Octoomba
A Cosmic Blooper is an enemy in Super Mario Galaxy. It is practically an alien Blooper. They are seen in various parts of the game and often are spitting space comets at Mario. In some cases, if Mario destroys some, a secret might be unveiled, as seen on the Space Boat, where Mario had to eliminate two of them to make a bridge appear.
They can easily be squashed. When defeated, a Coin is always left by them.
Outlook
Cosmic Bloopers are very detailed, odd looking Bloopers. They have smooth skin with a blue head and yellow spots all over. They have a rounded mouth like a Snifit and shoot space comets out of it. They also have yellow, glowing eyes and a small antenna on the top of their head.
They might even be Shroobs, though this is unlikely as these creatures are most likely whatever King Magma Blooper is.