in src/js/modules/belt.js [189:204]
export function closestDate(dates, meridian) {
var arr = dates.map(d => new Date(d))
var diffdate = new Date(meridian);
let resp = arr.sort(function(a, b) {
var distancea = Math.abs(diffdate - a);
var distanceb = Math.abs(diffdate - b);
return distancea - distanceb; // sort a before b when the distance is smaller
});
let fin = resp[0].toISOString()
return fin.slice(0,10)
}