Why is Astaxanthin more powerful than other antioxidants?

Astaxanthin is especially effective at squelching singlet oxygen, a particularly dangerous free radical that can damage nearly every part of the body. In this regard, astaxanthin has been scientifically shown to be:*

40 times stronger than beta-carotene
100 times stronger than vitamin E
550 times stronger than green tea (EGCG)
800 times stronger than CoQ10
6,000 times stronger than vitamin C