diff --git a/demo/python/astronomy.py b/demo/python/astronomy.py
index 6b8568fe..960fcfd6 100644
--- a/demo/python/astronomy.py
+++ b/demo/python/astronomy.py
@@ -4503,6 +4503,7 @@ def HelioVector(body, time):
     body : Body
         The celestial body whose heliocentric position is to be calculated:
         The Sun, Moon, EMB, SSB, or any of the planets.
+        Also allowed to be a user-defined star created by #DefineStar.
     time : Time
         The time at which to calculate the heliocentric position.
 
@@ -4910,6 +4911,7 @@ def HelioState(body, time):
         Supported values are `Body.Sun`, `Body.SSB`, `Body.Moon`, `Body.EMB`, and all planets:
         `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`,
         `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`.
+        Also allowed to be a user-defined star created by #DefineStar.
     time : Time
         The date and time for which to calculate position and velocity.
 
@@ -4956,6 +4958,10 @@ def HelioState(body, time):
             time
         )
 
+    if _IsUserDefinedStar(body):
+        vec = HelioVector(body, time)
+        return StateVector(vec.x, vec.y, vec.z, 0.0, 0.0, 0.0, time)
+
     raise InvalidBodyError(body)
 
 
diff --git a/generate/template/astronomy.c b/generate/template/astronomy.c
index 874e2a3c..e3d004e0 100644
--- a/generate/template/astronomy.c
+++ b/generate/template/astronomy.c
@@ -4294,6 +4294,7 @@ astro_state_vector_t Astronomy_BaryState(astro_body_t body, astro_time_t time)
  *      Supported values are `BODY_SUN`, `BODY_MOON`, `BODY_EMB`, `BODY_SSB`, and all planets:
  *      `BODY_MERCURY`, `BODY_VENUS`, `BODY_EARTH`, `BODY_MARS`, `BODY_JUPITER`,
  *      `BODY_SATURN`, `BODY_URANUS`, `BODY_NEPTUNE`, `BODY_PLUTO`.
+ *      Also allowed to be a user-defined star created by #Astronomy_DefineStar.
  * @param time
  *      The date and time for which to calculate position and velocity.
  * @return
@@ -4306,6 +4307,17 @@ astro_state_vector_t Astronomy_HelioState(astro_body_t body, astro_time_t time)
     major_bodies_t bary;
     body_state_t planet, earth;
 
+    if (IsUserDefinedStar(body))
+    {
+        astro_vector_t vec = Astronomy_HelioVector(body, time);
+        state.x = vec.x;
+        state.y = vec.y;
+        state.z = vec.z;
+        state.vx = state.vy = state.vz = 0.0;
+        state.status = vec.status;
+        return state;
+    }
+
     switch (body)
     {
     case BODY_SUN:
diff --git a/generate/template/astronomy.cs b/generate/template/astronomy.cs
index 3f4f1c59..19610afb 100644
--- a/generate/template/astronomy.cs
+++ b/generate/template/astronomy.cs
@@ -4414,6 +4414,7 @@ $ASTRO_IAU_DATA()
         /// <param name="body">
         /// A body for which to calculate a heliocentric position:
         /// the Sun, Moon, EMB, SSB, or any of the planets.
+        /// Also allowed to be a user-defined star created by #Astronomy.DefineStar.
         /// </param>
         /// <param name="time">The date and time for which to calculate the position.</param>
         /// <returns>A heliocentric position vector of the center of the given body.</returns>
@@ -4855,6 +4856,7 @@ $ASTRO_IAU_DATA()
         /// Supported values are `Body.Sun`, `Body.Moon`, `Body.EMB`, `Body.SSB`, and all planets:
         /// `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`,
         /// `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`.
+        /// Also allowed to be a user-defined star created by #Astronomy.DefineStar.
         /// </param>
         /// <param name="time">
         /// The date and time for which to calculate position and velocity.
@@ -4913,6 +4915,11 @@ $ASTRO_IAU_DATA()
                     );
 
