Whirlpool Galaxy
The Whirlpool Galaxy , also known as Messier 51a , M51a , and NGC 5194 , is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus . 
<triplet> Whirlpool Galaxy <subj> spiral galaxy <obj> instance of <triplet> grand-design <subj> spiral galaxy <obj> subclass of <triplet> Seyfert 2 <subj> active galactic nucleus <obj> subclass of