Jellyfish in the marina

Its the time of year when the Jellyfish bloom begins. Here you can see some jellyfish in the Constitution Marina. Does anyone know which species this is?

I did a little research and found that they are moon jellyfish (Aurelia_aurita). Also there is an article in the Charlestown Patch concerning the annual bloom of these jellyfish. Apparently one jellyfish can lay 45,000 eggs in one day. Taken straight from the article in the Charlestown patch - The jellyfish might be compared to a butterfly, Tony LaCasse, media relations director at the aquarium has said. The medusa, the ‘bell’ has a short life, maybe just a few weeks. When the medusa spawns, its eggs float to the bottom of the harbor or attach themselves to hard surfaces, like pilings on the piers. A few more stages follow until the following spring when ‘saucer-like’ jellies emerge, eat like crazy, and become the ‘bells’ floating around in the harbor.