What is the datetime format of posting tweets via php

rajat_tripathi · 2012-08-21T09:37:32.000Z

i am getting the following datetime on my tweets -

Wednesday 30 Nov -0001 00:00

Please let me know the default datetime format

niall · 2016-02-06T21:48:09.975Z

niall · 2016-02-06T21:56:20.261Z