Get Instagram data via CURL
I don't think that file_get_contents is so much slower then curl. In the end it depends on the response time of the server you're trying to get the information and how much requests you do.
So i would prefer file_get_contents in your case its much easier and needs less code. And the much important thing... its working ;)
$result = file_get_contents('https://www.instagram.com/nasa/media/');