In 2012, the mercapto radical, SH, became one of the
of a previously unknown interstellar molecule to be made with the new
SOFIA airborne observatory.
Neufeld and co-workers identified it in the giant
molecular cloud W49A via a rotational transition in the
The initial detection of SH in an astrophysical source was reported in 2000 by
Yamamura et al. They
found the species in the atmosphere of the
R Andromedae, via its ro-vibrational spectrum. A detection
of SH on the atmosphere of our own sun was reported in 2000 by
Berdyugina & Livingston using UV transitions.
SH is also known as sulfur monohydride and as the
sulfanyl radical. The singly-occupied orbital is shown to the
right. It very much resembles a S 3p orbital.