Kometen jetzt im Sonnensystem

public/solarsystem.php

@@ -7,6 +7,7 @@ session_start();
 
 $loggedIn = isset($_SESSION['user_id']);
 $trackedMinorplanetsForJs = [];
+$trackedCometsForJs = [];
 
 function h(?string $value): string
 {
@@ -71,6 +72,39 @@ function formatMinorplanetDisplayName(array $minorplanet): string
     return $designation !== '' ? $designation : (string) ($minorplanet['packedDesignation'] ?? $minorplanet['desig_packed'] ?? '--');
 }
 
+function formatCometDisplayName(array $comet): string
+{
+    $designation = trim((string) ($comet['designation_and_name'] ?? $comet['designation'] ?? ''));
+    return $designation !== '' ? $designation : (string) ($comet['designation_packed'] ?? $comet['packedDesignation'] ?? '--');
+}
+
+function buildCometPerihelionIso(array $comet): ?string
+{
+    $year = isset($comet['year_of_perihelion']) ? (int) $comet['year_of_perihelion'] : 0;
+    $month = isset($comet['month_of_perihelion']) ? (int) $comet['month_of_perihelion'] : 0;
+    $dayValue = isset($comet['day_of_perihelion']) ? (float) $comet['day_of_perihelion'] : 0.0;
+
+    if ($year <= 0 || $month < 1 || $month > 12 || $dayValue <= 0.0) {
+        return null;
+    }
+
+    $day = (int) floor($dayValue);
+    if ($day < 1 || $day > 31) {
+        return null;
+    }
+
+    $fractionalDay = $dayValue - $day;
+    $seconds = (int) round($fractionalDay * 86400.0);
+
+    try {
+        $date = new DateTimeImmutable(sprintf('%04d-%02d-%02d 00:00:00', $year, $month, $day), new DateTimeZone('UTC'));
+    } catch (Throwable $e) {
+        return null;
+    }
+
+    return $date->modify(sprintf('+%d seconds', $seconds))->format('c');
+}
+
 if ($loggedIn) {
     try {
         $config = require __DIR__ . '/../config/database.php';
@@ -138,8 +172,54 @@ if ($loggedIn) {
                 'isFavorite' => (bool) $minorplanet['is_favorite'],
             ];
         }
+
+        $stmtTrackedComets = $pdo->prepare("
+            SELECT
+                c.`id`,
+                c.`designation_packed`,
+                c.`designation_and_name`,
+                c.`orbit_type`,
+                c.`year_of_perihelion`,
+                c.`month_of_perihelion`,
+                c.`day_of_perihelion`,
+                c.`perihelion_dist_au`,
+                c.`eccentricity`,
+                c.`arg_perihelion_deg`,
+                c.`ascending_node_deg`,
+                c.`inclination_deg`,
+                c.`absolute_magnitude_h`,
+                c.`slope_parameter_g`,
+                auc.`is_favorite`
+            FROM `app_user_comets` auc
+            INNER JOIN `comets_mpc` c
+                ON c.`id` = auc.`comet_id`
+            WHERE auc.`user_id` = :user_id
+            ORDER BY auc.`is_favorite` DESC, c.`year_of_perihelion` ASC, c.`month_of_perihelion` ASC, c.`day_of_perihelion` ASC, c.`designation_and_name` ASC
+        ");
+        $stmtTrackedComets->execute([
+            ':user_id' => (int) $_SESSION['user_id'],
+        ]);
+
+        foreach ($stmtTrackedComets->fetchAll() as $comet) {
+            $trackedCometsForJs[] = [
+                'id' => (int) $comet['id'],
+                'designation' => (string) $comet['designation_and_name'],
+                'packedDesignation' => (string) $comet['designation_packed'],
+                'orbitType' => (string) $comet['orbit_type'],
+                'perihelionIso' => buildCometPerihelionIso($comet),
+                'perihelionDistanceAu' => (float) $comet['perihelion_dist_au'],
+                'eccentricity' => (float) $comet['eccentricity'],
+                'argPerihelionDeg' => (float) $comet['arg_perihelion_deg'],
+                'ascendingNodeDeg' => (float) $comet['ascending_node_deg'],
+                'inclinationDeg' => (float) $comet['inclination_deg'],
+                'absoluteMagnitudeH' => $comet['absolute_magnitude_h'] !== null ? (float) $comet['absolute_magnitude_h'] : null,
+                'photometricIndex' => $comet['slope_parameter_g'] !== null ? (float) $comet['slope_parameter_g'] : null,
+                'isFavorite' => (bool) $comet['is_favorite'],
+            ];
+        }
     } catch (Throwable $e) {
         $trackedMinorplanetsForJs = [];
+        $trackedCometsForJs = [];
     }
 }
 
