You need to import moment() the function and Moment the class separately in TS.
I found a note in the typescript docs here.
/*~ Note that ES6 modules cannot directly export callable functions
*~ This file should be imported using the CommonJS-style:
*~ import x = require('someLibrary');
So the code to import moment js into typescript actually looks like this:
import { Moment } from 'moment'
....
let moment = require('moment');
...
interface SomeTime {
aMoment: Moment,
}
...
fn() {
...
someTime.aMoment = moment(...);
...
}