                 default:
+                    if (IsUserDefinedStar(body))
+                    {
+                        AstroVector vec = HelioVector(body, time);
+                        return new StateVector(vec.x, vec.y, vec.z, 0.0, 0.0, 0.0, time);
+                    }
                     throw new InvalidBodyException(body);
             }
         }
diff --git a/generate/template/astronomy.kt b/generate/template/astronomy.kt
index 285ec154..4a479306 100644
--- a/generate/template/astronomy.kt
+++ b/generate/template/astronomy.kt
@@ -4827,6 +4827,7 @@ private fun solarSystemBarycenterState(time: Time): StateVector {
  * @param body
  * A body for which to calculate a heliocentric position:
  * the Sun, Moon, EMB, SSB, or any of the planets.
+ * Also allowed to be a user-defined star created by [defineStar].
  *
  * @param time
  * The date and time for which to calculate the position.
@@ -4894,6 +4895,7 @@ fun helioDistance(body: Body, time: Time): Double {
  * Supported values are [Body.Sun], [Body.Moon], [Body.EMB], [Body.SSB], and all planets:
  * [Body.Mercury], [Body.Venus], [Body.Earth], [Body.Mars], [Body.Jupiter],
  * [Body.Saturn], [Body.Uranus], [Body.Neptune], [Body.Pluto].
+ * Also allowed to be a user-defined star created by [defineStar].
  *
  * @param time
  * The date and time for which to calculate position and velocity.
@@ -4903,8 +4905,13 @@ fun helioDistance(body: Body, time: Time): Double {
  * The positions are expressed in AU.
  * The velocities are expressed in AU/day.
  */
-fun helioState(body: Body, time: Time): StateVector =
-    when (body) {
+fun helioState(body: Body, time: Time): StateVector {
+    if (isUserDefinedStar(body)) {
+        val vec = helioVector(body, time)
+        return StateVector(vec.x, vec.y, vec.z, 0.0, 0.0, 0.0, time)
+    }
+
+    return when (body) {
         Body.Sun   -> StateVector(0.0, 0.0, 0.0, 0.0, 0.0, 0.0, time)
         Body.Pluto -> calcPluto(time, true)
         Body.Moon  -> helioEarthState(time) + geoMoonState(time)
@@ -4912,6 +4919,7 @@ fun helioState(body: Body, time: Time): StateVector =
         Body.SSB   -> solarSystemBarycenterState(time)
         else       -> StateVector(calcVsopPosVel(vsopModel(body), time.tt), time)
     }
+}
 
 
 /**
diff --git a/generate/template/astronomy.py b/generate/template/astronomy.py
index cd4544e9..887aea47 100644
--- a/generate/template/astronomy.py
+++ b/generate/template/astronomy.py
@@ -2461,6 +2461,7 @@ def HelioVector(body, time):
     body : Body
         The celestial body whose heliocentric position is to be calculated:
         The Sun, Moon, EMB, SSB, or any of the planets.
+        Also allowed to be a user-defined star created by #DefineStar.
     time : Time
         The time at which to calculate the heliocentric position.
 
@@ -2868,6 +2869,7 @@ def HelioState(body, time):
         Supported values are `Body.Sun`, `Body.SSB`, `Body.Moon`, `Body.EMB`, and all planets:
         `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`,
         `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`.
+        Also allowed to be a user-defined star created by #DefineStar.
     time : Time
         The date and time for which to calculate position and velocity.
 
@@ -2914,6 +2916,10 @@ def HelioState(body, time):
             time
         )
 
+    if _IsUserDefinedStar(body):
+        vec = HelioVector(body, time)
+        return StateVector(vec.x, vec.y, vec.z, 0.0, 0.0, 0.0, time)
+
     raise InvalidBodyError(body)
 
 
diff --git a/source/c/README.md b/source/c/README.md
index 9fd99f58..a575e777 100644
--- a/source/c/README.md
+++ b/source/c/README.md
@@ -1090,7 +1090,7 @@ Given a body and a time, calculates the position and velocity vectors for the ce
 
 | Type | Parameter | Description |
 | --- | --- | --- |
-| [`astro_body_t`](#astro_body_t) | `body` |  The celestial body whose heliocentric state vector is to be calculated. Supported values are `BODY_SUN`, `BODY_MOON`, `BODY_EMB`, `BODY_SSB`, and all planets: `BODY_MERCURY`, `BODY_VENUS`, `BODY_EARTH`, `BODY_MARS`, `BODY_JUPITER`, `BODY_SATURN`, `BODY_URANUS`, `BODY_NEPTUNE`, `BODY_PLUTO`.  | 
+| [`astro_body_t`](#astro_body_t) | `body` |  The celestial body whose heliocentric state vector is to be calculated. Supported values are `BODY_SUN`, `BODY_MOON`, `BODY_EMB`, `BODY_SSB`, and all planets: `BODY_MERCURY`, `BODY_VENUS`, `BODY_EARTH`, `BODY_MARS`, `BODY_JUPITER`, `BODY_SATURN`, `BODY_URANUS`, `BODY_NEPTUNE`, `BODY_PLUTO`. Also allowed to be a user-defined star created by [`Astronomy_DefineStar`](#Astronomy_DefineStar).  | 
 | [`astro_time_t`](#astro_time_t) | `time` |  The date and time for which to calculate position and velocity.  | 
 