@@ -219,6 +299,34 @@ $bodyClass = 'solarsystem-page';
                 </div>
             </div>
 
+            <div class="solarsystem-sidebar-block">
+                <div class="solarsystem-label">Komet</div>
+                <div class="solarsystem-input-row">
+                    <details class="solarsystem-multiselect<?= empty($trackedCometsForJs) ? ' is-disabled' : '' ?>" id="solarCometSelectWrap"<?= empty($trackedCometsForJs) ? ' open' : '' ?>>
+                        <summary id="solarCometSelectSummary">
+                            <?= empty($trackedCometsForJs) ? 'Keine Kometen verfuegbar' : 'Kometen auswaehlen' ?>
+                        </summary>
+                        <div class="solarsystem-multiselect-panel" id="solarCometSelectPanel">
+                            <?php if (!empty($trackedCometsForJs)): ?>
+                                <?php foreach ($trackedCometsForJs as $comet): ?>
+                                    <label class="solarsystem-multiselect-option">
+                                        <input
+                                            type="checkbox"
+                                            class="solar-comet-checkbox"
+                                            value="<?= (int) $comet['id'] ?>"
+                                        >
+                                        <span><?= h(formatCometDisplayName($comet)) ?></span>
+                                    </label>
+                                <?php endforeach; ?>
+                            <?php endif; ?>
+                        </div>
+                    </details>
+                </div>
+                <div class="solarsystem-current-date solarsystem-minorplanet-hint" id="solarCometHint">
+                    <?= empty($trackedCometsForJs) ? 'Fuege in den Favoriten Kometen hinzu, um hier ihre Orbits anzuzeigen.' : 'Mehrere Kometen koennen gleichzeitig per Haken eingeblendet werden.' ?>
+                </div>
+            </div>
+
             <div class="solarsystem-sidebar-block">
                 <div class="solarsystem-label">Hinweise</div>
                 <ul class="solarsystem-notes">
@@ -283,6 +391,7 @@ const AstronomyEngine = window.Astronomy;
 const AU_IN_KM = 149597870.7;
 const DISPLAY_SCALE = 34;
 const USER_MINOR_PLANETS = <?= json_encode($trackedMinorplanetsForJs, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES) ?>;
+const USER_COMETS = <?= json_encode($trackedCometsForJs, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES) ?>;
 const JUPITER_MIN_VISIBLE_SIZE = 1.42;
 const MOON_DISPLAY_DISTANCE_MULTIPLIER = 2200;
 
@@ -330,6 +439,9 @@ const infoPanel = document.getElementById('solarInfoPanel');
 const minorPlanetSelectWrap = document.getElementById('solarMinorplanetSelectWrap');
 const minorPlanetSelectSummary = document.getElementById('solarMinorplanetSelectSummary');
 const minorPlanetCheckboxes = Array.from(document.querySelectorAll('.solar-minorplanet-checkbox'));
+const cometSelectWrap = document.getElementById('solarCometSelectWrap');
+const cometSelectSummary = document.getElementById('solarCometSelectSummary');
+const cometCheckboxes = Array.from(document.querySelectorAll('.solar-comet-checkbox'));
 
 if (!AstronomyEngine) {
   overlay.textContent = 'Astronomy Engine konnte nicht geladen werden.';
@@ -352,6 +464,7 @@ let moonMesh = null;
 let moonOrbitLine = null;
 let moonLabelElement = null;
 let minorPlanetObjects = null;
+let cometObjects = null;
 const planetDynamicsCache = new Map();
 
 let showOrbits = true;
@@ -362,6 +475,8 @@ let speedDaysPerSecond = 1;
 let focusedPlanetKey = null;
 let selectedMinorPlanetIds = [];
 let focusedMinorPlanetId = null;
+let selectedCometIds = [];
+let focusedCometId = null;
 let simDate = new Date();
 let lastAnimationTime = performance.now();
 let orbitRefreshCursor = 0;
@@ -470,6 +585,14 @@ function getSelectedMinorPlanetSet() {
   return new Set(selectedMinorPlanetIds);
 }
 
