I am the center of gravity,
hold a capital situation in Vienna,
and as I am foremost in every victory,
am allowed by all to be invaluable.
Though I am invisible,
I am clearly seen in the midst of a river.
I could name three who are in love with me
and have three associates in vice.
It is vain that you seek me for I have long been in heaven,
yet even now lie embalmed in the grave.
What am I?
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