Asteroid 1999 AN_{10} was observed until the angular distance from
the sun became .
It will be again at
from the
Sun after the beginning of June; by that time the uncertainty of its
position on the sky will grow to 1.5 arc minutes (corresponding to
), that is any new observation will significantly contribute
to an improvement of the orbit. It is very likely that the
observations made in the second half of this year will constrain the
orbit well enough to predict accurately the 2027 encounter. This
implies that some of the returns of the Table will be discarded as
incompatible with the observations; in fact, most of them if the 2027
encounter is not very deep.

The problem, however, will not go away, because all along the LOV there are possible encounters occurring later, almost every six months. We have analysed with our global method the same multiple solutions over a time span of 50 years after 2027, and found 165 possible returns, out of which 117 in the moderate to low stretching region. This situation is qualitatively stable: whatever the actual orbit is, it will not be possible to predict with certainty the returns after the next close approach for a time span longer than a few decades.

Since at least one node of 1999 AN_{10} will remain close to the
orbit of the Earth for centuries, this asteroid shall have to be
monitored, by observations and computations, for a very long time. It
is conceivable that at some time in the future a decision could be
made to deflect it; but, a deflection decreasing the depth of some
specific close approach could increase the impact risk at a later
date. Thus before such a decision can be contemplated we need to
better understand the theory of resonant and non-resonant returns,
which has only been outlined in this paper.