<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <link rel="stylesheet" href="{{VENDOR_CDN}}/katex.min.css">
  <script src="{{VENDOR_CDN}}/katex.min.js"></script>
  <script src="{{VENDOR_CDN}}/classace-diagram.js"></script>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    }

    body {
      background: #ffffff;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      justify-content: center;
      min-height: 100%;
    }

    /* Top Formula Row */
    .formula-row {
      display: grid;
      grid-template-columns: 1.1fr auto 1.1fr auto 1.4fr;
      align-items: center;
      gap: 6px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px 12px;
    }

    .f-box {
      text-align: center;
      padding: 6px 4px;
      border-radius: 8px;
      background: #ffffff;
      border: 1px solid #e2e8f0;
      box-shadow: 0 1px 3px rgba(0,0,0,0.03);
    }

    .f-label {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      margin-bottom: 2px;
    }

    .f-val {
      font-size: 15px;
      font-weight: 800;
    }

    .c-speed { color: #0284c7; }
    .c-time { color: #7c3aed; }
    .c-dist { color: #059669; }

    .f-op {
      font-size: 18px;
      font-weight: 700;
      color: #94a3b8;
      text-align: center;
    }

    /* Middle Math Calculation Box */
    .calc-card {
      background: #ffffff;
      border: 1.5px solid #059669;
      border-radius: 12px;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      box-shadow: 0 4px 12px rgba(5, 150, 105, 0.08);
    }

    .calc-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .badge {
      font-size: 11px;
      font-weight: 800;
      padding: 3px 8px;
      border-radius: 6px;
      background: #ecfdf5;
      color: #059669;
      letter-spacing: 0.5px;
    }

    .calc-equation {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: center;
      gap: 6px;
      font-size: 15px;
      font-weight: 700;
      padding: 4px 0;
    }

    .unit-pill {
      padding: 4px 8px;
      border-radius: 6px;
      display: inline-flex;
      align-items: center;
      gap: 3px;
    }

    .pill-speed { background: #e0f2fe; color: #0369a1; }
    .pill-time { background: #f3e8ff; color: #6b21a8; }
    .pill-total { background: #d1fae5; color: #065f46; font-size: 16px; }

    /* Bottom Comparison Bar */
    .compare-card {
      background: #0f172a;
      color: #ffffff;
      border-radius: 12px;
      padding: 12px 14px;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .compare-header {
      display: flex;
      justify-content: space-between;
      align-items: baseline;
    }

    .compare-title {
      font-size: 13px;
      font-weight: 700;
      color: #38bdf8;
    }

    .compare-sub {
      font-size: 13px;
      font-weight: 800;
      color: #facc15;
    }

    .bar-track {
      height: 22px;
      background: #1e293b;
      border-radius: 6px;
      position: relative;
      overflow: hidden;
      display: flex;
      align-items: center;
      border: 1px solid #334155;
    }

    .bar-fill {
      height: 100%;
      width: 100%;
      background: linear-gradient(90deg, #38bdf8 0%, #a855f7 50%, #facc15 100%);
      opacity: 0.9;
    }

    .au-marker {
      position: absolute;
      left: 2px;
      top: 2px;
      bottom: 2px;
      width: 4px;
      background: #ffffff;
      border-radius: 2px;
      box-shadow: 0 0 8px #ffffff;
    }

    .bar-labels {
      display: flex;
      justify-content: space-between;
      font-size: 11px;
      font-weight: 600;
      color: #94a3b8;
    }

    .label-au {
      color: #38bdf8;
      display: flex;
      align-items: center;
      gap: 4px;
    }

    .label-ly {
      color: #facc15;
    }
  </style>
</head>
<body>

  
  <div class="formula-row">
    <div class="f-box">
      <div class="f-label c-speed">Speed (c)</div>
      <div class="f-val c-speed">Light</div>
    </div>
    <div class="f-op">×</div>
    <div class="f-box">
      <div class="f-label c-time">Time (t)</div>
      <div class="f-val c-time">1 Year</div>
    </div>
    <div class="f-op">=</div>
    <div class="f-box">
      <div class="f-label c-dist">Distance (d)</div>
      <div class="f-val c-dist">1 Light-Year</div>
    </div>
  </div>

  
  <div class="calc-card">
    <div class="calc-header">
      <span class="badge">CALCULATION</span>
      <span style="font-size:12px; font-weight:700; color:#64748b;">d = c × t</span>
    </div>
    <div class="calc-equation">
      <span class="unit-pill pill-speed" id="math-speed"></span>
      <span style="color:#94a3b8;">×</span>
      <span class="unit-pill pill-time" id="math-time"></span>
      <span style="color:#94a3b8;">=</span>
      <span class="unit-pill pill-total" id="math-result"></span>
    </div>
  </div>

  
  <div class="compare-card">
    <div class="compare-header">
      <span class="compare-title">Scale Equivalence</span>
      <span class="compare-sub">1 ly = 63,241 AU</span>
    </div>

    <div class="bar-track">
      <div class="bar-fill"></div>
      <div class="au-marker" title="1 AU"></div>
    </div>

    <div class="bar-labels">
      <span class="label-au"><span>▎</span>1 AU (Earth-Sun)</span>
      <span class="label-ly">63,241 AU (1 ly)</span>
    </div>
  </div>

  <script>
    function renderMath() {
      if (window.katex) {
        katex.render("2.998 \\times 10^8\\text{ m/s}", document.getElementById('math-speed'));
        katex.render("3.156 \\times 10^7\\text{ s}", document.getElementById('math-time'));
        katex.render("9.461 \\times 10^{15}\\text{ m}", document.getElementById('math-result'));
      } else {
        document.getElementById('math-speed').innerHTML = "2.998 × 10<sup>8</sup> m/s";
        document.getElementById('math-time').innerHTML = "3.156 × 10<sup>7</sup> s";
        document.getElementById('math-result').innerHTML = "9.461 × 10<sup>15</sup> m";
      }
    }
    window.addEventListener('DOMContentLoaded', renderMath);
    setTimeout(renderMath, 100);
  </script>
</body>
</html>

