The upstream source failed or timed out."}},"x-payment-info":{"price":{"mode":"fixed","currency":"USD","amount":"0.0200"},"protocols":[{"x402":{"network":"eip155:8453","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/stars-near-sky-point"}},{"x402":{"network":"solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/stars-near-sky-point"}},{"x402":{"network":"eip155:137","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/stars-near-sky-point"}},{"x402":{"network":"eip155:42161","scheme":"exact","currency":"USDC","endpoint":"https://star-catalog.x402tookit.com/stars-near-sky-point"}}]}}}}}