data/constellations.py

"""Constellation catalog for Nova Scotia / eastern Canada skies.

Phase 5 — Targets tab data source.
Keyed as a list so order is preserved; use CONSTELLATIONS_BY_NAME for lookups.
"""

CONSTELLATIONS = [
    {
        "name": "Orion",
        "season": "Winter",
        "best_months": [11, 12, 1, 2, 3],
        "description": "The Hunter, one of the most recognizable constellations in the sky. Visible from every inhabited continent.",
        "mythology": "In Greek myth, Orion was a giant hunter placed among the stars by Zeus. Hera sent a scorpion to kill him — which is why Orion and Scorpius are never in the sky at the same time.",
        "how_to_find": [
            "Face south around 9–11 pm in winter.",
            "Find three diagonal stars in a row — that's Orion's Belt (Alnitak, Alnilam, Mintaka).",
            "Above the Belt is reddish Betelgeuse (shoulder); below is blue-white Rigel (foot).",
            "Look below the Belt for a faint fuzzy 'star' — that's the Orion Nebula (M42).",
        ],
        "deep_sky": ["Orion Nebula (M42)", "Horsehead Nebula", "Flame Nebula (NGC 2024)", "Running Man Nebula"],
        "bortle_needed": 4,
    },
    {
        "name": "Ursa Major",
        "season": "Year-round",
        "best_months": [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12],
        "description": "The Great Bear, home to the famous Big Dipper asterism. Circumpolar from Nova Scotia — never sets below the horizon.",
        "mythology": "Zeus transformed Callisto into a bear to protect her from Hera's jealousy, then placed her in the sky. Her son Arcas became Ursa Minor nearby.",
        "how_to_find": [
            "Locate the Big Dipper — a ladle shape of seven bright stars high in the northern sky.",
            "The two outer stars of the bowl (Dubhe & Merak) are the 'pointer stars' — they point directly to Polaris.",
            "Follow the arc of the handle to 'Arc to Arcturus' in spring and summer.",
        ],
        "deep_sky": ["Bode's Galaxy (M81)", "Cigar Galaxy (M82)", "Owl Nebula (M97)", "Pinwheel Galaxy (M101)"],
        "bortle_needed": 4,
    },
    {
        "name": "Cassiopeia",
        "season": "Year-round",
        "best_months": [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12],
        "description": "The Queen — a distinctive W or M shape of five bright stars circumpolar from Nova Scotia. Sits opposite the Big Dipper across Polaris.",
        "mythology": "Cassiopeia was the vain queen of Ethiopia who boasted she was more beautiful than the sea nymphs (Nereids), angering Poseidon.",
        "how_to_find": [
            "Look north for a bright W (or M, depending on time of year) shape.",
            "It lies directly across Polaris from the Big Dipper.",
            "The middle star of the W points roughly toward the Andromeda Galaxy.",
        ],
        "deep_sky": ["Pacman Nebula (NGC 281)", "Owl Cluster (NGC 457)", "Heart Nebula (IC 1805)", "Soul Nebula (IC 1848)"],
        "bortle_needed": 3,
    },
    {
        "name": "Andromeda",
        "season": "Fall",
        "best_months": [8, 9, 10, 11, 12],
        "description": "The Chained Maiden, famous for hosting M31 — the Andromeda Galaxy, our nearest large galactic neighbor at 2.5 million light-years.",
        "mythology": "Princess Andromeda was chained to a rock as sacrifice to Cetus the sea monster. Perseus slew the monster and rescued her.",
        "how_to_find": [
            "Find the Great Square of Pegasus high in the southern sky in autumn.",
            "From the top-left star of the Square (Alpheratz), hop two stars northeast.",
            "Look for a faint elongated smudge — binoculars reveal M31's oval glow.",
            "Averted vision (looking slightly to the side) shows the galaxy's full extent.",
        ],
        "deep_sky": ["Andromeda Galaxy (M31)", "M32 (satellite galaxy)", "M110 (satellite galaxy)", "Blue Snowball Nebula (NGC 7662)"],