+function getCometMeta(id) {
+  return USER_COMETS.find((comet) => comet.id === Number(id)) || null;
+}
+
+function getSelectedCometSet() {
+  return new Set(selectedCometIds);
+}
+
 const MINOR_PLANET_COLOR_PALETTE = [
   { line: '#ff6b6b', body: '#ff5a5a', emissive: '#d63b3b' },
   { line: '#ff5252', body: '#ff4747', emissive: '#c62828' },
@@ -484,6 +607,20 @@ function getMinorPlanetColor(id) {
   return MINOR_PLANET_COLOR_PALETTE[safeId % MINOR_PLANET_COLOR_PALETTE.length];
 }
 
+const COMET_COLOR_PALETTE = [
+  { line: '#63e6be', body: '#46d9a5', emissive: '#1d7f63' },
+  { line: '#7ad8ff', body: '#58c8f4', emissive: '#1f6e8d' },
+  { line: '#8ce99a', body: '#69db7c', emissive: '#2b8a3e' },
+  { line: '#b2f2bb', body: '#8ce99a', emissive: '#2f9e44' },
+  { line: '#66d9e8', body: '#3bc9db', emissive: '#0b7285' },
+  { line: '#95d5b2', body: '#74c69d', emissive: '#2d6a4f' },
+];
+
+function getCometColor(id) {
+  const safeId = Math.abs(Number(id) || 0);
+  return COMET_COLOR_PALETTE[safeId % COMET_COLOR_PALETTE.length];
+}
+
 function updateMinorPlanetSummary() {
   if (!minorPlanetSelectSummary) {
     return;
@@ -508,6 +645,30 @@ function updateMinorPlanetSummary() {
     : `${selectedNames.length} Kleinplaneten ausgewaehlt`;
 }
 
+function updateCometSummary() {
+  if (!cometSelectSummary) {
+    return;
+  }
+
+  if (cometCheckboxes.length === 0) {
+    cometSelectSummary.textContent = 'Keine Kometen verfuegbar';
+    return;
+  }
+
+  if (selectedCometIds.length === 0) {
+    cometSelectSummary.textContent = 'Kometen auswaehlen';
+    return;
+  }
+
+  const selectedNames = selectedCometIds
+    .map((id) => formatCometName(getCometMeta(id)))
+    .filter((name) => name && name !== '--');
+
+  cometSelectSummary.textContent = selectedNames.length <= 2
+    ? selectedNames.join(', ')
+    : `${selectedNames.length} Kometen ausgewaehlt`;
+}
+
 function formatMinorPlanetName(minorPlanet) {
   if (!minorPlanet) {
     return '--';
@@ -520,6 +681,14 @@ function formatMinorPlanetName(minorPlanet) {
     : designation;
 }
 
+function formatCometName(comet) {
+  if (!comet) {
+    return '--';
+  }
+
+  return String(comet.designation || comet.packedDesignation || '--').trim();
+}
+
 function getHelioPosition(key, date) {
   const body = getPlanetBodyKey(key);
   const vectorEqj = AstronomyEngine.HelioVector(body, date);
@@ -650,6 +819,7 @@ function updateCamera() {
 function clearFocus() {
   focusedPlanetKey = null;
   focusedMinorPlanetId = null;
+  focusedCometId = null;
   cameraTarget.set(0, 0, 0);
   camRadiusTarget = camRadius;
   document.querySelectorAll('.solarsystem-planet-chip').forEach((button) => {
@@ -731,8 +901,51 @@ function updateMinorPlanetInfoPanel(id) {
   document.getElementById('solarInfoType').textContent = `Kleinplanet${minorPlanet.absoluteMagnitudeH !== null ? ` | H ${minorPlanet.absoluteMagnitudeH.toFixed(1)}` : ''}`;
 }
 
