Shadows dissapear when looking directly at it.

I use point light to have a shadow effect from the moon to the earth. I have the camera centered to the earth and I see the shadow, when I press play, the shadow dissapears, when I view the planet at an angle the shadow comes back. I am unable to see the shadow when looking directly at it. Reminds me of the blindspot of the eye, unable to see certain emitted colors like from the blinking usb stick when centered on it. What is causing the shadow to dissapear when centered on it?

Have you tried looking into your project quality settings ?
There is a shadow option that may come in handy