Source: GA
Don’t touch the vRShabha
Offer prayers to Vṛṣabha from far & then offer prayers to Bhagavān, followed by a method if circumbulation called somasūtra pradakṣiṇam. No touching of Vṛṣabhadeva or even stepping on his shadow or even allowing one’s shadow to mingle with Vṛṣabhadeva’s.
somasūtra circumbulation
It should be the default because the Āgama actually advises people against crossing the gomukhī.
वृषं चण्डं वृषं चैव
सोमसूत्रं पुनर्वृषम्।
चण्डं च सोमसूत्रं च
पुनश्चण्डं पुनर्वृषम्।।
इति शिवरहस्ये।R C
R G
R C
G
R C
RAs per the above marked symbols this pradaxiNam is to be done. First saluting the R^iShabha devar (Holy Bull) go anti-clockwise and salute chaNdIshar (not crossing the gomukhi). Now return in the clockwise manner salute R^iShabham and continue clockwise till the gomukhi (not cross it again). Then return in anti-clockwise direction salute the R^iShabham again and proceed towards chaNdIshar. From there return back clockwise without worshiping R^iShabham and reach the gomukhi. Finally return back anti-clockwise from there to salute R^iShabham and continue to chaNdIshar and return back to R^iShabham and worship the shiva li.ngam (at the altar) by viewing through the space between the two horns of the Holy bull. This is one pradaxiNam. Three such times pradaxiNam to be done.
If you carefully observe the curve traced by doing the pradaxiNam is very similar to the periphery of the crescent. Hence this way of circumambulating is called soma sUtra pradaxiNam.
In Kerala temples, they don’t allow crossing the Gomuki on any day. They tie a rope to stop people from doing so.