+function updateCometInfoPanel(id) {
+  const comet = getCometMeta(id);
+  if (!comet) {
+    infoPanel.hidden = true;
+    return;
+  }
+
+  const position = getCometHelioPosition(comet, simDate);
+  if (!position) {
+    infoPanel.hidden = true;
+    return;
+  }
+
+  const earthPosition = getHelioPosition('Earth', simDate);
+  const earthDistanceAu = Math.hypot(
+    position.x - earthPosition.x,
+    position.y - earthPosition.y,
+    position.z - earthPosition.z
+  );
+  const apparentMagnitude = estimateCometMagnitude(comet, position, earthDistanceAu);
+  const color = getCometColor(id);
+  const semimajorAxisAu = comet.eccentricity < 1 ? comet.perihelionDistanceAu / (1 - comet.eccentricity) : null;
+  const periodDays = semimajorAxisAu !== null ? 365.25 * Math.sqrt(semimajorAxisAu ** 3) : null;
+
+  infoPanel.hidden = false;
+  document.getElementById('solarInfoName').textContent = formatCometName(comet);
+  document.getElementById('solarInfoName').style.color = color.line;
+  document.getElementById('solarInfoDistanceAu').textContent = `${position.r.toFixed(4)} AU`;
+  document.getElementById('solarInfoDistanceKm').textContent = `${(position.r * AU_IN_KM).toFixed(0).replace(/\B(?=(\d{3})+(?!\d))/g, '.')} km`;
+  document.getElementById('solarInfoEarthDistanceAu').textContent = `${earthDistanceAu.toFixed(4)} AU`;
+  document.getElementById('solarInfoEarthDistanceKm').textContent = `${(earthDistanceAu * AU_IN_KM).toFixed(0).replace(/\B(?=(\d{3})+(?!\d))/g, '.')} km`;
+  document.getElementById('solarInfoMagnitude').textContent = apparentMagnitude === null ? '--' : `${apparentMagnitude.toFixed(1)} mag (geschaetzt)`;
+  document.getElementById('solarInfoPeriod').textContent = periodDays === null
+    ? '--'
+    : periodDays >= 365
+      ? `${(periodDays / 365.25).toFixed(2)} Jahre`
+      : `${periodDays.toFixed(2)} Tage`;
+  document.getElementById('solarInfoAxis').textContent = semimajorAxisAu === null ? '--' : `${semimajorAxisAu.toFixed(3)} AU`;
+  document.getElementById('solarInfoType').textContent = `Komet${comet.absoluteMagnitudeH !== null ? ` | H ${comet.absoluteMagnitudeH.toFixed(1)}` : ''}${comet.photometricIndex !== null ? ` | n ${comet.photometricIndex.toFixed(1)}` : ''}`;
+}
+
 function focusPlanet(key) {
   focusedPlanetKey = key;
+  focusedMinorPlanetId = null;
+  focusedCometId = null;
   document.querySelectorAll('.solarsystem-planet-chip').forEach((button) => {
     button.classList.toggle('is-focused', button.dataset.planet === key);
   });
@@ -992,6 +1205,187 @@ function getMinorPlanetHelioPosition(minorPlanet, date) {
   };
 }
 