        "bortle_needed": 4,
    },
    {
        "name": "Cygnus",
        "season": "Summer",
        "best_months": [6, 7, 8, 9, 10],
        "description": "The Swan, featuring the Northern Cross asterism. Deneb marks its tail and anchors the Summer Triangle. The Milky Way runs right through it.",
        "mythology": "Often identified as Zeus disguised as a swan to court Leda; also the transformed Orpheus placed in the sky after his death.",
        "how_to_find": [
            "In summer, look nearly overhead for the bright bluish-white star Deneb.",
            "Trace a large cross shape — the Northern Cross — with Deneb at the top.",
            "The Milky Way flows through Cygnus; scan slowly with binoculars for star clouds.",
        ],
        "deep_sky": ["North America Nebula (NGC 7000)", "Veil Nebula (NGC 6992)", "Crescent Nebula (NGC 6888)", "Blinking Planetary (NGC 6826)"],
        "bortle_needed": 4,
    },
    {
        "name": "Lyra",
        "season": "Summer",
        "best_months": [6, 7, 8, 9],
        "description": "The Lyre, a small but brilliant constellation anchored by Vega — the 5th-brightest star in the night sky and part of the Summer Triangle.",
        "mythology": "Represents the lyre of Orpheus, the legendary musician whose music could charm gods, beasts, and rivers.",
        "how_to_find": [
            "Find the brilliant bluish-white star Vega — it's nearly overhead in summer.",
            "Just east of Vega is a small parallelogram of four fainter stars — the body of the lyre.",
            "Between two of those stars sits the Ring Nebula — visible in a 4-inch scope.",
        ],
        "deep_sky": ["Ring Nebula (M57)", "Globular Cluster M56", "Double-double star Epsilon Lyrae"],
        "bortle_needed": 5,
    },
    {
        "name": "Sagittarius",
        "season": "Summer",
        "best_months": [6, 7, 8, 9],
        "description": "The Archer, pointing toward the densest part of the Milky Way and the galactic center. Rich in nebulae and star clusters.",
        "mythology": "Often identified as the centaur Chiron or the satyr Crotus, a skilled hunter who invented archery.",
        "how_to_find": [
            "Look low in the south-southwest in summer after dark — it never gets very high from Nova Scotia.",
            "Find the 'Teapot' asterism: a kettle-shaped group of eight stars.",
            "The steam rising from the Teapot's spout is the Milky Way itself — aim binoculars there.",
        ],
        "deep_sky": ["Lagoon Nebula (M8)", "Trifid Nebula (M20)", "Omega Nebula (M17)", "Sagittarius Star Cloud (M24)"],
        "bortle_needed": 5,
    },
    {
        "name": "Scorpius",
        "season": "Summer",
        "best_months": [6, 7, 8],
        "description": "The Scorpion — a long, curving constellation with the bright red star Antares at its heart. Skims low on the southern horizon from Nova Scotia.",
        "mythology": "The scorpion sent by Gaia to slay Orion the Hunter. Zeus placed both in the sky on opposite sides so they never meet.",
        "how_to_find": [
            "Look very low in the south in July–August, just after dusk.",
            "Antares — a distinctly reddish-orange supergiant — marks the heart.",
            "The tail curves to the left ending in two stars (Shaula & Lesath) forming the stinger.",
        ],
        "deep_sky": ["Butterfly Cluster (M6)", "Ptolemy Cluster (M7)", "Cat's Paw Nebula (NGC 6334)"],
        "bortle_needed": 5,
    },
    {
        "name": "Pegasus",
        "season": "Fall",
        "best_months": [8, 9, 10, 11],
        "description": "The Winged Horse, dominating the autumn sky. Its most famous feature is the Great Square, a large nearly empty box of four stars.",
        "mythology": "Pegasus was born from the blood of Medusa when Perseus beheaded her. The winged horse was later tamed by the hero Bellerophon.",
        "how_to_find": [