 
diff --git a/source/c/astronomy.c b/source/c/astronomy.c
index 496f2fe7..4b44a6a1 100644
--- a/source/c/astronomy.c
+++ b/source/c/astronomy.c
@@ -5533,6 +5533,7 @@ astro_state_vector_t Astronomy_BaryState(astro_body_t body, astro_time_t time)
  *      Supported values are `BODY_SUN`, `BODY_MOON`, `BODY_EMB`, `BODY_SSB`, and all planets:
  *      `BODY_MERCURY`, `BODY_VENUS`, `BODY_EARTH`, `BODY_MARS`, `BODY_JUPITER`,
  *      `BODY_SATURN`, `BODY_URANUS`, `BODY_NEPTUNE`, `BODY_PLUTO`.
+ *      Also allowed to be a user-defined star created by #Astronomy_DefineStar.
  * @param time
  *      The date and time for which to calculate position and velocity.
  * @return
@@ -5545,6 +5546,17 @@ astro_state_vector_t Astronomy_HelioState(astro_body_t body, astro_time_t time)
     major_bodies_t bary;
     body_state_t planet, earth;
 
+    if (IsUserDefinedStar(body))
+    {
+        astro_vector_t vec = Astronomy_HelioVector(body, time);
+        state.x = vec.x;
+        state.y = vec.y;
+        state.z = vec.z;
+        state.vx = state.vy = state.vz = 0.0;
+        state.status = vec.status;
+        return state;
+    }
+
     switch (body)
     {
     case BODY_SUN:
diff --git a/source/csharp/README.md b/source/csharp/README.md
index 8bbb1bbd..d35e8d87 100644
--- a/source/csharp/README.md
+++ b/source/csharp/README.md
@@ -724,7 +724,7 @@ of reference, consider using [`Astronomy.BaryState`](#Astronomy.BaryState) inste
 
 | Type | Parameter | Description |
 | --- | --- | --- |
-| [`Body`](#Body) | `body` | The celestial body whose heliocentric state vector is to be calculated. Supported values are `Body.Sun`, `Body.Moon`, `Body.EMB`, `Body.SSB`, and all planets: `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`, `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`. |
+| [`Body`](#Body) | `body` | The celestial body whose heliocentric state vector is to be calculated. Supported values are `Body.Sun`, `Body.Moon`, `Body.EMB`, `Body.SSB`, and all planets: `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`, `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`. Also allowed to be a user-defined star created by [`Astronomy.DefineStar`](#Astronomy.DefineStar). |
 | [`AstroTime`](#AstroTime) | `time` | The date and time for which to calculate position and velocity. |
 
 **Returns:** A structure that contains heliocentric position and velocity vectors.
@@ -746,7 +746,7 @@ If given an invalid value for `body`, this function will throw an [`InvalidBodyE
 
 | Type | Parameter | Description |
 | --- | --- | --- |
-| [`Body`](#Body) | `body` | A body for which to calculate a heliocentric position: the Sun, Moon, EMB, SSB, or any of the planets. |
+| [`Body`](#Body) | `body` | A body for which to calculate a heliocentric position: the Sun, Moon, EMB, SSB, or any of the planets. Also allowed to be a user-defined star created by [`Astronomy.DefineStar`](#Astronomy.DefineStar). |
 | [`AstroTime`](#AstroTime) | `time` | The date and time for which to calculate the position. |
 
 **Returns:** A heliocentric position vector of the center of the given body.
diff --git a/source/csharp/astronomy.cs b/source/csharp/astronomy.cs
index c9a7d41e..f39b5c05 100644
--- a/source/csharp/astronomy.cs
+++ b/source/csharp/astronomy.cs
@@ -5626,6 +5626,7 @@ namespace CosineKitty
         /// <param name="body">
         /// A body for which to calculate a heliocentric position:
         /// the Sun, Moon, EMB, SSB, or any of the planets.
+        /// Also allowed to be a user-defined star created by #Astronomy.DefineStar.
         /// </param>
         /// <param name="time">The date and time for which to calculate the position.</param>
         /// <returns>A heliocentric position vector of the center of the given body.</returns>
@@ -6067,6 +6068,7 @@ namespace CosineKitty
         /// Supported values are `Body.Sun`, `Body.Moon`, `Body.EMB`, `Body.SSB`, and all planets:
         /// `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`,
         /// `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`.
+        /// Also allowed to be a user-defined star created by #Astronomy.DefineStar.
         /// </param>
         /// <param name="time">
         /// The date and time for which to calculate position and velocity.
@@ -6125,6 +6127,11 @@ namespace CosineKitty
                     );
 