+function ensureCometObjects() {
+  if (!cometObjects) {
+    cometObjects = new Map();
+  }
+}
+
+function createCometObjects(id) {
+  ensureCometObjects();
+
+  if (cometObjects.has(id)) {
+    return cometObjects.get(id);
+  }
+
+  const color = getCometColor(id);
+  const orbitLine = new THREE.Line(
+    new THREE.BufferGeometry(),
+    new THREE.LineBasicMaterial({
+      color: new THREE.Color(color.line),
+      transparent: true,
+      opacity: 0.85
+    })
+  );
+  orbitLine.visible = false;
+  scene.add(orbitLine);
+
+  const mesh = new THREE.Mesh(
+    new THREE.SphereGeometry(0.5, 24, 24),
+    new THREE.MeshStandardMaterial({
+      color: new THREE.Color(color.body),
+      emissive: new THREE.Color(color.emissive),
+      emissiveIntensity: 0.08,
+      roughness: 0.5,
+      metalness: 0.03,
+    })
+  );
+  mesh.visible = false;
+  mesh.userData.baseScale = 1;
+  mesh.userData.minScaleMultiplier = 1;
+  mesh.userData.cometId = id;
+  scene.add(mesh);
+
+  const labelElement = document.createElement('div');
+  labelElement.className = 'solarsystem-planet-label';
+  labelElement.style.color = color.line;
+  labelElement.hidden = true;
+  labelsLayer.appendChild(labelElement);
+
+  const objects = { orbitLine, mesh, labelElement };
+  cometObjects.set(id, objects);
+  return objects;
+}
+
+function removeCometObjects(id) {
+  if (!cometObjects || !cometObjects.has(id)) {
+    return;
+  }
+
+  const { orbitLine, mesh, labelElement } = cometObjects.get(id);
+  orbitLine.geometry.dispose();
+  orbitLine.material.dispose();
+  scene.remove(orbitLine);
+  mesh.geometry.dispose();
+  mesh.material.dispose();
+  scene.remove(mesh);
+  labelElement.remove();
+  cometObjects.delete(id);
+}
+
+function syncCometObjects() {
+  ensureCometObjects();
+
+  const selectedSet = getSelectedCometSet();
+  selectedCometIds.forEach((id) => {
+    createCometObjects(id);
+  });
+
+  Array.from(cometObjects.keys()).forEach((id) => {
+    if (!selectedSet.has(id)) {
+      removeCometObjects(id);
+    }
+  });
+}
+
+const GAUSSIAN_GRAVITATIONAL_CONSTANT = 0.01720209895;
+const PARABOLIC_ECCENTRICITY_TOLERANCE = 1e-6;
+
+function solveHyperbolicAnomaly(meanAnomaly, eccentricity) {
+  let anomaly = meanAnomaly === 0 ? 0 : Math.asinh(meanAnomaly / eccentricity);
+  for (let i = 0; i < 40; i += 1) {
+    const sinhValue = Math.sinh(anomaly);
+    const coshValue = Math.cosh(anomaly);
+    const delta = (eccentricity * sinhValue - anomaly - meanAnomaly) / (eccentricity * coshValue - 1);
+    anomaly -= delta;
+    if (Math.abs(delta) < 1e-12) {
+      break;
+    }
+  }
+  return anomaly;
+}
+
+function solveParabolicParameter(deltaDays, perihelionDistanceAu) {
+  const scale = GAUSSIAN_GRAVITATIONAL_CONSTANT * deltaDays / Math.sqrt(2 * perihelionDistanceAu ** 3);
+  let parameter = scale;
+  for (let i = 0; i < 40; i += 1) {
+    const delta = (parameter + (parameter ** 3) / 3 - scale) / (1 + parameter ** 2);
+    parameter -= delta;
+    if (Math.abs(delta) < 1e-12) {
+      break;
+    }
+  }
+  return parameter;
+}
+
+function getCometTrueAnomalyAndRadius(deltaDays, perihelionDistanceAu, eccentricity) {
+  if (eccentricity < 1 - PARABOLIC_ECCENTRICITY_TOLERANCE) {
+    const semimajorAxis = perihelionDistanceAu / (1 - eccentricity);
+    const meanMotion = GAUSSIAN_GRAVITATIONAL_CONSTANT / (semimajorAxis ** 1.5);
+    const meanAnomaly = normalizeRadians(meanMotion * deltaDays);
+    const eccentricAnomaly = solveKeplerEquation(meanAnomaly, eccentricity);
+    const radiusAu = semimajorAxis * (1 - eccentricity * Math.cos(eccentricAnomaly));
+    const trueAnomaly = 2 * Math.atan2(
+      Math.sqrt(1 + eccentricity) * Math.sin(eccentricAnomaly / 2),
+      Math.sqrt(1 - eccentricity) * Math.cos(eccentricAnomaly / 2)
+    );
+    return { trueAnomaly, radiusAu };
+  }
+
+  if (eccentricity > 1 + PARABOLIC_ECCENTRICITY_TOLERANCE) {
+    const semimajorAxisAbs = perihelionDistanceAu / (eccentricity - 1);
+    const meanAnomaly = GAUSSIAN_GRAVITATIONAL_CONSTANT * deltaDays / (semimajorAxisAbs ** 1.5);
+    const hyperbolicAnomaly = solveHyperbolicAnomaly(meanAnomaly, eccentricity);
+    const radiusAu = semimajorAxisAbs * (eccentricity * Math.cosh(hyperbolicAnomaly) - 1);
+    const trueAnomaly = 2 * Math.atan2(
+      Math.sqrt(eccentricity + 1) * Math.sinh(hyperbolicAnomaly / 2),
+      Math.sqrt(eccentricity - 1) * Math.cosh(hyperbolicAnomaly / 2)
+    );
+    return { trueAnomaly, radiusAu };
+  }
+
+  const parameter = solveParabolicParameter(deltaDays, perihelionDistanceAu);
+  return {
+    trueAnomaly: 2 * Math.atan(parameter),
+    radiusAu: perihelionDistanceAu * (1 + parameter ** 2),
+  };
+}
+
+function estimateCometMagnitude(comet, helioPosition, earthDistanceAu) {
+  if (!comet || comet.absoluteMagnitudeH === null || comet.photometricIndex === null) {
+    return null;
+  }
+
+  const r = Math.max(helioPosition.r, 1e-9);
+  const delta = Math.max(earthDistanceAu, 1e-9);
+  return comet.absoluteMagnitudeH + (5 * Math.log10(delta)) + (2.5 * comet.photometricIndex * Math.log10(r));
+}
+
+function getCometHelioPosition(comet, date) {
+  if (!comet || !comet.perihelionIso) {
+    return null;
+  }
+
+  const perihelionMs = Date.parse(comet.perihelionIso);
+  if (Number.isNaN(perihelionMs)) {
+    return null;
+  }
+
+  const deltaDays = (date.getTime() - perihelionMs) / 86400000;
+  const orbit = getCometTrueAnomalyAndRadius(deltaDays, comet.perihelionDistanceAu, comet.eccentricity);
+  const inclination = comet.inclinationDeg * Math.PI / 180;
+  const ascendingNode = comet.ascendingNodeDeg * Math.PI / 180;
+  const argPerihelion = comet.argPerihelionDeg * Math.PI / 180;
+  const argumentOfLatitude = orbit.trueAnomaly + argPerihelion;
+
+  return {
+    x: orbit.radiusAu * ((Math.cos(ascendingNode) * Math.cos(argumentOfLatitude)) - (Math.sin(ascendingNode) * Math.sin(argumentOfLatitude) * Math.cos(inclination))),
+    y: orbit.radiusAu * ((Math.sin(ascendingNode) * Math.cos(argumentOfLatitude)) + (Math.cos(ascendingNode) * Math.sin(argumentOfLatitude) * Math.cos(inclination))),
+    z: orbit.radiusAu * (Math.sin(argumentOfLatitude) * Math.sin(inclination)),
+    r: orbit.radiusAu,
+  };
+}
+
 function rebuildMinorPlanetOrbit(id) {
   const minorPlanet = getMinorPlanetMeta(id);
   const objects = createMinorPlanetObjects(id);
@@ -1067,6 +1461,88 @@ function updateMinorPlanetVisual() {
   }
 }
 