Astronomical Distance Units: AU, Light-Years, and Parsecs

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      width: 100%;
      height: 100%;
      font-family: system-ui, -apple-system, sans-serif;
      background: #f8fafc;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      padding: 10px 12px;
      user-select: none;
    }

    .toolbar {
      display: flex;
      gap: 8px;
      justify-content: center;
      width: 100%;
      max-width: 480px;
      margin-bottom: 4px;
    }

    .btn {
      flex: 1;
      padding: 6px 10px;
      font-size: 13px;
      font-weight: 600;
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #475569;
      border-radius: 6px;
      cursor: pointer;
      transition: all 0.2s ease;
      text-align: center;
    }

    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
    }

    .btn-jan.active {
      background: #2563eb;
      border-color: #2563eb;
    }

    .btn-jul.active {
      background: #d97706;
      border-color: #d97706;
    }

    .btn-both.active {
      background: #4f46e5;
      border-color: #4f46e5;
    }

    .diagram-svg {
      width: 100%;
      max-width: 520px;
      height: auto;
      flex-grow: 1;
    }

    .sightline-jan {
      stroke: #2563eb;
      stroke-width: 2.5;
      stroke-dasharray: 6 4;
      transition: opacity 0.3s ease;
    }

    .sightline-jul {
      stroke: #d97706;
      stroke-width: 2.5;
      stroke-dasharray: 6 4;
      transition: opacity 0.3s ease;
    }

    .axis-line {
      stroke: #94a3b8;
      stroke-width: 1.5;
      stroke-dasharray: 3 3;
    }

    .baseline {
      stroke: #64748b;
      stroke-width: 2;
    }

    .angle-arc {
      fill: none;
      stroke: #4f46e5;
      stroke-width: 2.5;
      transition: opacity 0.3s ease;
    }

    .star-bg {
      fill: #94a3b8;
    }

    .star-apparent-jan {
      fill: #2563eb;
      transition: opacity 0.3s ease;
    }

    .star-apparent-jul {
      fill: #d97706;
      transition: opacity 0.3s ease;
    }

    .label-text {
      font-size: 12px;
      font-weight: 600;
      fill: #1e2945;
    }

    .dimmed {
      opacity: 0.15;
    }

    .hidden {
      opacity: 0;
    }
  </style>
</head>
<body>

  <div class="toolbar">
    <button class="btn btn-jan" id="btnJan" onclick="setView('jan')">January</button>
    <button class="btn btn-jul" id="btnJul" onclick="setView('jul')">July</button>
    <button class="btn btn-both active" id="btnBoth" onclick="setView('both')">Parallax (Both)</button>
  </div>

  <svg class="diagram-svg" viewBox="0 0 500 420">
    <defs>
      
      <filter id="glow" x="-40%" y="-40%" width="180%" height="180%">
        <feGaussianBlur stdDeviation="3" result="blur" />
        <feMerge>
          <feMergeNode in="blur" />
          <feMergeNode in="SourceGraphic" />
        </feMerge>
      </filter>
    </defs>

    
    <rect x="40" y="24" width="420" height="52" rx="8" fill="#f1f5f9" stroke="#cbd5e1" stroke-width="1.5" />
    <text x="52" y="42" class="label-text" fill="#64748b" font-size="11">Distant Background Stars</text>

    
    <g class="star-bg">
      <circle cx="80" cy="56" r="2.5" />
      <circle cx="120" cy="50" r="3" />
      <circle cx="210" cy="54" r="2.5" />
      <circle cx="290" cy="52" r="2.5" />
      <circle cx="380" cy="56" r="3" />
      <circle cx="420" cy="48" r="2.5" />
    </g>

    
    <line x1="250" y1="365" x2="250" y2="30" class="axis-line" />

    
    <line id="lineJan" x1="140" y1="365" x2="332.5" y2="50" class="sightline-jan" />

    
    <line id="lineJul" x1="360" y1="365" x2="167.5" y2="50" class="sightline-jul" />

    
    <g id="shiftIndicator">
      <line x1="167.5" y1="64" x2="332.5" y2="64" stroke="#4f46e5" stroke-width="1.5" />
      <path d="M 167.5 60 L 167.5 68 M 332.5 60 L 332.5 68" stroke="#4f46e5" stroke-width="1.5" />
      <text x="250" y="74" text-anchor="middle" font-size="10" font-weight="700" fill="#4f46e5">Apparent Shift</text>
    </g>

    
    <circle id="starJanShift" cx="332.5" cy="50" r="6" class="star-apparent-jan" />
    <text id="textJanShift" x="343" y="46" font-size="11" font-weight="700" fill="#2563eb">Jan</text>

    <circle id="starJulShift" cx="167.5" cy="50" r="6" class="star-apparent-jul" />
    <text id="textJulShift" x="157" y="46" text-anchor="end" font-size="11" font-weight="700" fill="#d97706">July</text>

    
    <g id="angleGroup">
      
      <path d="M 250 235 A 50 50 0 0 0 224 228" class="angle-arc" />
      <text x="233" y="252" font-size="13" font-weight="700" fill="#4f46e5">p</text>
      <text x="262" y="235" font-size="11" font-weight="600" fill="#4f46e5">Parallax Angle</text>
    </g>

    
    <g transform="translate(250, 185)" filter="url(#glow)">
      <circle cx="0" cy="0" r="7" fill="#6366f1" />
      <circle cx="0" cy="0" r="3.5" fill="#ffffff" />
    </g>
    <text x="264" y="189" class="label-text">Nearby Star</text>

    
    <ellipse cx="250" cy="365" rx="110" ry="24" fill="none" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="4 4" />

    
    
    <line x1="140" y1="365" x2="250" y2="365" class="baseline" />
    
    <line x1="250" y1="365" x2="360" y2="365" class="baseline" />
    
    <text x="195" y="382" text-anchor="middle" font-size="11" font-weight="700" fill="#475569">1 AU</text>
    <text x="305" y="382" text-anchor="middle" font-size="11" font-weight="700" fill="#475569">1 AU</text>