                 default:
+                    if (IsUserDefinedStar(body))
+                    {
+                        AstroVector vec = HelioVector(body, time);
+                        return new StateVector(vec.x, vec.y, vec.z, 0.0, 0.0, 0.0, time);
+                    }
                     throw new InvalidBodyException(body);
             }
         }
diff --git a/source/kotlin/doc/helio-state.md b/source/kotlin/doc/helio-state.md
index f2797d7f..fd1e8fd5 100644
--- a/source/kotlin/doc/helio-state.md
+++ b/source/kotlin/doc/helio-state.md
@@ -16,5 +16,5 @@ A state vector that contains heliocentric position and velocity vectors. The pos
 
 | | |
 |---|---|
-| body | The celestial body whose heliocentric state vector is to be calculated. Supported values are [Body.Sun](-body/-sun/index.md), [Body.Moon](-body/-moon/index.md), [Body.EMB](-body/-e-m-b/index.md), [Body.SSB](-body/-s-s-b/index.md), and all planets: [Body.Mercury](-body/-mercury/index.md), [Body.Venus](-body/-venus/index.md), [Body.Earth](-body/-earth/index.md), [Body.Mars](-body/-mars/index.md), [Body.Jupiter](-body/-jupiter/index.md), [Body.Saturn](-body/-saturn/index.md), [Body.Uranus](-body/-uranus/index.md), [Body.Neptune](-body/-neptune/index.md), [Body.Pluto](-body/-pluto/index.md). |
+| body | The celestial body whose heliocentric state vector is to be calculated. Supported values are [Body.Sun](-body/-sun/index.md), [Body.Moon](-body/-moon/index.md), [Body.EMB](-body/-e-m-b/index.md), [Body.SSB](-body/-s-s-b/index.md), and all planets: [Body.Mercury](-body/-mercury/index.md), [Body.Venus](-body/-venus/index.md), [Body.Earth](-body/-earth/index.md), [Body.Mars](-body/-mars/index.md), [Body.Jupiter](-body/-jupiter/index.md), [Body.Saturn](-body/-saturn/index.md), [Body.Uranus](-body/-uranus/index.md), [Body.Neptune](-body/-neptune/index.md), [Body.Pluto](-body/-pluto/index.md). Also allowed to be a user-defined star created by [defineStar](define-star.md). |
 | time | The date and time for which to calculate position and velocity. |
diff --git a/source/kotlin/doc/helio-vector.md b/source/kotlin/doc/helio-vector.md
index be2b6acc..3b9daffa 100644
--- a/source/kotlin/doc/helio-vector.md
+++ b/source/kotlin/doc/helio-vector.md
@@ -20,5 +20,5 @@ The heliocentric position vector of the center of the given body.
 
