Golden Cross - Bullish ISATL (Inmarsat)

How long will the bullish trend last? I wouldn't have sold as early as I did, if I knew about the "Golden Cross". I just recently learned about it. :-)

A Golden Cross occurs when the faster moving average (50day) goes above the slower moving average (200day), which is a good indicator to enter a long trade. A bullish Golden Cross (or Death Cross) is the opposite when a slower moving average (200day) goes below the faster moving average (50day), which is a good indicator to exit the trade.

Any recommendations or tips on how to determine a good entry point with a moving average?

Thanks,
Pat