+function rebuildCometOrbit(id) {
+  const comet = getCometMeta(id);
+  const objects = createCometObjects(id);
+  if (!comet || !objects) {
+    return;
+  }
+
+  const positions = [];
+  const steps = 720;
+  const beforeDays = comet.eccentricity < 1 ? 3650 : 1200;
+  const afterDays = comet.eccentricity < 1 ? 3650 : 1200;
+
+  for (let step = 0; step <= steps; step += 1) {
+    const fraction = step / steps;
+    const centered = (fraction * 2) - 1;
+    const curved = Math.sign(centered) * Math.pow(Math.abs(centered), 2.2);
+    const offsetDays = curved < 0
+      ? curved * beforeDays
+      : curved * afterDays;
+    const orbitDate = new Date(simDate.getTime() + offsetDays * 86400000);
+    const heliocentric = getCometHelioPosition(comet, orbitDate);
+    if (!heliocentric) {
+      continue;
+    }
+    const display = toDisplayPosition(heliocentric);
+    positions.push(display.x, display.y, display.z);
+  }
+
+  objects.orbitLine.geometry.dispose();
+  objects.orbitLine.geometry = new THREE.BufferGeometry();
+  objects.orbitLine.geometry.setAttribute('position', new THREE.Float32BufferAttribute(positions, 3));
+  objects.orbitLine.visible = showOrbits;
+}
+
+function updateCometVisual() {
+  syncCometObjects();
+
+  if (!cometObjects || cometObjects.size === 0) {
+    if (!focusedPlanetKey && focusedMinorPlanetId === null) {
+      infoPanel.hidden = true;
+    }
+    return;
+  }
+
+  const selectedSet = getSelectedCometSet();
+  cometObjects.forEach((objects, id) => {
+    const comet = getCometMeta(id);
+    const isSelected = selectedSet.has(id);
+    if (!comet || !isSelected) {
+      objects.orbitLine.visible = false;
+      objects.mesh.visible = false;
+      objects.labelElement.hidden = true;
+      return;
+    }
+
+    const heliocentric = getCometHelioPosition(comet, simDate);
+    if (!heliocentric) {
+      objects.orbitLine.visible = false;
+      objects.mesh.visible = false;
+      objects.labelElement.hidden = true;
+      return;
+    }
+
+    const display = toDisplayPosition(heliocentric);
+    objects.mesh.visible = true;
+    objects.mesh.position.copy(display);
+    objects.mesh.rotation.y = (simDate.getTime() / 1000) * 0.0002;
+    objects.orbitLine.visible = showOrbits;
+
+    if (focusedCometId === id) {
+      updateCometInfoPanel(id);
+    }
+  });
+
+  if (focusedCometId !== null && !selectedSet.has(focusedCometId)) {
+    focusedCometId = null;
+    if (!focusedPlanetKey && focusedMinorPlanetId === null) {
+      infoPanel.hidden = true;
+    }
+  }
+}
+
 function createOrbitLine(planet) {
   const periodDays = getPlanetDynamics(planet.key).periodDays ?? 365;
   const steps = planet.key === 'Pluto' ? 300 : 220;
@@ -1271,6 +1747,14 @@ function updateBodyDisplayScales() {
       }
     });
   }
+
+  if (cometObjects) {
+    cometObjects.forEach(({ mesh }) => {
+      if (mesh.visible) {
+        applyMinimumDisplayScale(mesh, 220, 10);
+      }
+    });
+  }
 }
 
