Returns coming in from 1000's of Nm away.....impossible?

[CYYZGUY]

I know with tropospheric ducting and skip, in the radio comunication world, anything can happen.  With ADS-B being line of sight....is it completely impossible to get the odd return from far far away?

Occasionally I get the odd return like this.

regards,

Jason

[Lou]

I doubt it is anything to do with ducting or anything like that, more like faulty or miss set equipment. A while back Bluebird aircargo frequently used to show as in the middle of Africa sometimes even showing a trail so it could not have been that far from me