    
    <circle cx="250" cy="365" r="11" fill="#fbbf24" stroke="#f59e0b" stroke-width="2" />
    <text x="250" y="398" text-anchor="middle" class="label-text">Sun</text>

    
    <g id="earthJan" transform="translate(140, 365)">
      <circle cx="0" cy="0" r="9" fill="#2563eb" stroke="#1d4ed8" stroke-width="2" />
      <circle cx="-2" cy="-2" r="3" fill="#60a5fa" />
      <text x="0" y="24" text-anchor="middle" font-size="12" font-weight="700" fill="#2563eb">Earth (Jan)</text>
    </g>

    
    <g id="earthJul" transform="translate(360, 365)">
      <circle cx="0" cy="0" r="9" fill="#d97706" stroke="#b45309" stroke-width="2" />
      <circle cx="-2" cy="-2" r="3" fill="#fcd34d" />
      <text x="0" y="24" text-anchor="middle" font-size="12" font-weight="700" fill="#d97706">Earth (July)</text>
    </g>
  </svg>

  <script>
    function setView(view) {
      const btnJan = document.getElementById('btnJan');
      const btnJul = document.getElementById('btnJul');
      const btnBoth = document.getElementById('btnBoth');

      const lineJan = document.getElementById('lineJan');
      const lineJul = document.getElementById('lineJul');
      const starJanShift = document.getElementById('starJanShift');
      const textJanShift = document.getElementById('textJanShift');
      const starJulShift = document.getElementById('starJulShift');
      const textJulShift = document.getElementById('textJulShift');
      const angleGroup = document.getElementById('angleGroup');
      const shiftIndicator = document.getElementById('shiftIndicator');
      const earthJan = document.getElementById('earthJan');
      const earthJul = document.getElementById('earthJul');

      btnJan.classList.remove('active');
      btnJul.classList.remove('active');
      btnBoth.classList.remove('active');

      if (view === 'jan') {
        btnJan.classList.add('active');
        lineJan.classList.remove('dimmed', 'hidden');
        lineJul.classList.add('hidden');
        starJanShift.classList.remove('dimmed', 'hidden');
        textJanShift.classList.remove('dimmed', 'hidden');
        starJulShift.classList.add('hidden');
        textJulShift.classList.add('hidden');
        angleGroup.classList.remove('hidden');
        shiftIndicator.classList.add('hidden');
        earthJan.classList.remove('dimmed');
        earthJul.classList.add('dimmed');
      } else if (view === 'jul') {
        btnJul.classList.add('active');
        lineJan.classList.add('hidden');
        lineJul.classList.remove('dimmed', 'hidden');
        starJanShift.classList.add('hidden');
        textJanShift.classList.add('hidden');
        starJulShift.classList.remove('dimmed', 'hidden');
        textJulShift.classList.remove('dimmed', 'hidden');
        angleGroup.classList.add('hidden');
        shiftIndicator.classList.add('hidden');
        earthJan.classList.add('dimmed');
        earthJul.classList.remove('dimmed');
      } else {
        btnBoth.classList.add('active');
        lineJan.classList.remove('dimmed', 'hidden');
        lineJul.classList.remove('dimmed', 'hidden');
        starJanShift.classList.remove('dimmed', 'hidden');
        textJanShift.classList.remove('dimmed', 'hidden');
        starJulShift.classList.remove('dimmed', 'hidden');
        textJulShift.classList.remove('dimmed', 'hidden');
        angleGroup.classList.remove('hidden');
        shiftIndicator.classList.remove('hidden');
        earthJan.classList.remove('dimmed');
        earthJul.classList.remove('dimmed');
      }
    }
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Derivation of 1 Parsec</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #ffffff;
      color: #1e293b;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100vh;
      padding: 10px;
      overflow-x: hidden;
    }

    .container {
      width: 100%;
      max-width: 520px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      flex: 1;
      justify-content: space-between;
    }

    /* Top Step Navigation */
    .nav-bar {
      display: flex;
      gap: 6px;
      width: 100%;
    }

    .step-btn {
      flex: 1;
      padding: 8px 4px;
      font-size: 13px;
      font-weight: 600;
      border-radius: 8px;
      border: 1px solid #cbd5e1;
      background: #f8fafc;
      color: #64748b;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 4px;
      transition: background-color 0.2s, border-color 0.2s, color 0.2s;
    }

    .step-btn:hover {
      background: #f1f5f9;
      color: #334155;
    }

    .step-btn.active {
      background: #eff6ff;
      border-color: #2563eb;
      color: #1d4ed8;
      box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.12);
    }

    /* Visual Geometry Reference */
    .mini-geom {
      width: 100%;
      height: 72px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      padding: 4px 8px;
    }

    .mini-geom svg {
      width: 100%;
      height: 100%;
      max-height: 64px;
    }

    /* Derivation Card Slot */
    .card-slot {
      position: relative;
      min-height: 175px;
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      padding: 12px;
      display: flex;
      flex-direction: column;
      justify-content: center;
      box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
    }

    .step-panel {
      position: absolute;
      inset: 12px;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.22s ease-in-out;
      text-align: center;
    }

    .step-panel.active {
      opacity: 1;
      pointer-events: auto;
    }

    .step-title {
      font-size: 13px;
      font-weight: 700;
      color: #0f172a;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      margin-bottom: 8px;
    }

    .step-desc {
      font-size: 12px;
      color: #64748b;
      margin-bottom: 10px;
    }

    /* Math Formulas (pure CSS/HTML) */
    .math-row {
      display: flex;
      align-items: center;
      justify-content: center;
      flex-wrap: wrap;
      gap: 6px 8px;
      font-family: "Cambria Math", "STIX Two Math", "Times New Roman", serif;
      font-size: 15px;
      color: #1e293b;
      margin: 4px 0;
    }

