Date.prototype.getUTCDay()

const date1 = new Date("August 19, 1975 23:15:30 GMT+11:00");
const date2 = new Date("August 19, 1975 23:15:30 GMT-11:00");

// Tuesday
console.log(date1.getUTCDay());
// Expected output: 2

// Wednesday
console.log(date2.getUTCDay());
// Expected output: 3

getUTCDay()

const today = new Date();
const weekday = today.getUTCDay();