diff --git a/gradle.properties b/gradle.properties
index 16cdd3551..cc44b5b02 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -9,7 +9,7 @@ kotlin.native.ignoreDisabledTargets=true
 org.gradle.configureondemand=true
 org.gradle.jvmargs=-Xmx4096m
 
-toolsVersion=0.14.0-kotlin-1.8.10
+toolsVersion=0.14.1-kotlin-1.8.10
 
 
 org.gradle.parallel=true
diff --git a/kmath-trajectory/src/commonMain/kotlin/space/kscience/kmath/trajectory/tangent.kt b/kmath-trajectory/src/commonMain/kotlin/space/kscience/kmath/trajectory/tangent.kt
index 945b140c2..d3165e162 100644
--- a/kmath-trajectory/src/commonMain/kotlin/space/kscience/kmath/trajectory/tangent.kt
+++ b/kmath-trajectory/src/commonMain/kotlin/space/kscience/kmath/trajectory/tangent.kt
@@ -5,10 +5,7 @@
 
 package space.kscience.kmath.trajectory
 
-import space.kscience.kmath.geometry.Circle2D
-import space.kscience.kmath.geometry.DoubleVector2D
-import space.kscience.kmath.geometry.Euclidean2DSpace
-import space.kscience.kmath.geometry.LineSegment
+import space.kscience.kmath.geometry.*
 import kotlin.math.*
 
 /**
@@ -18,10 +15,14 @@ import kotlin.math.*
 public fun Circle2D.tangentsToCircle(
     other: Circle2D,
 ): Map<DubinsPath.Type, LineSegment<DoubleVector2D>> = with(Euclidean2DSpace) {
+    //return empty map for concentric circles
+    if(center.equalsVector(other.center)) return@tangentsToCircle emptyMap()
+
+    // A line connecting centers
     val line = LineSegment(center, other.center)
-    val d = line.begin.distanceTo(line.end)
+    // Distance between centers
+    val distance = line.begin.distanceTo(line.end)
     val angle1 = atan2(other.center.x - center.x, other.center.y - center.y)
-    var r: Double
     var angle2: Double
     val routes = mapOf(
         DubinsPath.Type.RSR to Pair(radius, other.radius),
@@ -33,30 +34,27 @@ public fun Circle2D.tangentsToCircle(
         for ((route, r1r2) in routes) {
             val r1 = r1r2.first
             val r2 = r1r2.second
-            r = if (r1.sign == r2.sign) {
+            val r = if (r1.sign == r2.sign) {
                 r1.absoluteValue - r2.absoluteValue
             } else {
                 r1.absoluteValue + r2.absoluteValue
             }
-            if (d * d > r * r) {
-                val l = (d * d - r * r).pow(0.5)
-                angle2 = if (r1.absoluteValue > r2.absoluteValue) {
-                    angle1 + r1.sign * atan2(r.absoluteValue, l)
-                } else {
-                    angle1 - r2.sign * atan2(r.absoluteValue, l)
-                }
-                val w = vector(-cos(angle2), sin(angle2))
-                put(
-                    route,
-                    LineSegment(
-                        center + w * r1,
-                        other.center + w * r2
-                    )
+            if (distance <= r) TODO("Intersecting circles are not supported yet")
+            val l = sqrt(distance * distance - r * r)
+            angle2 = if (r1.absoluteValue > r2.absoluteValue) {
+                angle1 + r1.sign * atan2(r.absoluteValue, l)
+            } else {
+                angle1 - r2.sign * atan2(r.absoluteValue, l)
+            }
+            val w = vector(-cos(angle2), sin(angle2))
+            put(
+                route,
+                LineSegment(
+                    center + w * r1,
+                    other.center + w * r2
                 )
-            }
-            else {
-                throw Exception("Circles should not be")
-            }
+            )
+
         }
     }
 }
\ No newline at end of file
diff --git a/kmath-trajectory/src/commonTest/kotlin/space/kscience/kmath/trajectory/TangentTest.kt b/kmath-trajectory/src/commonTest/kotlin/space/kscience/kmath/trajectory/TangentTest.kt
index 3e87b47de..6d4493124 100644
--- a/kmath-trajectory/src/commonTest/kotlin/space/kscience/kmath/trajectory/TangentTest.kt
+++ b/kmath-trajectory/src/commonTest/kotlin/space/kscience/kmath/trajectory/TangentTest.kt
@@ -13,7 +13,6 @@ import space.kscience.kmath.geometry.equalsLine
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertTrue
-import kotlin.test.assertFailsWith
 
 class TangentTest {
     @Test
@@ -56,26 +55,23 @@ class TangentTest {
     }
 
     @Test
-    fun nonExistingTangents() {
-        assertFailsWith<Exception> {
-            val c1 = Circle2D(vector(0.0, 0.0), 10.0)
-            val c2 = Circle2D(vector(0.0, 0.0), 1.0)
-            val segments = c1.tangentsToCircle(c2)
-        }
-        assertFailsWith<Exception> {
-            val c1 = Circle2D(vector(0.0, 0.0), 1.0)
-            val c2 = Circle2D(vector(0.0, 0.0), 10.0)
-            val segments = c1.tangentsToCircle(c2)
-        }
-        assertFailsWith<Exception> {
-            val c1 = Circle2D(vector(0.0, 0.0), 1.0)
-            val c2 = Circle2D(vector(2.0, 0.0), 1.0)
-            val segments = c1.tangentsToCircle(c2)
-        }
-        assertFailsWith<Exception> {
-            val c1 = Circle2D(vector(0.0, 0.0), 1.0)
-            val c2 = Circle2D(vector(0.5, 0.0), 1.0)
-            val segments = c1.tangentsToCircle(c2)
-        }
+    fun concentric(){
+        val c1 = Circle2D(vector(0.0, 0.0), 10.0)
+        val c2 = Circle2D(vector(0.0, 0.0), 1.0)
+        assertEquals(emptyMap(), c1.tangentsToCircle(c2))
     }
+//
+//    @Test
+//    fun nonExistingTangents() {
+//        assertFailsWith<NotImplementedError> {
+//            val c1 = Circle2D(vector(0.0, 0.0), 1.0)
+//            val c2 = Circle2D(vector(2.0, 0.0), 1.0)
+//            c1.tangentsToCircle(c2)
+//        }
+//        assertFailsWith<NotImplementedError> {
+//            val c1 = Circle2D(vector(0.0, 0.0), 1.0)
+//            val c2 = Circle2D(vector(0.5, 0.0), 1.0)
+//            c1.tangentsToCircle(c2)
+//        }
+//    }
 }
\ No newline at end of file
diff --git a/kmath-trajectory/src/commonTest/kotlin/space/kscience/kmath/trajectory/segments/CircleTests.kt b/kmath-trajectory/src/commonTest/kotlin/space/kscience/kmath/trajectory/segments/CircleTests.kt
index 27434b874..c3fca06ec 100644
--- a/kmath-trajectory/src/commonTest/kotlin/space/kscience/kmath/trajectory/segments/CircleTests.kt
+++ b/kmath-trajectory/src/commonTest/kotlin/space/kscience/kmath/trajectory/segments/CircleTests.kt
@@ -19,6 +19,6 @@ class CircleTests {
         val radius = 2.0
         val expectedCircumference = 12.56637
         val circle = Circle2D(center, radius)
-        assertEquals(expectedCircumference, circle.circumference)
+        assertEquals(expectedCircumference, circle.circumference, 1e-4)
     }
 }