 function updateLabels() {
@@ -1312,9 +1796,7 @@ function updateLabels() {
   }
 
   if (!minorPlanetObjects) {
-    return;
+  } else {
-  }
-
     minorPlanetObjects.forEach(({ mesh, labelElement }, id) => {
       const minorPlanet = getMinorPlanetMeta(id);
       labelElement.hidden = !showLabels || !minorPlanet || !mesh.visible;
@@ -1333,6 +1815,30 @@ function updateLabels() {
       labelElement.style.left = `${(projected.x * 0.5 + 0.5) * stageWrap.clientWidth}px`;
       labelElement.style.top = `${(-projected.y * 0.5 + 0.5) * stageWrap.clientHeight}px`;
     });
+  }
+
+  if (!cometObjects) {
+    return;
+  }
+
+  cometObjects.forEach(({ mesh, labelElement }, id) => {
+    const comet = getCometMeta(id);
+    labelElement.hidden = !showLabels || !comet || !mesh.visible;
+    if (labelElement.hidden) {
+      return;
+    }
+
+    const projected = mesh.position.clone().project(camera);
+    if (projected.z > 1) {
+      labelElement.style.opacity = '0';
+      return;
+    }
+
+    labelElement.textContent = formatCometName(comet);
+    labelElement.style.opacity = '1';
+    labelElement.style.left = `${(projected.x * 0.5 + 0.5) * stageWrap.clientWidth}px`;
+    labelElement.style.top = `${(-projected.y * 0.5 + 0.5) * stageWrap.clientHeight}px`;
+  });
 }
 
 function pickPlanet(clientX, clientY) {
@@ -1367,6 +1873,24 @@ function pickPlanet(clientX, clientY) {
     }
   }
 
