On the day of Sid Vicious Death we see Transiting Uranus conjunct his Progressed Ascendant. His progressed Ascendant was already making a tight conjunction to his Natal North Node.
All of this is taking place in the sign of Scorpio in his 1st house, signifying a shocking(Uranus) death(Scorpio) to the physical self(1st house).
*** Obviously this is not the only interpretation for these aspects. He could have chosen a sudden(Uranus), Self(1st house) transformation(Scorpio).
Death is only one of many ways to transform self.
Take a look at his Tri-Wheel showing his Transits-Progressions-Natal positions.
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