    .math-row.highlight {
      margin-top: 8px;
      padding: 6px 14px;
      background: #eff6ff;
      border: 1px solid #bfdbfe;
      border-radius: 8px;
      font-weight: 700;
      color: #1d4ed8;
      font-size: 16px;
    }

    .math-var {
      font-style: italic;
      font-family: "Cambria Math", "Times New Roman", serif;
    }

    .frac {
      display: inline-flex;
      flex-direction: column;
      vertical-align: middle;
      text-align: center;
      padding: 0 3px;
      font-size: 0.92em;
      line-height: 1.1;
    }

    .frac .num {
      border-bottom: 1.5px solid currentColor;
      padding-bottom: 2px;
    }

    .frac .den {
      padding-top: 2px;
    }

    .paren-wrap {
      display: inline-flex;
      align-items: center;
      font-size: 1.25em;
      font-weight: 300;
      line-height: 1;
      color: #475569;
    }

    /* Badges */
    .badge-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 6px;
      width: 100%;
      margin-top: 4px;
    }

    .badge {
      background: #f0fdf4;
      border: 1px solid #bbf7d0;
      border-radius: 8px;
      padding: 10px 4px;
      text-align: center;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
    }

    .badge-val {
      font-weight: 700;
      font-size: 13.5px;
      color: #166534;
      font-family: "Cambria Math", "Times New Roman", sans-serif;
    }

    .badge-lbl {
      font-size: 10.5px;
      color: #15803d;
      text-transform: uppercase;
      letter-spacing: 0.4px;
      font-weight: 600;
      margin-top: 3px;
    }

    /* Bottom Navigation Controls */
    .controls {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      padding-top: 2px;
    }

    .nav-arrow {
      background: #f8fafc;
      border: 1px solid #cbd5e1;
      border-radius: 8px;
      padding: 7px 14px;
      font-size: 13px;
      font-weight: 600;
      color: #334155;
      cursor: pointer;
      transition: background-color 0.2s, border-color 0.2s;
    }

    .nav-arrow:hover {
      background: #f1f5f9;
      border-color: #94a3b8;
    }

    .play-btn {
      background: #eff6ff;
      border: 1px solid #bfdbfe;
      border-radius: 8px;
      padding: 7px 14px;
      font-size: 12.5px;
      font-weight: 600;
      color: #1d4ed8;
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 6px;
      transition: background-color 0.2s, border-color 0.2s;
    }

    .play-btn:hover {
      background: #dbeafe;
    }

    @media (max-width: 380px) {
      .math-row {
        font-size: 13.5px;
        gap: 4px 6px;
      }
      .math-row.highlight {
        font-size: 14.5px;
        padding: 5px 10px;
      }
      .badge-val {
        font-size: 12px;
      }
      .badge-lbl {
        font-size: 9.5px;
      }
    }
  </style>
</head>
<body>

  <div class="container">
    
    <div class="nav-bar">
      <button class="step-btn active" data-step="0">1. Angle (<span class="math-var">p</span>)</button>
      <button class="step-btn" data-step="1">2. Distance (<span class="math-var">d</span>)</button>
      <button class="step-btn" data-step="2">3. 1 pc =</button>
    </div>

    
    <div class="mini-geom">
      <svg viewBox="0 0 380 70" preserveAspectRatio="xMidYMid meet">
        
        <line x1="62" y1="48" x2="300" y2="35" stroke="#94a3b8" stroke-width="1.5" stroke-dasharray="3 3"/>
        
        
        <line x1="62" y1="20" x2="62" y2="48" stroke="#0284c7" stroke-width="2.2"/>
        
        
        <path d="M 62 41 L 69 41 L 69 48" fill="none" stroke="#64748b" stroke-width="1"/>

        
        <line x1="62" y1="20" x2="300" y2="35" stroke="#64748b" stroke-width="1.5"/>

        
        <circle cx="62" cy="20" r="5" fill="#0284c7"/>
        <text x="52" y="24" font-size="11" fill="#0369a1" font-weight="700" text-anchor="end">Earth</text>

        <circle cx="62" cy="48" r="5" fill="#eab308"/>
        <text x="52" y="52" font-size="11" fill="#b45309" font-weight="700" text-anchor="end">Sun</text>

        
        <text x="68" y="37" font-size="10" fill="#0284c7" font-weight="700">1 AU</text>

        
        <path d="M 272 33.6 A 28 28 0 0 0 272 36.4" fill="none" stroke="#dc2626" stroke-width="2"/>
        <text x="264" y="31" font-size="11" fill="#dc2626" font-weight="700" text-anchor="end">p = 1″</text>

        
        <circle cx="300" cy="35" r="4.5" fill="#475569"/>
        <text x="310" y="39" font-size="11" fill="#334155" font-weight="700" text-anchor="start">Star (1 pc)</text>
      </svg>
    </div>

    
    <div class="card-slot">
      
      <div class="step-panel active" id="panel-0">
        <div class="step-title">Step 1: Convert Parallax Angle to Radians</div>
        <div class="step-desc">1 arcsecond (1″) is 1/3600 of a degree:</div>
        <div class="math-row">
          <span>1″ = </span>
          <span class="paren-wrap">(</span>
          <span class="frac"><span class="num">1</span><span class="den">3600</span></span>
          <span class="paren-wrap">)</span>°
          <span>×</span>
          <span class="frac"><span class="num">π</span><span class="den">180°</span></span>
        </div>
        <div class="math-row highlight">
          <span class="math-var">p</span>
          <span>= 4.8481 × 10<sup>−6</sup> rad</span>
        </div>
      </div>

      
      <div class="step-panel" id="panel-1">
        <div class="step-title">Step 2: Calculate Parsec Distance</div>
        <div class="step-desc">Small-angle approximation: <span class="math-var">d</span> ≈ 1 AU / <span class="math-var">p</span>(rad)</div>
        <div class="math-row">
          <span class="math-var">d</span>
          <span>=</span>
          <span class="frac">
            <span class="num">1.49598 × 10<sup>11</sup> m</span>
            <span class="den">4.8481 × 10<sup>−6</sup> rad</span>
          </span>
        </div>
        <div class="math-row highlight">
          <span class="math-var">d</span>
          <span>= 3.0857 × 10<sup>16</sup> m</span>
        </div>
      </div>

