diff --git a/README.md b/README.md
index bcee163..b209984 100644
--- a/README.md
+++ b/README.md
@@ -68,6 +68,11 @@ da = MS.new(
 |  | telescope_diameter | Attribute | Telescope dish diameter | m | 10.0 | float | - | - |
 |  | telescope_coordinates | Attribute | Telescope ITRS coordinates | m | (0.0, 0.0, 0.0) | "tuple[float, float, float]" | - | - |
 | ASTE specific | aste_cabin_temperature | Coordinate | [ASTE] Cabin temperature | K | 0.0 | numpy.ndarray | (time,) | float64 |
+|  | aste_obs_group | Attribute | [ASTE] Observation group | - | "" | str | - | - |
+|  | aste_obs_id | Attribute | [ASTE] Observation ID | - | "" | str | - | - |
+|  | aste_obs_project | Attribute | [ASTE] Observation project | - | "" | str | - | - |
+|  | aste_obs_table | Attribute | [ASTE] Observation table (= observation) | - | "" | str | - | - |
+|  | aste_obs_user | Attribute | [ASTE] Observer (= observer) | - | "" | str | - | - |
 |  | aste_subref_x | Coordinate | [ASTE] Subreflector offset of X axis | mm | 0.0 | numpy.ndarray | (time,) | float64 |
 |  | aste_subref_y | Coordinate | [ASTE] Subreflector offset of Y axis | mm | 0.0 | numpy.ndarray | (time,) | float64 |
 |  | aste_subref_z | Coordinate | [ASTE] Subreflector offset of Z axis | mm | 0.0 | numpy.ndarray | (time,) | float64 |
diff --git a/dems/d2.py b/dems/d2.py
index f9b4e38..ad0ef8a 100644
--- a/dems/d2.py
+++ b/dems/d2.py
@@ -359,6 +359,11 @@ class MS(AsDataArray):
     telescope_coordinates: Attr[Tuple[float, float, float]] = ASTE_ITRS_COORDS
     # ASTE specific
     aste_cabin_temperature: Coordof[AsteCabinTemperature] = 0.0
+    aste_obs_group: Attr[str] = ""
+    aste_obs_id: Attr[str] = ""
+    aste_obs_project: Attr[str] = ""
+    aste_obs_table: Attr[str] = ""
+    aste_obs_user: Attr[str] = ""
     aste_subref_x: Coordof[AsteSubrefX] = 0.0
     aste_subref_y: Coordof[AsteSubrefY] = 0.0
     aste_subref_z: Coordof[AsteSubrefZ] = 0.0
@@ -410,6 +415,12 @@ class Cube(AsDataArray):
     observer: Attr[str] = ""
     project: Attr[str] = ""
     object: Attr[str] = ""
+    # ASTE specific
+    aste_obs_group: Attr[str] = ""
+    aste_obs_id: Attr[str] = ""
+    aste_obs_project: Attr[str] = ""
+    aste_obs_table: Attr[str] = ""
+    aste_obs_user: Attr[str] = ""
     # DESHIMA 2.0 specific
     d2_mkid_type: Coordof[D2MkidType] = ""
     d2_mkid_frequency: Coordof[D2MkidFrequency] = 0.0