Handle non-ICRS coordinates in query functions

CHANGES.rst

@@ -143,6 +143,8 @@ utils
 
 - Raising cleaner errors earlier when server returns with error. [#3284]
 
+- ``return_frame`` parameter in ``utils.commons.parse_coordinates`` returns coordinates in the specified frame. [#3164]
+
 
 0.4.10 (2025-03-18)
 ===================
@@ -2279,4 +2281,4 @@ Infrastructure, Utility and Other Changes and Additions
 0.1 (2013-09-19)
 ================
 
-- Initial release.  Includes features!
+- Initial release.  Includes features!

astroquery/mast/collections.py

@@ -204,7 +204,7 @@ def query_region_async(self, coordinates, *, radius=0.2*u.deg, catalog="Hsc",
         """
 
         # Put coordinates and radius into consistent format
-        coordinates = commons.parse_coordinates(coordinates)
+        coordinates = commons.parse_coordinates(coordinates, return_frame='icrs')
 
         # if radius is just a number we assume degrees
         radius = coord.Angle(radius, u.deg)

astroquery/mast/missions.py

@@ -245,7 +245,7 @@ def query_region_async(self, coordinates, *, radius=3*u.arcmin, limit=5000, offs
         self._validate_criteria(**criteria)
 
         # Put coordinates and radius into consistent format
-        coordinates = commons.parse_coordinates(coordinates)
+        coordinates = commons.parse_coordinates(coordinates, return_frame='icrs')
 
         # If radius is just a number, assume arcminutes
         radius = coord.Angle(radius, u.arcmin)

astroquery/mast/observations.py

@@ -22,8 +22,9 @@
 from astropy.table import Table, Row, vstack
 from astroquery import log
 from astroquery.mast.cloud import CloudAccess
+from astroquery.utils import commons
 
-from ..utils import commons, async_to_sync
+from ..utils import async_to_sync
 from ..utils.class_or_instance import class_or_instance
 from ..exceptions import (InvalidQueryError, RemoteServiceError,
                           NoResultsWarning, InputWarning)
@@ -234,7 +235,7 @@ def query_region_async(self, coordinates, *, radius=0.2*u.deg, pagesize=None, pa
         """
 
         # Put coordinates and radius into consistent format
-        coordinates = commons.parse_coordinates(coordinates)
+        coordinates = commons.parse_coordinates(coordinates, return_frame='icrs')
 
         # if radius is just a number we assume degrees
         radius = coord.Angle(radius, u.deg)
@@ -363,7 +364,7 @@ def query_region_count(self, coordinates, *, radius=0.2*u.deg, pagesize=None, pa
         """
 
         # build the coordinates string needed by ObservationsClass._caom_filtered_position
-        coordinates = commons.parse_coordinates(coordinates)
+        coordinates = commons.parse_coordinates(coordinates, return_frame='icrs')
 
         # if radius is just a number we assume degrees
         radius = coord.Angle(radius, u.deg)

astroquery/mast/tests/test_mast_remote.py

@@ -416,12 +416,6 @@ def test_mast_service_request(self):
         # Is result limited to ten rows
         assert len(result) == 10
 
-        # Are the GALEX observations in the results table
-        assert "GALEX" in result['obs_collection']
-
-        # Are the two GALEX observations with obs_id 6374399093149532160 in the results table
-        assert len(result[np.where(result["obs_id"] == "6374399093149532160")]) == 2
-
     def test_mast_query(self):
         result = Mast.mast_query('Mast.Caom.Cone', ra=184.3, dec=54.5, radius=0.2)
 

astroquery/mast/utils.py

@@ -216,7 +216,8 @@ def parse_input_location(*, coordinates=None, objectname=None, resolver=None):
     Returns
     -------
     response : `~astropy.coordinates.SkyCoord`
-        The given coordinates, or object's location as an `~astropy.coordinates.SkyCoord` object.
+        The given coordinates, or object's location as an `~astropy.coordinates.SkyCoord` object
+        in the ICRS frame.
     """
 
     # Checking for valid input
@@ -232,8 +233,9 @@ def parse_input_location(*, coordinates=None, objectname=None, resolver=None):
     if objectname:
         obj_coord = resolve_object(objectname, resolver=resolver)
 
+    # Parse coordinates, if given
     if coordinates:
-        obj_coord = commons.parse_coordinates(coordinates)
+        obj_coord = commons.parse_coordinates(coordinates, return_frame='icrs')
 
     return obj_coord
 

astroquery/utils/commons.py

@@ -40,7 +40,7 @@
 ASTROPY_LT_7_1_1 = not minversion('astropy', '7.1.1')
 
 
-def parse_coordinates(coordinates):
+def parse_coordinates(coordinates, *, return_frame=None):
     """
     Takes a string or astropy.coordinates object. Checks if the
     string is parsable as an `astropy.coordinates`
@@ -51,6 +51,10 @@ def parse_coordinates(coordinates):
     ----------
     coordinates : str or `astropy.coordinates` object
         Astronomical coordinate
+    return_frame : `astropy.coordinates` frame
+        The frame to return the coordinates in. If None and ``coordinates`` is
+        a string, the frame will be ICRS. If ``coordinates`` is an `astropy.coordinates` object, the
+        frame will be the same as the input object.
 
     Returns
     -------
@@ -93,6 +97,11 @@ def parse_coordinates(coordinates):
             c = SkyCoord(coordinates)
     else:
         raise TypeError("Argument cannot be parsed as a coordinate")
+
+    # Convert to requested frame, if given
+    if return_frame and c.frame.name != return_frame.lower():
+        c = c.transform_to(return_frame)
+
     return c
 
 

astroquery/utils/tests/test_utils.py

@@ -80,6 +80,30 @@ def test_parse_coordinates_4():
     assert c.to_string() == coordinates
 
 
+def test_parse_coordinates_return_frame():
+    # String input should return in icrs frame
+    coords = commons.parse_coordinates('266.40498829 -28.93617776')
+    assert coords.frame.name == 'icrs'
+
+    # SkyCoord input without return_frame should return in original frame
+    galactic = coord.SkyCoord('0 0', unit='deg', frame='galactic')
+    coords = commons.parse_coordinates(galactic)
+    assert coords.frame.name == 'galactic'
+
+    # Parse a SkyCoord in galactic frame into icrs frame
+    galactic = coord.SkyCoord('0 0', unit='deg', frame='galactic')
+    icrs = galactic.transform_to('icrs')  # Expected result
+    coords = commons.parse_coordinates(galactic, return_frame='icrs')
+    assert icrs.ra.deg == coords.ra.deg
+    assert icrs.dec.deg == coords.dec.deg
+    assert galactic.frame.name == 'galactic'
+    assert coords.frame.name == 'icrs'
+
+    # ValueError if transformation fails
+    with pytest.raises(ValueError):
+        coords = commons.parse_coordinates(galactic, return_frame='invalid')
+
+
 col_1 = [1, 2, 3]
 col_2 = [0, 1, 0, 1, 0, 1]
 col_3 = ['v', 'w', 'x', 'y', 'z']