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Pulsar Timing Array 3D Explorer vs alternatives
The Pulsar Timing Array 3D Explorer computes the real Hellings-Downs correlation live for any angle in the browser - LIGO's own detector wins for an actual kilohertz gravitational-wave measurement; astrophysics textbooks win for the full mathematical derivation.
| Option | Strength | Access | Trade-off |
|---|---|---|---|
| Pulsar Timing Array 3D (this page) | Live Hellings-Downs correlation for any angle, exact pulsar-pair separation | Free, in browser | Teaching approximation; the other 20 pulsars are illustrative, not a real catalog |
| LIGO (the real detector) | Actual kilohertz gravitational-wave measurement from real black-hole mergers | Public data releases; the observatory itself is not public-access | Different frequency band entirely - cannot show the nanohertz background this page explores |
| Astrophysics textbooks | Full mathematical derivation of the Hellings-Downs formula | Free/paid, education-focused | No interactive 3D scene or live-computed correlation |
Key published figures
| Figure | Value |
|---|---|
| Hellings-Downs correlation at 0 degrees | 0.500 |
| Hellings-Downs correlation at 180 degrees | 0.250 |
| NANOGrav 15-year data set | 68 millisecond pulsars |
| 2023 background amplitude | about 2.4e-15 at 1/year |
Start with the step-by-step guide or when to use. Open the Pulsar Timing Array 3D Explorer.
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