The majority of spatio-temporal DBMS assume objects to be precise

but this simplification can’t work in many military

navigation and environmental applications.Many forms of spatio-temporal data can’t be measured exactly

and in these kinds of objects exists spatio-temporal indeterminacy.Spatio-temporal uncertainty management is a new topic for researchers on spatio-temporal databases.The current method based on Fuzzy Sets is not well applicable because it imposes strict restrictions on the objects’ uncertainty.In this paper

a new abstract model of uncertain spatio-temporal objects is presented.This model is based on the Grey Sets and is more applicable for the presentation and manipulation of partial unknown spatio-temporal objects.This paper first gives the formal definition of uncertain abstract data types based on the Grey Sets

such as the definition of base types

spatial types and spatio-temporal types.Then we take a glimpse at the aspect of uncertain spatio-temporal analysis.Finally

examples of uncertain query is presented.