      
      <div class="step-panel" id="panel-2">
        <div class="step-title" style="color: #166534;">1 Parsec (pc) Equivalent Units</div>
        <div class="step-desc">The distance at which 1 AU subtends an angle of 1 arcsec:</div>
        <div class="badge-grid">
          <div class="badge">
            <div class="badge-val">3.086 × 10¹⁶ m</div>
            <div class="badge-lbl">Meters</div>
          </div>
          <div class="badge">
            <div class="badge-val">3.262 ly</div>
            <div class="badge-lbl">Light-Years</div>
          </div>
          <div class="badge">
            <div class="badge-val">206,265 AU</div>
            <div class="badge-lbl">Astron. Units</div>
          </div>
        </div>
      </div>
    </div>

    
    <div class="controls">
      <button class="nav-arrow" id="prevBtn" aria-label="Previous Step">← Back</button>
      <button class="play-btn" id="playBtn" aria-label="Toggle autoplay"><span id="playIcon">⏸</span> Auto</button>
      <button class="nav-arrow" id="nextBtn" aria-label="Next Step">Next →</button>
    </div>
  </div>

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</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
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  <meta name="aspect-ratio" content="4:3">
  <link rel="stylesheet" href="{{VENDOR_CDN}}/katex.min.css">
  <script src="{{VENDOR_CDN}}/katex.min.js"></script>
  <script src="{{VENDOR_CDN}}/classace-diagram.js"></script>
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    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: #f8fafc;
      color: #1e2945;
      padding: 14px 12px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      min-height: 100%;
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    .top-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 8px;
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    .header-badge {
      font-size: 13px;
      font-weight: 700;
      color: #0284c7;
      background: #e0f2fe;
      padding: 4px 10px;
      border-radius: 999px;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      white-space: nowrap;
    }
    .controls {
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .ctrl-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      color: #334155;
      font-size: 13px;
      font-weight: 600;
      padding: 4px 10px;
      border-radius: 6px;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: background-color 0.2s, border-color 0.2s;
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    .ctrl-btn:hover {
      background: #f1f5f9;
      border-color: #94a3b8;
    }
    .step-dots {
      display: flex;
      gap: 4px;
    }
    .dot-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      color: #64748b;
      font-size: 12px;
      font-weight: 700;
      width: 26px;
      height: 26px;
      border-radius: 50%;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: all 0.25s ease;
    }
    .dot-btn.active {
      background: #0284c7;
      border-color: #0284c7;
      color: #ffffff;
      box-shadow: 0 0 10px rgba(2, 132, 199, 0.4);
    }
    .cards-container {
      display: flex;
      flex-direction: column;
      gap: 10px;
      flex: 1;
      justify-content: space-around;
    }
    .step-card {
      background: #ffffff;
      border-radius: 12px;
      padding: 10px 14px;
      border: 1.5px solid #e2e8f0;
      display: flex;
      flex-direction: column;
      gap: 6px;
      transition: box-shadow 0.3s ease, border-color 0.3s ease, transform 0.2s ease, opacity 0.3s ease;
      cursor: pointer;
      opacity: 0.65;
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    .step-card.active {
      opacity: 1;
      border-color: #0ea5e9;
      box-shadow: 0 0 0 1px #0ea5e9, 0 4px 16px rgba(14, 165, 233, 0.22);
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    .card-meta {
      display: flex;
      align-items: center;
      justify-content: space-between;
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    .step-tag {
      font-size: 11px;
      font-weight: 800;
      letter-spacing: 0.5px;
      text-transform: uppercase;
      padding: 2px 7px;
      border-radius: 4px;
      background: #f1f5f9;
      color: #475569;
    }
    .step-card.active .step-tag {
      background: #e0f2fe;
      color: #0369a1;
    }
    .unit-pill {
      font-size: 11px;
      font-weight: 700;
      color: #64748b;
    }
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      color: #0284c7;
      font-weight: 800;
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      display: flex;
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      min-height: 32px;
      font-size: 15px;
      overflow-x: auto;
      overflow-y: hidden;
      padding-bottom: 2px;
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    .math-row .katex {
      font-size: 1.08em;
    }
  </style>
</head>
<body>

  <div class="top-bar">
    <div class="header-badge">★ Proxima Centauri (p = 0.7685″)</div>
    <div class="controls">
      <div class="step-dots">
        <button class="dot-btn active" data-step="0" aria-label="Step 1">1</button>
        <button class="dot-btn" data-step="1" aria-label="Step 2">2</button>
        <button class="dot-btn" data-step="2" aria-label="Step 3">3</button>
      </div>
      <button class="ctrl-btn" id="playBtn" aria-label="Play/Pause">⏸</button>
    </div>
  </div>

  <div class="cards-container">
    <div class="step-card active" data-index="0">
      <div class="card-meta">
        <span class="step-tag">Step 1</span>
        <span class="unit-pill">Parsecs (pc)</span>
      </div>
      <div class="math-row" id="math1"></div>
    </div>

    <div class="step-card" data-index="1">
      <div class="card-meta">
        <span class="step-tag">Step 2</span>
        <span class="unit-pill">Light-Years (ly)</span>
      </div>
      <div class="math-row" id="math2"></div>
    </div>

    <div class="step-card" data-index="2">
      <div class="card-meta">
        <span class="step-tag">Step 3</span>
        <span class="unit-pill">Astronomical Units (AU)</span>
      </div>
      <div class="math-row" id="math3"></div>
    </div>
  </div>