+  if (cometObjects) {
+    const visibleCometMeshes = Array.from(cometObjects.entries())
+      .filter(([, objects]) => objects.mesh.visible)
+      .map(([id, objects]) => ({ id, mesh: objects.mesh }));
+
+    const cometHits = raycaster.intersectObjects(visibleCometMeshes.map((item) => item.mesh), false);
+    if (cometHits.length > 0) {
+      const hitItem = visibleCometMeshes.find((item) => item.mesh === cometHits[0].object);
+      if (hitItem) {
+        focusedPlanetKey = null;
+        focusedMinorPlanetId = null;
+        focusedCometId = hitItem.id;
+        updateCometInfoPanel(hitItem.id);
+        return;
+      }
+    }
+  }
+
   if (hits.length === 0) {
     clearFocus();
     return;
@@ -1374,6 +1898,7 @@ function pickPlanet(clientX, clientY) {
 
   const hit = meshes.find((item) => item.mesh === hits[0].object);
   if (hit) {
+    focusedCometId = null;
     focusedMinorPlanetId = null;
     focusPlanet(hit.key);
   }
@@ -1468,6 +1993,11 @@ function attachUiHandlers() {
         orbitLine.visible = showOrbits;
       });
     }
+    if (cometObjects) {
+      cometObjects.forEach(({ orbitLine }) => {
+        orbitLine.visible = showOrbits;
+      });
+    }
     if (moonOrbitLine) {
       moonOrbitLine.visible = showOrbits;
     }
@@ -1522,6 +2052,28 @@ function attachUiHandlers() {
       }
     });
   });
+
+  cometCheckboxes.forEach((checkbox) => {
+    checkbox.addEventListener('change', () => {
+      selectedCometIds = cometCheckboxes
+        .filter((input) => input.checked)
+        .map((input) => Number(input.value));
+
+      if (focusedCometId !== null && !selectedCometIds.includes(focusedCometId)) {
+        focusedCometId = null;
+      }
+
+      syncCometObjects();
+      selectedCometIds.forEach((id) => {
+        rebuildCometOrbit(id);
+      });
+      updateCometSummary();
+
+      if (selectedCometIds.length === 0 && !focusedPlanetKey && focusedMinorPlanetId === null && focusedCometId === null) {
+        infoPanel.hidden = true;
+      }
+    });
+  });
 }
 
 function animate() {
@@ -1538,6 +2090,7 @@ function animate() {
   updatePlanetPositions();
   updateMoonVisual();
   updateMinorPlanetVisual();
+  updateCometVisual();
 
   // Aim shadow light from sun toward Saturn
   const saturnMesh = planetMeshes.get('Saturn');
@@ -1567,6 +2120,14 @@ function animate() {
     }
   }
 
+  if (focusedCometId && cometObjects && cometObjects.has(focusedCometId)) {
+    const focusedCometObjects = cometObjects.get(focusedCometId);
+    if (focusedCometObjects.mesh.visible) {
+      cameraTarget.lerp(focusedCometObjects.mesh.position, 0.06);
+      updateCometInfoPanel(focusedCometId);
+    }
+  }
+
   camRadius += (camRadiusTarget - camRadius) * 0.18;
   updateCamera();
   updateBodyDisplayScales();
@@ -1580,6 +2141,11 @@ function animate() {
   if (playing && orbitRefreshCursor % 45 === 0) {
     rebuildMoonOrbitLine();
   }
+  if (playing && orbitRefreshCursor % 60 === 0) {
+    selectedCometIds.forEach((id) => {
+      rebuildCometOrbit(id);
+    });
+  }
   renderer.render(scene, camera);
 }
 
@@ -1605,6 +2171,7 @@ async function initSolarSystem() {
     cameraTarget = new THREE.Vector3(0, 0, 0);
     rotationEqjToEcl = AstronomyEngine.Rotation_EQJ_ECL();
     updateMinorPlanetSummary();
+    updateCometSummary();
 
     const ambientLight = new THREE.AmbientLight(0x334466, 0.8);
     scene.add(ambientLight);