fix(neo_feed): missing-distance false ALERT + UTC feed window

services/meteor_tracking/neo_feed_client.py

@@ -14,7 +14,7 @@
 
 import logging
 from dataclasses import dataclass
-from datetime import date, datetime, timedelta
+from datetime import date, datetime, timedelta, timezone
 from typing import List, Optional
 
 import aiohttp
@@ -81,7 +81,9 @@ async def fetch_neo_feed(
             List of CloseApproach objects (same type as CAD client)
         """
         if start_date is None:
-            start_date = date.today()
+            # Use UTC (the CAD client and all NEO timing are UTC), so the feed
+            # window cannot shift a day relative to close-approach queries.
+            start_date = datetime.now(timezone.utc).date()
         if end_date is None:
             end_date = start_date + timedelta(days=7)
 
@@ -145,11 +147,22 @@ def _parse_neo_object(self, obj: dict) -> CloseApproach | None:
         d_min = meters.get('estimated_diameter_min')
         d_max = meters.get('estimated_diameter_max')
 
-        # Distance
+        # Distance — prefer the astronomical value, fall back to kilometres.
+        # A missing distance must NOT default to 0: distance_ld == 0 reads as an
+        # extremely close pass and would trip a false ALERT, so skip such objects.
         miss_distance = ca.get('miss_distance', {})
-        dist_au = float(miss_distance.get('astronomical', 0))
-        dist_km = float(miss_distance.get('kilometers', 0))
-        dist_ld = dist_au / LD_TO_AU if dist_au else 0
+        au_raw = miss_distance.get('astronomical')
+        km_raw = miss_distance.get('kilometers')
+        if au_raw is not None:
+            dist_au = float(au_raw)
+            dist_km = float(km_raw) if km_raw is not None else dist_au * AU_TO_KM
+        elif km_raw is not None:
+            dist_km = float(km_raw)
+            dist_au = dist_km / AU_TO_KM
+        else:
+            logger.debug("NEO object missing miss_distance; skipping")
+            return None
+        dist_ld = dist_au / LD_TO_AU
 
         # Velocity
         rel_velocity = ca.get('relative_velocity', {})

tests/unit/test_neo_feed_client.py

@@ -164,6 +164,56 @@ async def test_parse_neo_feed_no_approach_data(self):
         approaches = client._parse_neo_feed(response)
         assert len(approaches) == 0
 
+    @pytest.mark.asyncio
+    async def test_missing_miss_distance_is_skipped_not_alerted(self):
+        """A NEO with no miss_distance must be SKIPPED, not defaulted to 0
+        (distance 0 would read as an extremely close pass and trip a false ALERT)."""
+        client = NEOFeedClient()
+        response = {
+            'near_earth_objects': {
+                '2026-03-23': [{
+                    'neo_reference_id': 'no-distance',
+                    'name': 'no-distance',
+                    'absolute_magnitude_h': 22.0,
+                    'estimated_diameter': {'meters': {
+                        'estimated_diameter_min': 10, 'estimated_diameter_max': 20}},
+                    'is_potentially_hazardous_asteroid': False,
+                    'close_approach_data': [{
+                        'close_approach_date': '2026-03-23',
+                        'relative_velocity': {'kilometers_per_second': '12.0'},
+                        # miss_distance intentionally absent
+                    }],
+                }]
+            }
+        }
+        approaches = client._parse_neo_feed(response)
+        assert approaches == []  # skipped, not a phantom ALERT at distance 0
+
+    @pytest.mark.asyncio
+    async def test_kilometers_only_distance_derives_au(self):
+        """When only kilometres are present, AU/LD are derived (not defaulted to 0)."""
+        client = NEOFeedClient()
+        response = {
+            'near_earth_objects': {
+                '2026-03-23': [{
+                    'neo_reference_id': 'km-only',
+                    'name': 'km-only',
+                    'absolute_magnitude_h': 22.0,
+                    'estimated_diameter': {'meters': {
+                        'estimated_diameter_min': 10, 'estimated_diameter_max': 20}},
+                    'is_potentially_hazardous_asteroid': False,
+                    'close_approach_data': [{
+                        'close_approach_date': '2026-03-23',
+                        'relative_velocity': {'kilometers_per_second': '12.0'},
+                        'miss_distance': {'kilometers': '14959787.07'},  # 0.1 AU
+                    }],
+                }]
+            }
+        }
+        approaches = client._parse_neo_feed(response)
+        assert len(approaches) == 1
+        assert approaches[0].distance_au == pytest.approx(0.1, rel=1e-3)
+
     @pytest.mark.asyncio
     async def test_close_no_session(self):
         """Test closing with no active session."""