 | | |
 |---|---|
-| body | A body for which to calculate a heliocentric position: the Sun, Moon, EMB, SSB, or any of the planets. |
+| body | A body for which to calculate a heliocentric position: the Sun, Moon, EMB, SSB, or any of the planets. Also allowed to be a user-defined star created by [defineStar](define-star.md). |
 | time | The date and time for which to calculate the position. |
diff --git a/source/kotlin/src/main/kotlin/io/github/cosinekitty/astronomy/astronomy.kt b/source/kotlin/src/main/kotlin/io/github/cosinekitty/astronomy/astronomy.kt
index eefce652..5b787a12 100644
--- a/source/kotlin/src/main/kotlin/io/github/cosinekitty/astronomy/astronomy.kt
+++ b/source/kotlin/src/main/kotlin/io/github/cosinekitty/astronomy/astronomy.kt
@@ -4827,6 +4827,7 @@ private fun solarSystemBarycenterState(time: Time): StateVector {
  * @param body
  * A body for which to calculate a heliocentric position:
  * the Sun, Moon, EMB, SSB, or any of the planets.
+ * Also allowed to be a user-defined star created by [defineStar].
  *
  * @param time
  * The date and time for which to calculate the position.
@@ -4894,6 +4895,7 @@ fun helioDistance(body: Body, time: Time): Double {
  * Supported values are [Body.Sun], [Body.Moon], [Body.EMB], [Body.SSB], and all planets:
  * [Body.Mercury], [Body.Venus], [Body.Earth], [Body.Mars], [Body.Jupiter],
  * [Body.Saturn], [Body.Uranus], [Body.Neptune], [Body.Pluto].
+ * Also allowed to be a user-defined star created by [defineStar].
  *
  * @param time
  * The date and time for which to calculate position and velocity.
@@ -4903,8 +4905,13 @@ fun helioDistance(body: Body, time: Time): Double {
  * The positions are expressed in AU.
  * The velocities are expressed in AU/day.
  */
-fun helioState(body: Body, time: Time): StateVector =
-    when (body) {
+fun helioState(body: Body, time: Time): StateVector {
+    if (isUserDefinedStar(body)) {
+        val vec = helioVector(body, time)
+        return StateVector(vec.x, vec.y, vec.z, 0.0, 0.0, 0.0, time)
+    }
+
+    return when (body) {
         Body.Sun   -> StateVector(0.0, 0.0, 0.0, 0.0, 0.0, 0.0, time)
         Body.Pluto -> calcPluto(time, true)
         Body.Moon  -> helioEarthState(time) + geoMoonState(time)
@@ -4912,6 +4919,7 @@ fun helioState(body: Body, time: Time): StateVector =
         Body.SSB   -> solarSystemBarycenterState(time)
         else       -> StateVector(calcVsopPosVel(vsopModel(body), time.tt), time)
     }
+}
 
 
 /**
diff --git a/source/python/README.md b/source/python/README.md
index 5013c609..a9063312 100644
--- a/source/python/README.md
+++ b/source/python/README.md
@@ -1758,7 +1758,7 @@ of reference, consider using [`BaryState`](#BaryState) instead.
 
 | Type | Parameter | Description |
 | --- | --- | --- |
-| [`Body`](#Body) | `body` | The celestial body whose heliocentric state vector is to be calculated. Supported values are `Body.Sun`, `Body.SSB`, `Body.Moon`, `Body.EMB`, and all planets: `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`, `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`. |
+| [`Body`](#Body) | `body` | The celestial body whose heliocentric state vector is to be calculated. Supported values are `Body.Sun`, `Body.SSB`, `Body.Moon`, `Body.EMB`, and all planets: `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`, `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`. Also allowed to be a user-defined star created by [`DefineStar`](#DefineStar). |
 | [`Time`](#Time) | `time` | The date and time for which to calculate position and velocity. |
 
 **Returns**: [`StateVector`](#StateVector)
@@ -1781,7 +1781,7 @@ If given an invalid value for `body`, this function raises an exception.
 
 | Type | Parameter | Description |
 | --- | --- | --- |
-| [`Body`](#Body) | `body` | The celestial body whose heliocentric position is to be calculated: The Sun, Moon, EMB, SSB, or any of the planets. |
+| [`Body`](#Body) | `body` | The celestial body whose heliocentric position is to be calculated: The Sun, Moon, EMB, SSB, or any of the planets. Also allowed to be a user-defined star created by [`DefineStar`](#DefineStar). |
 | [`Time`](#Time) | `time` | The time at which to calculate the heliocentric position. |
 
 **Returns**: [`Vector`](#Vector)
diff --git a/source/python/astronomy/astronomy.py b/source/python/astronomy/astronomy.py
index 6b8568fe..960fcfd6 100644
--- a/source/python/astronomy/astronomy.py
+++ b/source/python/astronomy/astronomy.py
@@ -4503,6 +4503,7 @@ def HelioVector(body, time):
     body : Body
         The celestial body whose heliocentric position is to be calculated:
         The Sun, Moon, EMB, SSB, or any of the planets.
+        Also allowed to be a user-defined star created by #DefineStar.
     time : Time
         The time at which to calculate the heliocentric position.
 
@@ -4910,6 +4911,7 @@ def HelioState(body, time):
         Supported values are `Body.Sun`, `Body.SSB`, `Body.Moon`, `Body.EMB`, and all planets:
         `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`, `Body.Jupiter`,
         `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`.
+        Also allowed to be a user-defined star created by #DefineStar.
     time : Time
         The date and time for which to calculate position and velocity.
 
@@ -4956,6 +4958,10 @@ def HelioState(body, time):
             time
         )
 
+    if _IsUserDefinedStar(body):
+        vec = HelioVector(body, time)
+        return StateVector(vec.x, vec.y, vec.z, 0.0, 0.0, 0.0, time)
+
     raise InvalidBodyError(body)