diff --git a/Testbed/Framework/Main.cpp b/Testbed/Framework/Main.cpp
index 937c510748..08ed066030 100644
--- a/Testbed/Framework/Main.cpp
+++ b/Testbed/Framework/Main.cpp
@@ -708,13 +708,16 @@ static void AboutTestUI()
             for (auto& handledKey: handledKeys)
             {
                 const auto keyID = handledKey.first.key;
+                const auto mods = handledKey.first.mods;
                 
                 ImGui::TextUnformatted(GetKeyActionName(handledKey.first.action));
                 ImGui::NextColumn();
                 
                 if (std::isgraph(keyID))
                 {
-                    ImGui::Text("%c", keyID);
+                    const auto shift = mods & GLFW_MOD_SHIFT;
+                    const auto ctrl = mods & GLFW_MOD_CONTROL;
+                    ImGui::Text("%s%s%c", (ctrl? "ctrl-": ""), (shift? "shift-": ""), keyID);
                 }
                 else
                 {
diff --git a/Testbed/Framework/Test.cpp b/Testbed/Framework/Test.cpp
index 3ba7e6d3f2..b9f517ff0b 100644
--- a/Testbed/Framework/Test.cpp
+++ b/Testbed/Framework/Test.cpp
@@ -602,8 +602,8 @@ void Test::LaunchBomb(const Length2& at, const LinearVelocity2 v)
                                 .UseLocation(at).UseLinearVelocity(v));
 
     auto conf = DiskShape::Conf{};
-    conf.vertexRadius = 0.3_m;
-    conf.density = 20_kgpm2;
+    conf.vertexRadius = m_bombRadius;
+    conf.density = m_bombDensity;
     conf.restitution = 0.0f;
     m_bomb->CreateFixture(std::make_shared<DiskShape>(conf));
 }
@@ -1252,7 +1252,7 @@ void Test::KeyboardHandler(KeyID key, KeyAction action, KeyMods mods)
         {
             continue;
         }
-        if (mods & keyActionMods.mods)
+        if (mods != keyActionMods.mods)
         {
             continue;
         }
diff --git a/Testbed/Framework/Test.hpp b/Testbed/Framework/Test.hpp
index cc6817b5b5..24258fe439 100644
--- a/Testbed/Framework/Test.hpp
+++ b/Testbed/Framework/Test.hpp
@@ -320,6 +320,8 @@ class Test : public ContactListener
 
     std::string m_status;
     TextLinePos m_textLine = TextLinePos{30};
+    AreaDensity m_bombDensity = 20_kgpm2;
+    Length m_bombRadius = 0.3_m;
 
 private:
     void DrawStats(const StepConf& stepConf, UiState& ui);
diff --git a/Testbed/Tests/SolarSystem.hpp b/Testbed/Tests/SolarSystem.hpp
index 6449b785b7..e2903a9abc 100644
--- a/Testbed/Tests/SolarSystem.hpp
+++ b/Testbed/Tests/SolarSystem.hpp
@@ -92,7 +92,7 @@ class SolarSystem: public Test
 
         auto conf = Test::Conf{};
         conf.description = os.str();
-        conf.worldDef = WorldDef{}.UseMaxVertexRadius(700000_km);
+        conf.worldDef = WorldDef{}.UseMaxVertexRadius(1e7_km);
         conf.neededSettings = 0;
         conf.neededSettings |= (1u << NeedLinearSlopField);
         conf.neededSettings |= (1u << NeedCameraZoom);
@@ -111,6 +111,8 @@ class SolarSystem: public Test
     
     SolarSystem(): Test(GetTestConf())
     {
+        m_bombRadius = 100_km;
+        m_bombDensity = 2e12_kgpm2;
         m_world.SetGravity(LinearAcceleration2{});
         const auto DynamicBD = BodyDef{}.UseType(BodyType::Dynamic).UseBullet(true);
         for (auto& sso: SolarSystemBodies)
@@ -140,6 +142,26 @@ class SolarSystem: public Test
                        [&](KeyActionMods) {
                            m_focalBody = nullptr;
                        });
+        RegisterForKey(GLFW_KEY_S, GLFW_PRESS, GLFW_MOD_SHIFT,
+                       "Increases bomb size.",
+                       [&](KeyActionMods) {
+                           m_bombRadius *= 2;
+                       });
+        RegisterForKey(GLFW_KEY_S, GLFW_PRESS, 0,
+                       "Decreases bomb size.",
+                       [&](KeyActionMods) {
+                           m_bombRadius /= 2;;
+                       });
+        RegisterForKey(GLFW_KEY_D, GLFW_PRESS, GLFW_MOD_SHIFT,
+                       "Increases bomb density.",
+                       [&](KeyActionMods) {
+                           m_bombDensity *= 2;
+                       });
+        RegisterForKey(GLFW_KEY_D, GLFW_PRESS, 0,
+                       "Decreases bomb density.",
+                       [&](KeyActionMods) {
+                           m_bombDensity /= 2;;
+                       });
     }
     
     void PreStep(const Settings&, Drawer& drawer) override
@@ -161,6 +183,8 @@ class SolarSystem: public Test
         {
             os << "Camera unlocked from following any planet.";
         }
+        os << " 'Bomb' size (radial) is now at " << Real{m_bombRadius/1_km} << "km.";
+        os << " 'Bomb' density (areal) is now at " << Real{m_bombDensity/1_kgpm2} << "kg/m^2.";
         m_status = os.str();
     }