cannot get user_registered date from get_user_meta

Question

I am trying to display the user_registered date from get_user_meta but it always displays as empty. If I try another field I do get a value so not sure why I don't see anything for the date. If I check the database there is definitely a date.

$data = array();
$user_query = new WP_User_Query( array( 'meta_key' => 'location', 'meta_value' => $my_location, 'orderby' => 'meta_value_num', 'order' => 'DESC' ));
$authors = $user_query->get_results();
     foreach ($authors as $user) {
        $register_date = get_user_meta($user->ID, 'user_registered', true);

         $data[] = array(
             'registered' => $register_date,
         );
}
return $data;

Answer 1

user_registered is not a meta field, it is a field in the users table.
Try:

$register_date = $user->user_registered;