Greetings List members

It's been a while since I've last contributed to this list, but I
haven't forgotten about you guys. Matters non-Pali have taken over my
time. But a question has recently come up and I was wondering if any
of you had any thoughts about it.

The Buddha was occasionally referred to as the "Kinsman of the Sun".
Does anyone know how this phrase originated? It may just be a standard
honorific, but apparently the planet mercury is referred to as "Budh"
in Indian astrology, so there may be a play on words here.

Any thoughts.

Your help is appreciated.

Best Wishes

Jim