src/Birthday/Birthday.php
public static function parseConstellation($month, $day): string
    {
        switch ($month) {
            case 1:
                return $day >= 20 ? 'Aquarius' : 'Capricorn';
            case 2:
                return $day >= 19 ? 'Pisces' : 'Aquarius';
            case 3:
                return $day >= 21 ? 'Aries' : 'Pisces';
            case 4:
                return $day >= 20 ? 'Taurus' : 'Aries';
            case 5:
                return $day >= 21 ? 'Gemini' : 'Taurus';
            case 6:
                return $day >= 22 ? 'Cancer' : 'Gemini';
            case 7:
                return $day >= 23 ? 'Leo' : 'Cancer';
            case 8:
                return $day >= 23 ? 'Virgo' : 'Leo';
            case 9:
                return $day >= 23 ? 'Libra' : 'Virgo';
            case 10:
                return $day >= 24 ? 'Scorpio' : 'Libra';
            case 11:
                return $day >= 23 ? 'Sagittarius' : 'Scorpio';
            case 12:
                return $day >= 22 ? 'Capricorn' : 'Sagittarius';
        }
        throw new \InvalidArgumentException("Invalid month and day: $month , $day");
    }
public static function parseConstellation($month, $day): string
    {
        switch ($month) {
            case 1:
                return $day >= 20 ? 'Aquarius' : 'Capricorn';
            case 2:
                return $day >= 19 ? 'Pisces' : 'Aquarius';
            case 3:
                return $day >= 21 ? 'Aries' : 'Pisces';
            case 4:
                return $day >= 20 ? 'Taurus' : 'Aries';
            case 5:
                return $day >= 21 ? 'Gemini' : 'Taurus';
            case 6:
                return $day >= 22 ? 'Cancer' : 'Gemini';
            case 7:
                return $day >= 23 ? 'Leo' : 'Cancer';
            case 8:
                return $day >= 23 ? 'Virgo' : 'Leo';
            case 9:
                return $day >= 23 ? 'Libra' : 'Virgo';
            case 10:
                return $day >= 24 ? 'Scorpio' : 'Libra';
            case 11:
                return $day >= 23 ? 'Sagittarius' : 'Scorpio';
            case 12:
                return $day >= 22 ? 'Capricorn' : 'Sagittarius';
        }
        throw new \InvalidArgumentException("Invalid month and day: $month , $day");
    }
Parse constellation by the given month and day

@param  int                         $month
@param  int                         $day
@throws \InvalidArgumentException
@return string