Alien Life Form Mystery Cache

The Cache Will Not Be Found At The Posted Coordinates

I have had this puzzle idea for some time and it wasn't until recently that another puzzle reminded me of it

I hope you like it

There have been many Alien sightings throughout time, Wikipedia even lists one around 1440 BCE but I think the most sightings occurred between 1986 and 1990. Let's see if you agree...

Check out these dates

December 7, 1987

September 21, 1987

January 8,1990

January 11,1988

March 23, 1987

October 20, 1986

November 21, 1988

September 22, 1986

October 6, 1986

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