  <script>
    // Render math formulas with KaTeX
    function renderFormulas() {
      if (typeof katex !== 'undefined') {
        katex.render("d = \\frac{1}{0.7685''} = \\mathbf{1.301\\text{ pc}}", document.getElementById('math1'), { throwOnError: false });
        katex.render("1.301\\text{ pc} \\times 3.262\\frac{\\text{ly}}{\\text{pc}} = \\mathbf{4.244\\text{ ly}}", document.getElementById('math2'), { throwOnError: false });
        katex.render("1.301\\text{ pc} \\times 206{,}265\\frac{\\text{AU}}{\\text{pc}} = \\mathbf{268{,}350\\text{ AU}}", document.getElementById('math3'), { throwOnError: false });
      } else {
        document.getElementById('math1').innerHTML = "<b>d = 1 / 0.7685″ = 1.301 pc</b>";
        document.getElementById('math2').innerHTML = "<b>1.301 pc × 3.262 ly/pc = 4.244 ly</b>";
        document.getElementById('math3').innerHTML = "<b>1.301 pc × 206,265 AU/pc = 268,350 AU</b>";
      }
    }
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    playBtn.addEventListener('click', togglePlay);

    startTimer();
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      width: 100%;
      height: 100%;
      background: #ffffff;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      padding: 12px;
      user-select: none;
      -webkit-user-select: none;
    }

    /* Top AU Callout */
    .callout-box {
      background: #f0f7ff;
      border: 1.5px solid #22b7ff;
      border-radius: 8px;
      padding: 6px 14px;
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 14px;
      font-weight: 600;
      color: #1e2945;
      box-shadow: 0 2px 6px rgba(34, 183, 255, 0.12);
    }
    .callout-box span.val {
      color: #0284c7;
      font-feature-settings: "tnum";
    }

    /* Diagram Area */
    .viewport {
      width: 100%;
      flex: 1;
      min-height: 240px;
      max-height: 320px;
      position: relative;
    }
    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }

    /* Planet selection buttons */
    .controls {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 6px;
      width: 100%;
      margin-top: 4px;
    }
    .btn-planet {
      background: #f8f9fa;
      border: 1px solid #e6e6e6;
      border-radius: 6px;
      padding: 5px 10px;
      font-size: 13px;
      font-weight: 600;
      color: #1e2945;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 5px;
      transition: all 0.2s ease;
    }
    .btn-planet:hover {
      background: #eef2f6;
    }
    .btn-planet.active {
      background: #1e2945;
      color: #ffffff;
      border-color: #1e2945;
    }

    /* Interactive SVG styles */
    .orbit-line {
      stroke: #e2e8f0;
      stroke-width: 1.5;
      stroke-dasharray: 4 3;
      fill: none;
      transition: stroke 0.2s ease, stroke-width 0.2s ease;
    }
    .orbit-line.active {
      stroke: #22b7ff;
      stroke-width: 2.5;
      stroke-dasharray: none;
    }
    .planet-node {
      cursor: pointer;
      transition: transform 0.2s ease;
    }
    .planet-node text {
      font-family: inherit;
      font-size: 12px;
      font-weight: 600;
      fill: #1e2945;
    }
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      font-size: 11px;
      font-weight: 500;
      fill: #64748b;
    }
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      fill: #0284c7;
      font-weight: 700;
    }
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      stroke: #22b7ff;
      stroke-width: 1.5;
      fill: none;
    }
  </style>
</head>
<body>

  
  <div class="callout-box">
    <span>1 AU (Earth-Sun) =</span>
    <span class="val">1.496 × 10¹¹ m</span>
  </div>

  
  <div class="viewport">
    <svg viewBox="0 0 540 280" id="scaleSvg">
      <defs>
        
        <radialGradient id="sunGrad" cx="0%" cy="50%" r="90%">
          <stop offset="0%" stop-color="#fffbeb"/>
          <stop offset="35%" stop-color="#fde047"/>
          <stop offset="70%" stop-color="#f59e0b"/>
          <stop offset="100%" stop-color="#d97706"/>
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        <filter id="glow" x="-20%" y="-20%" width="140%" height="140%">
          <feGaussianBlur stdDeviation="3" result="blur" />
          <feComposite in="SourceGraphic" in2="blur" operator="over" />
        </filter>
      </defs>

      
      <line x1="20" y1="140" x2="520" y2="140" stroke="#f1f5f9" stroke-width="2" />

      
      
      <path id="orbit-mercury" class="orbit-line" d="M -40 20 A 120 120 0 0 1 -40 260" />
      
      <path id="orbit-earth" class="orbit-line active" d="M -40 -30 A 170 170 0 0 1 -40 310" />
      
      <path id="orbit-jupiter" class="orbit-line" d="M -40 -150 A 290 290 0 0 1 -40 430" />
      
      <path id="orbit-neptune" class="orbit-line" d="M -40 -350 A 490 490 0 0 1 -40 630" />

      
      <g id="auBracket">
        <path d="M 0 162 L 0 172 L 130 172 L 130 162" class="baseline-bracket" />
        <line x1="65" y1="172" x2="65" y2="177" class="baseline-bracket" />
        <text x="65" y="191" text-anchor="middle" font-size="11" font-weight="700" fill="#0284c7">1 AU Reference</text>
      </g>

      
      <circle cx="-40" cy="140" r="80" fill="url(#sunGrad)" />
      <circle cx="-40" cy="140" r="84" fill="none" stroke="#f59e0b" stroke-width="2" opacity="0.4" />
      <text x="5" y="144" font-size="13" font-weight="700" fill="#78350f" text-anchor="start">Sun</text>

      
      <g id="node-mercury" class="planet-node" onclick="selectPlanet('mercury')">
        <circle cx="80" cy="140" r="14" fill="#ffffff" stroke="#e6e6e6" stroke-width="1" />
        <circle cx="80" cy="140" r="5" fill="#94a3b8" />
        <text x="80" y="112" text-anchor="middle">Mercury</text>
        <text x="80" y="125" text-anchor="middle" class="sub">0.39 AU</text>
      </g>

