src/Marando/AstroDate/AstroDate.php
public static function equinoxSpring($year)
    {
        $jd = static::equinoxMarch((int)$year, false);

        return AstroDate::jd($jd, TimeScale::TT());
    }
public static function equinoxSpring($year)
    {
        $jd = static::equinoxMarch((int)$year, false);

        return AstroDate::jd($jd, TimeScale::TT());
    }
Creates a new AstroDate instance representing the Spring (Vernal) Equinox
of the provided year

@param  int $year

@return static