Why Current Transformer Star Point is Earthed

Please explain further. I am just a poor naif who has never seen a current transformer with a star point. I doubt that any such animal exists, but I don't know.

I refer to earlier a CR4 discussion,on "Why we must earth one terminal at secondary side of current transformer?" Several answers received are quoted for ready reference: 1. I think it's a safety precaution against possible 'open circuit' on the CT secondary side, which can lead to generation of dangerously high voltage. 2. It is provided to flow the earth fault current. 3. During a secondary open circuit on one CT, a very high transient voltage would appear across all the three phase CTs as they are interconnected through the loads. If you earth one terminal of the secondary of all the three phase CTs, the insulation need to be done only for phase voltage and not for line voltage. This greatly reduces the size and insulation cost of the CT. There is a dedicated IEEE Standard on this topic. 4. CT Primary and secondary is linked though stray capacitance and resistance of insulator. If CT secondary is not earthed, the primary voltage may induce high potential in secondary winding. To keep the secondary voltage at designed rating (say 110 v) against the earth, secondary must be earthed. It appears,both the questions are same. Please clarify.