  The central star V4334 Sgr (Sakurai's Nova) of the planetary nebula PN
G010.4+04.4 underwent in 1995-1996 the rare event of a very late helium flash.
It represents only one out of two such events during the era of modern
astronomy (the second event was V605 Aql = Nova Aql 1919). All the other
prominent objects of that type originate from events occurring several
thousands of years ago (e.g. A30, A78). Thus it is of special interest for
stellar evolution theory to model the detailed observations obtained during the
last four years. Those models depend essentially on basic stellar parameters
like effective temperature, surface gravity and stellar radius. Most of them
depend strongly on the assumed distance to the object. Some models may give
some constraints on this parameter, but most of them depend on the assumption
as input parameter. Hence to determine a relyable distance is of considerable
significance.This should be obtained through models that give us lower and
upper boundaries, or through means which are independent of models. The
detailed review, by using every kind of determination available up to now,
leads to a galactic foreground extinction of E(B-V) = 0.75+/-0.05 and a
distance of D =2.0 (-0.6;+1.0) kpc.