      
      <g id="node-earth" class="planet-node active" onclick="selectPlanet('earth')">
        <circle cx="130" cy="140" r="16" fill="#eff6ff" stroke="#22b7ff" stroke-width="1.5" />
        <circle cx="130" cy="140" r="7" fill="#0284c7" />
        <text x="130" y="92" text-anchor="middle">Earth</text>
        <text x="130" y="106" text-anchor="middle" class="sub">1.00 AU</text>
      </g>

      
      <g id="node-jupiter" class="planet-node" onclick="selectPlanet('jupiter')">
        <circle cx="250" cy="140" r="18" fill="#ffffff" stroke="#e6e6e6" stroke-width="1" />
        <circle cx="250" cy="140" r="11" fill="#d97706" />
        <line x1="240" y1="140" x2="260" y2="140" stroke="#b45309" stroke-width="1.5" />
        <text x="250" y="108" text-anchor="middle">Jupiter</text>
        <text x="250" y="122" text-anchor="middle" class="sub">5.20 AU</text>
      </g>

      
      <g id="node-neptune" class="planet-node" onclick="selectPlanet('neptune')">
        <circle cx="450" cy="140" r="16" fill="#ffffff" stroke="#e6e6e6" stroke-width="1" />
        <circle cx="450" cy="140" r="8" fill="#3b82f6" />
        <text x="450" y="108" text-anchor="middle">Neptune</text>
        <text x="450" y="122" text-anchor="middle" class="sub">30.07 AU</text>
      </g>
    </svg>
  </div>

  
  <div class="controls">
    <button class="btn-planet" id="btn-mercury" onclick="selectPlanet('mercury')">Mercury · 0.39 AU</button>
    <button class="btn-planet active" id="btn-earth" onclick="selectPlanet('earth')">Earth · 1.00 AU</button>
    <button class="btn-planet" id="btn-jupiter" onclick="selectPlanet('jupiter')">Jupiter · 5.20 AU</button>
    <button class="btn-planet" id="btn-neptune" onclick="selectPlanet('neptune')">Neptune · 30.07 AU</button>
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Primordial Nucleosynthesis and Light Element Abundances

Evidence for the Big Bang: Redshift and Hubble's Law

Stellar Equilibrium and Hertzsprung-Russell Evolutionary Tracks

Massive Star Collapse and Core-Collapse Supernovae

Neutron Stars, Pulsars, and Degeneracy Pressure

Stellar-Mass Black Holes and Event Horizons

science

Astrophysics, Cosmological Expansion, and Stellar Evolution

Accretion of the Solar Nebula and Planetesimal Formation

Comparative Planetology of the Terrestrial Planets

Gas Giants, Ice Giants, and Dwarf Planets

Remote Sensing of Planetary Surfaces

Planetary Volcanism and Impact Cratering Mechanics

The Giant Impact Hypothesis and the Earth-Moon System

Planetary Differentiation and Core Formation

Crustal Evolution of Terrestrial Bodies

Archean Environments and the Earliest Biosphere

Stromatolites and Banded Iron Formations

The Great Oxidation Event and Paleoproterozoic Red Beds

Planetary Geology and Early Earth Evolution

Zasada superpozycji sił grawitacyjnych w układach wielu ciał

Punkty równowagi sił grawitacyjnych na odcinku między masami

Oddziaływanie grawitacyjne Ziemia-Księżyc i zjawisko pływów

Analiza proporcjonalności w prawie ciążenia — zmiany mas i promieni

Siła ciężkości a siła grawitacji — wpływ ruchu obrotowego Ziemi

Zmienność przyspieszenia ziemskiego w zależności od szerokości geograficznej

Zadania rachunkowe z wektorowego składania sił grawitacji

Grawitacja w skali kosmicznej — struktura wielkoskalowa i ciemna materia

Trening zadań maturalnych z prawa powszechnego ciążenia

Podsumowanie i sprawdzian biegłości — prawo powszechnego ciążenia

Układy grawitacyjne, zjawiska ziemskie i zadania złożone

Słońce, planety grupy ziemskiej oraz planety olbrzymy

Pas główny planetoid, Pas Kuipera i Obłok Oorta — małe ciała Układu Słonecznego

Droga Mleczna — struktura galaktyki spiralnej z poprzeczką, jądro i ramiona spiralne

Położenie Układu Słonecznego w Ramieniu Oriona i odległość od centrum Galaktyki

Ruch obiegowy Słońca wokół jądra Galaktyki i pojęcie roku galaktycznego

Grupa Lokalna Galaktyk — Droga Mleczna, Galaktyka Andromedy i Obłoki Magellana

Budowa Układu Słonecznego i miejsce w Galaktyce

Jednostka astronomiczna (AU) — definicja, wartość w metrach (1,496·10¹¹ m) i zastosowania

Rok świetlny (ly) — definicja, obliczenie ze wzoru d = c·t i wartość ok. 9,46·10¹⁵ m

Przeliczanie odległości między metrami, kilometrami, AU i latami świetlnymi

Paralaksa heliocentryczna i definicja parseka (pc = 3,26 ly)

Drabina odległości kosmicznych — cefeidy, supernowe typu Ia i pomiary odległości

Zadania rachunkowe: czas dotarcia sygnału świetlnego i skale przestrzenne

Skale odległości i jednostki w astronomii

Wielki Wybuch jako początek znanego Wszechświata, przestrzeni i czasu

Kosmologiczne przesunięcie ku czerwieni (redshift z) a ucieczka galaktyk

Prawo Hubble’a-Lemaître’a: zależność v = H₀·d i ucieczka galaktyk

Stała Hubble’a H₀ — jednostka (km/s)/Mpc oraz interpretacja fizyczna tempa ekspansji

Szacowanie wieku Wszechświata jako czasu Hubble’a t = 1/H₀

Kosmiczne mikrofalowe promieniowanie tła (CMBR) jako echo Wielkiego Wybuchu

Supergromady galaktyk i wielkoskalowa struktura Wszechświata — włókna i pustki

Przyszłość i scenariusze ewolucji Wszechświata — Wielki Chłód i Wielkie Rozdarcie