            "In autumn, look high in the south for four medium-bright stars forming a large square.",
            "The Great Square of Pegasus is surprisingly empty inside — count the stars within it to gauge sky darkness.",
            "One corner star (Alpheratz) is actually shared with Andromeda.",
        ],
        "deep_sky": ["Great Pegasus Cluster (M15)", "Stephan's Quintet (NGC 7317 group)"],
        "bortle_needed": 5,
    },
    {
        "name": "Gemini",
        "season": "Winter",
        "best_months": [12, 1, 2, 3, 4],
        "description": "The Twins, marked by the two bright stars Castor and Pollux — easy to spot as a pair high above Orion in winter.",
        "mythology": "Castor and Pollux were twin half-brothers: Pollux was immortal (son of Zeus) and Castor mortal. When Castor died, Pollux shared his immortality.",
        "how_to_find": [
            "Look above and to the left of Orion for two bright stars side by side.",
            "The slightly brighter, yellower star (Pollux) is on the right; whiter Castor is to the left.",
            "Trace two lines of stars extending south from each twin toward Orion.",
        ],
        "deep_sky": ["Shoe-Buckle Cluster (M35)", "Eskimo Nebula (NGC 2392)", "Jellyfish Nebula (IC 443)"],
        "bortle_needed": 4,
    },
    {
        "name": "Taurus",
        "season": "Winter",
        "best_months": [11, 12, 1, 2, 3],
        "description": "The Bull, containing two of the sky's finest naked-eye clusters: the Pleiades (Seven Sisters) and the Hyades.",
        "mythology": "Zeus transformed himself into a magnificent white bull to abduct Europa, princess of Phoenicia, and carry her to Crete.",
        "how_to_find": [
            "Follow Orion's Belt stars to the upper-right — they point straight to reddish Aldebaran, the Bull's eye.",
            "The V-shaped Hyades cluster forms the Bull's face around Aldebaran.",
            "Continue further upper-right for the compact blue Pleiades cluster.",
        ],
        "deep_sky": ["Pleiades (M45)", "Crab Nebula (M1)", "Hyades Cluster"],
        "bortle_needed": 3,
    },
    {
        "name": "Leo",
        "season": "Spring",
        "best_months": [2, 3, 4, 5, 6],
        "description": "The Lion, a prominent spring constellation with the bright star Regulus at its heart. Easy to find thanks to its distinctive sickle shape.",
        "mythology": "The Nemean Lion, killed by Heracles (Hercules) as the first of his Twelve Labors. Its hide was impervious to weapons.",
        "how_to_find": [
            "In spring, face south around 10 pm and look for a backward question-mark shape (the Sickle) — this is Leo's head and mane.",
            "Regulus, a blue-white star, sits at the bottom of the Sickle.",
            "A right-angled triangle of stars to the left marks the Lion's hindquarters.",
        ],
        "deep_sky": ["Leo Triplet (M65, M66, NGC 3628)", "M95", "M96"],
        "bortle_needed": 5,
    },
    {
        "name": "Boötes",
        "season": "Spring",
        "best_months": [3, 4, 5, 6, 7],
        "description": "The Herdsman, containing Arcturus — the 4th-brightest star in the entire night sky and the brightest in the northern hemisphere.",
        "mythology": "Boötes is often identified as Arcas, son of Zeus and Callisto, who almost hunted his own mother (transformed into Ursa Major) before Zeus intervened.",
        "how_to_find": [
            "Follow the arc of the Big Dipper's handle outward — 'Arc to Arcturus'.",
            "Arcturus is an unmistakable golden-orange star, the first very bright star you reach.",
            "Boötes forms a kite or ice-cream-cone shape of stars north of Arcturus.",
        ],
        "deep_sky": ["Arcturus (closest giant star to Earth)", "NGC 5466 globular cluster"],
        "bortle_needed": 4,
    },
]

# Fast lookup by name
CONSTELLATIONS_BY_NAME = {c["name"]: c for c in CONSTELLATIONS}