The model class has a method called freshTimestamp. It will return a new Carbon timestamp with the current date and time. The same method is used for setting the created_at and updated_at fields inside your model. You can use this method inside your own code if you wish.

<?php
$book = new Book();
$book->title = 'The world of Pringles';
$book->published_at = $book->freshTimestamp();