हरि ॐ
the word upasana उपासन upa aasana means sitting near by. in
practice this means sitting near Lord or being close to
your chosen diety इष्ट देवत. being aware of His or Her
presence each moment. this is part of practice or साधन.
in Vedic times people performed upasana of Sky, of Sun,
of Wind etc.
The earth could be object of upasana उत्कृष्ट भावन नित्कृष्ट वस्तो:
even a small object could be venerated as if it is great or
Parabrahma.
the form of Lord Krishna could be so venerated as well.
He stands for आकर्षण शक्ति or attraction. he is black.
an object is black because light does not bounce back when
the rays fall on the object. When venerated with भक्ति
devotion, He catches you and does not let go.
the the 11th Skanda of Srimad Bhagavatam explains this
principle when Krishna says