When dealing with ephemeris, always provide in UTC

B612-Asteroid-Institute · Aug 1, 2024 · ac69b6a · ac69b6a
1 parent 1988db5
commit ac69b6a
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Showing 2 changed files with 7 additions and 4 deletions.
diff --git a/src/adam_core/orbits/query/horizons.py b/src/adam_core/orbits/query/horizons.py
@@ -226,17 +226,14 @@ def query_horizons_ephemeris(
         ignore_index=True,
     )
 
-    # Horizons produces UTC but we use tdb everywhere
-    epochs = Timestamp.from_jd(pa.array(dfs["datetime_jd"]), scale="utc").rescale("tdb")
-
     ephemeris = Ephemeris.from_kwargs(
         orbit_id=dfs["orbit_id"],
         object_id=dfs["targetname"],
         # Convert from minutes to days
         light_time=dfs["lighttime"] / 1440,
         alpha=dfs["alpha"],
         coordinates=SphericalCoordinates.from_kwargs(
-            time=epochs,
+            time=Timestamp.from_jd(pa.array(dfs["datetime_jd"]), scale="utc"),
             lon=dfs["RA"],
             lat=dfs["DEC"],
             origin=Origin.from_kwargs(code=dfs["observatory_code"]),

diff --git a/src/adam_core/propagator/propagator.py b/src/adam_core/propagator/propagator.py
@@ -220,6 +220,12 @@ def _generate_ephemeris(
                 spherical_coordinates, SphericalCoordinates, frame_out="equatorial"
             )
 
+            # Ephemeris are generally compared in UTC, so rescale the time
+            spherical_coordinates = spherical_coordinates.set_column(
+                "time",
+                spherical_coordinates.time.rescale("utc"),
+            )
+
             if isinstance(orbits, Orbits):
 
                 ephemeris = Ephemeris.from_kwargs(