Wielki Wybuch i ewolucja Wszechświata

Druga prędkość kosmiczna (prędkość ucieczki) — wyprowadzenie

Wartość drugiej prędkości kosmicznej dla Ziemi i innych ciał

Trzecia i czwarta prędkość kosmiczna — ucieczka z Układu Słonecznego i Galaktyki

Klasyfikacja orbit ze względu na całkowitą energię mechaniczną

Promień Schwarzschilda i czarne dziury — gdy prędkość ucieczki równa się c

Asysta grawitacyjna — zwiększanie energii sondy kosmicznej kosztem planety

Zadania obliczeniowe z bilansu energetycznego wystrzeliwania satelitów

Złożone zadania z prędkości w dowolnym punkcie toru orbitalnego

Trening zadań maturalnych z energii i prędkości kosmicznych

Podsumowanie i sprawdzian — energia i prędkości kosmiczne

Prędkości kosmiczne i mechanika lotów orbitalnych

Budowa Układu Słonecznego — Słońce, planety skaliste i gazowe olbrzymy

Małe ciała Układu Słonecznego — pas planetoid, pas Kuipera i obłok Oorta

Jednostka astronomiczna (AU) — definicja i zastosowanie w skali planetarnej

Rok świetlny (ly) — definicja, wyprowadzenie z prędkości światła i wartość w metrach

Zjawisko paralaksy heliocentrycznej i trygonometryczny pomiar odległości

Parsek (pc) — definicja, związek z sekundą łuku i przeliczanie na ly oraz metry

Przeliczanie jednostek astronomicznych: AU, ly, pc, kpc, Mpc

Układ Słoneczny i pomiary odległości w astronomii

Struktura Drogi Mlecznej — jądro, ramiona spiralne, dysk i halo

Położenie Układu Słonecznego w Galaktyce i rok galaktyczny

Supermasywna czarna dziura Sagittarius A* w centrum Drogi Mlecznej

Grupa Lokalna Galaktyk — Droga Mleczna, Andromeda (M31) i galaktyki satelitarne

Czas biegu światła w astronomii — patrzenie w przeszłość

Zadania rachunkowe z paralaksy i przeliczania odległości gwiazdowych

Zadania z ruchu obrotowego galaktyk i masy ukrytej

Trening zadań maturalnych z astronomii Układu Słonecznego i galaktyk

Podsumowanie i sprawdzian — skala kosmiczna i struktura galaktyk

Droga Mleczna i wielkoskalowa struktura Wszechświata

Odkrycie ucieczki galaktyk i obserwacje Edwina Hubble’a

Zjawisko Dopplera dla fal świetlnych i przesunięcie ku czerwieni (redshift)

Sformułowanie prawa Hubble’a: v = H₀ · r

Stała Hubble’a H₀ — wartość, jednostki (km/s)/Mpc i wymiar fizyczny 1/s

Obliczanie prędkości ucieczki galaktyk na podstawie odległości

Wyznaczanie odległości do odległych galaktyk z pomiaru redshiftu

Natura rozszerzania się przestrzeni a ruch własny galaktyk

Prawo Hubble’a i kinematyka rozszerzania się Wszechświata

Teoria Wielkiego Wybuchu (Big Bang) — początkowy stan osobliwy i ewolucja

Mikrofalowe promieniowanie tła (CBR) jako świadectwo gorącego początku

Pierwotna nukleosynteza i skład chemiczny wczesnego Wszechświata

Przyspieszona ekspansja Wszechświata i ciemna energia

Zadania rachunkowe ze stosowania prawa Hubble’a i jednostek kosmologicznych

Analiza wykresów Hubble’a — wyznaczanie stałej z nachylenia prostej

Trening zadań maturalnych z kosmologii i prawa Hubble’a

Podsumowanie i sprawdzian — kosmologia i prawo Hubble’a

Model Wielkiego Wybuchu i ewolucja Wszechświata

Narodziny gwiazdy — zapaść grawitacyjna obłoku i protogwiazda

Ciąg główny na diagramie Hertzsprunga-Russella (H-R)

Ewolucja gwiazd o masie Słońca — czerwony olbrzym i biały karzeł

Granica Chandrasekhara — maksymalna masa białego karła

Zaawansowane etapy fuzji w masywnych gwiazdach — struktura cebulowa

Katastrofalna zapaść żelaznego rdzenia i eksplozja supernowej typu II

Supernowe typu Ia jako kosmologiczne świece standardowe

Gwiezdna nukleosynteza — procesy s i r (powstawanie ciężkich pierwiastków)

Ewolucja gwiazd, supernowe i nukleosynteza

Zastosowanie czujników cyfrowych i smartfonów w pomiarach ruchu harmonicznego

Opracowanie raportu laboratoryjnego z analizą niepewności i dyskusją błędów

Analiza zadań maturalnych z doświadczeń z wahadłem i sprężyną

Trening kompleksowy — zadania doświadczalno-rachunkowe z drgań i grawitacji

Podsumowanie i sprawdzian — doświadczalna fizyka drgań

Wielka synteza — grawitacja, astronomia i drgania harmoniczne

Nowoczesne techniki pomiarowe i zadania doświadczalne z drgań

Gwiazdy neutronowe i pulsary — materia zdegenerowana neutronowo

Powstawanie czarnych dziur — horyzont zdarzeń i promień Schwarzschilda

Osobliwość czasoprzestrzenna i dylatacja grawitacyjna wokół czarnej dziury

Obserwacyjne dowody istnienia czarnych dziur — fale grawitacyjne i zdjęcia EHT

Zderzenia gwiazd neutronowych — kilonowe i pochodzenie złota

Zadania maturalne z ewolucji gwiazd i obiektów zwartych

Obiekty zwarte: gwiazdy neutronowe i czarne dziury

OGS.12.ESS.1

OGS.12.ESS.1

Aligned learning resources

Related diagrams