PPolySim OS
For Educators · Mission Planner

Mission Planner for a circadian rhythm

Built for educators teaching it to a class. Drop a live demo into a lecture or assign it as a shareable link — no lab installs. Simulate a circadian rhythm live below — adjust the inputs and watch it respond, right in your browser.

1

Rocket Staging

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Rocket StagingLive

Controls

Presets

The rocket equation grows delta-v only with the logarithm of the mass ratio, so a single stage hauling empty tanks all the way up is hopelessly inefficient. Staging drops dead weight along the way: each stage contributes ve·ln(mass ratio), and their sum easily clears the ~9.4 km/s needed for low Earth orbit.

▶ Run in Python

Data Inspector

Δv per stage4.76 km/s
Total Δv9.52 km/s
Reaches LEO?yes

Governing equation

Reading this result: 2 stages at Isp 350s and mass ratio 4 each sum to 9.5 km/s — past the ~9.4 km/s LEO budget, since every stage adds ve·ln(ratio) after dropping dead weight.

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

2

Escape Velocity

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Escape & Orbital VelocityLive
Escape velocity — Earth
11.19km/s
7.91
orbital km/s
1.00
surface g (× Earth)

Controls

Presets

Escape velocity v = √(2GM/R) is the speed needed to break free of a body's gravity from its surface, ignoring air resistance. Circular orbital velocity is √(GM/R) — a factor of √2 smaller. Both depend only on mass and radius, not on the mass of the escaping object.

▶ Run in Python

Data Inspector

Escape velocity11.19 km/s
Orbital velocity7.91 km/s
Surface gravity9.82 m/s²

Governing equation

Reading this result: Leaving Earth takes 11.2 km/s no matter the spacecraft mass, while a circular orbit needs only 7.9 km/s — smaller by exactly √2 (about 1.41×).

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

3

Orbital Transfer

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Orbital Transfer (Hohmann)Live

Controls

The Hohmann transfer is the fuel-cheapest way between two circular orbits: one burn to enter the transfer ellipse, one to circularize. See the two Δv costs.

Presets

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Data Inspector

Δv burn 11.64
Δv burn 21.34
Total Δv2.99
Transfer time61.3

Governing equation

Reading this result: A moderate transfer (90 → 200, ~2.2×): burn 1 (1.64) enters the ellipse, burn 2 (1.34) circularizes. Bigger ratios cost more total Δv (2.99) and coast longer (61.3).

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

4

Lagrange Points

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Lagrange PointsLive

Controls

Presets

In a two-body system, five points let a small object stay fixed in the rotating frame. L1-L3 sit on the line through the two masses (unstable); L4 and L5 lead and trail the secondary by 60° and are stable for μ below 0.0385 — where Jupiter's Trojan asteroids live. JWST orbits the Sun-Earth L2.

▶ Run in Python

Data Inspector

μ = m₂/(m₁+m₂)0.150
L4/L5 stable?no
Points5

Governing equation

Reading this result: At μ=0.150 the masses are too comparable: even L4 and L5 turn unstable, so every Lagrange point here needs active station-keeping to hold a spacecraft in place.

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

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Frequently asked questions

Is this good for educators?
Yes — this version of "Mission Planner for a circadian rhythm" is framed for educators teaching it to a class. Drop a live demo into a lecture or assign it as a shareable link — no lab installs.
Do I need to install anything?
No. It runs in any modern browser, free, with no account required.