Do I need to install anything?

No. It runs in any modern browser, free, with no account required.

For First Responders · Nuclear Decay Chain

Nuclear Decay Chain for planetary motion

Built for first responders planning or training for real incidents. Run fast what-if scenarios for response planning and training — no software to install in the field. Simulate planetary motion live below — adjust the inputs and watch it respond, right in your browser.

Radioactive Decay

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Radioactive DecayLive

exponential decay · half-life

Controls

Speed1×

Every half-life, half the remaining atoms decay. After n half-lives, only (1/2)ⁿ is left — the basis of carbon dating and nuclear physics.

Presets

Half-life

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Data Inspector

Half-life4.0

Time0.0

Remaining100.0%

Half-lives0.00

Governing equation

N (t) = N_{0} e^{- λ t}, λ = \frac{ln 2}{4.0} = 0.173

Reading this result: Each half-life removes half of whatever remains, so the curve falls steeply at first and then flattens into a long tail.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Radiometric Dating

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Radiometric DatingLive

reading the atomic clock

Controls

Presets

Remaining fraction

Radioactive isotopes decay at a fixed half-life, so the fraction remaining in a sample is a clock. Measure it and you can read the age: t = half-life × log₂(1/fraction). Carbon-14 dates organic material up to ~50,000 years; uranium-238, with a 4.5-billion-year half-life, dates the oldest rocks and the age of the Earth itself.

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Data Inspector

Half-life5.73e+3 yr

Estimated age5.7 thousand yr

Best fororganic remains < 50k yr

Governing equation

t = t_{1/2} lo g_{2} \frac{1}{0.50} = 1.00 t_{1/2}

Reading this result: About 50% of the Carbon-14 is left, which maps to roughly 1.0 half-lives of elapsed time.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Radiation Dose

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Radiation DoseLive

exposure, distance & time

Your dose vs common references (mSv, log scale)

Your exposure

0.0031

Dental X-ray

0.0050

Chest X-ray

0.10

Annual limit (public)

1.00

CT scan

7.00

Annual limit (worker)

20.00

Controls

Presets

Source activity (MBq)

Distance (m)

Exposure time (hr)

The three ways to reduce radiation dose are time, distance, and shielding. Dose builds with exposure time but falls with the square of distance — doubling your distance quarters the dose. Effective dose in millisieverts lets you compare any exposure to everyday references like a chest X-ray or the annual background dose. Educational estimate only.

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Data Inspector

Dose rate0.0031 mSv/hr

Total dose0.003 mSv

≈ bananas31

Risk levelvery low

Governing equation

D = \frac{Γ A}{r ^{2}} t = \frac{8.4 \times 1 0 ^{- 5} \cdot 37}{1 ^{2}} \cdot 1 = 0.003 mSv

Reading this result: At 1 m for 1 h the estimated dose is 0.003 mSv — about 31 banana-equivalents, a low everyday-scale exposure.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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More with Nuclear Decay Chain

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Frequently asked questions

Is this good for first responders?: Yes — this version of "Nuclear Decay Chain for planetary motion" is framed for first responders planning or training for real incidents. Run fast what-if scenarios for response planning and training — no software to install in the field.
Do I need to install anything?: No. It runs in any modern browser, free, with no account required.