Moon Phases

A custom indicator created by TrendSpider Team on TrendSpider. You can import this custom indicator into your TrendSpider account. Don't have TrendSpider? Create an account first, then import the custom indicator.

The "Moon Phases" indicator plots moon phase symbols (e.g., new moon, first quarter, full moon) on a price chart by calculating the moon's cycle using the Julian date and a known new moon reference (January 6, 2000). It marks key phases—new moon, first quarter, full moon, and last quarter—with corresponding emoji symbols and registers signals for potential trading strategies. Note: AI-generated, not QA-tested, for informational use only.

Source code

This indicator had been implemented by TrendSpider Team in JavaScript on TrendSpider. Check out the developer documentation to learn more about JS on TrendSpider.

describe_indicator('Moon Phases', 'price', { shortName: 'Moon Phases' });

const moment = library('moment-timezone');

// Function to calculate moon phase
function getMoonPhase(julianDate) {
    const knownNewMoon = 2451550.1; // Julian date of a known new moon (January 6, 2000, 18:14 UT)
    const synodicMonth = 29.53058867; // Length of a synodic month in days

    const daysSinceNewMoon = julianDate - knownNewMoon;
    const newMoons = Math.floor(daysSinceNewMoon / synodicMonth);
    const phase = daysSinceNewMoon - (newMoons * synodicMonth);

    return phase / synodicMonth;
}

// Convert date to Julian date with time precision
function toJulianDate(timestamp) {
    // Convert timestamp to UT using moment-timezone
    const date = moment.tz(timestamp * 1000, "UTC");

    const year = date.year();
    const month = date.month() + 1; // Moment months are 0-11, Julian needs 1-12
    const day = date.date();
    const hours = date.hours();
    const minutes = date.minutes();
    const seconds = date.seconds();

    // Simplified Julian date calculation with time adjustment
    let a = Math.floor((14 - month) / 12);
    let y = year + 4800 - a;
    let m = month + 12 * a - 3;

    let jd = day + Math.floor((153 * m + 2) / 5) + 365 * y + Math.floor(y / 4) - Math.floor(y / 100) + Math.floor(y / 400) - 32045;

    // Add the fractional part of the day
    const dayFraction = (hours + (minutes / 60) + (seconds / 3600)) / 24;
    return jd + dayFraction;
}

// Paint moon phase symbols based on moon phase
const symbols = series_of(null);

const newMoonSignal = series_of(false);
const firstQuarterSignal = series_of(false);
const fullMoonSignal = series_of(false);
const lastQuarterSignal = series_of(false);

let previousPhase = null;

for (let i = 0; i < time.length; i++) {
    const julianDate = toJulianDate(time[i]);
    const moonPhase = getMoonPhase(julianDate);

    if (previousPhase === null || Math.floor(previousPhase * 8) !== Math.floor(moonPhase * 8)) {
        let symbol;

        // Define all eight moon phases with tighter ranges for key phases
        if (moonPhase < 0.025 || moonPhase >= 0.975) {
            symbol = '🌑'; // New moon
            newMoonSignal[i] = true;
        } else if (moonPhase >= 0.025 && moonPhase < 0.225) {
            symbol = '🌒'; // Waxing crescent moon
        } else if (moonPhase >= 0.225 && moonPhase < 0.275) {
            symbol = '🌓'; // First quarter moon
            firstQuarterSignal[i] = true;
        } else if (moonPhase >= 0.275 && moonPhase < 0.475) {
            symbol = '🌔'; // Waxing gibbous moon
        } else if (moonPhase >= 0.475 && moonPhase < 0.525) {
            symbol = '🌕'; // Full moon
            fullMoonSignal[i] = true;
        } else if (moonPhase >= 0.525 && moonPhase < 0.725) {
            symbol = '🌖'; // Waning gibbous moon
        } else if (moonPhase >= 0.725 && moonPhase < 0.775) {
            symbol = '🌗'; // Last quarter moon
            lastQuarterSignal[i] = true;
        } else if (moonPhase >= 0.775 && moonPhase < 0.975) {
            symbol = '🌘'; // Waning crescent moon
        }

        symbols[i] = symbol;
    }

    previousPhase = moonPhase;
}

// Paint the moon phase symbols on the chart
paint(symbols, {
    name: 'Moon Phase',
    style: 'labels_above',
    color: 'white',
    thickness: 1
});

// Register signals for potential use in alerts or strategies
register_signal(newMoonSignal, 'New Moon');
register_signal(firstQuarterSignal, 'First Quarter Moon');
register_signal(fullMoonSignal, 'Full Moon');
register_signal(lastQuarterSignal, 'Last Quarter Moon');