IV (Implied Volatility/Vega) is simply the markets way of giving a premium or discount to the price of contracts.
When IV is relatively high, the options market is pricing in the potential for a lot of fluctuation in the underlying equity’s price during the life of that particular contract. This causes option premiums to inflate. Low IV = just the opposite....the market is pricing in a "non-event" – nothing unusual expected and premiums on options will be lower.
IV fluctuates throughout the day as well.....ie. it's always inflated in the first 30-45 minutes of trade.
The constellation sounds like a proprietary matrix for listing these numbers. I could be wrong there.
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