Incorrect moon altitude

[artem78]

When I made chart of moon position during the day, I noticed that sometimes there are incorrect altitude values. For example for lat 59.95, lon 30.32 and date 2017/10/15:

2017-10-15T23:32:00+00:00  alt=-2.145  diff=+0.122
2017-10-15T23:33:00+00:00  alt=-2.009  diff=+0.136
2017-10-15T23:34:00+00:00  alt=-1.818  diff=+0.191
2017-10-15T23:35:00+00:00  alt=-26.623  diff=-24.805    <----
2017-10-15T23:36:00+00:00  alt=-1.924  diff=+24.699
2017-10-15T23:37:00+00:00  alt=-1.734  diff=+0.190
2017-10-15T23:38:00+00:00  alt=-1.598  diff=+0.137
2017-10-15T23:39:00+00:00  alt=-1.475  diff=+0.123

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