After a photo of the yacht hit Reddit, conversation took off, sparking debates over wealth inequality and the environmental toll of these mega-yachts ... a permanent crew, helicopter pad ...

The Emir owns The Katara, one of the world's most luxurious and expensive mega-yachts, priced at nearly $400 million. This 124-metre vessel includes a helicopter pad and multiple decks for leisure.

The 113 meters long mega yacht has a crew of 45 ... She also has a landing pad and a helicopter, an F18 flight simulator, aquarium, pool, eight open fires with a deposit of five tons of wood ...