PPolySim OS
Biology & Aerospace Pack · Multi-Solver

Reentry Analysis

Trajectory & heating. This multi-solver chains 2 solvers into a single guided workflow — run each step in order and carry the result forward.

Workflow steps
  1. reentry
  2. standard-atmosphere
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Atmospheric ReentryLive

Controls

Presets

A returning spacecraft sheds nearly all its 7.8 km/s orbital speed as heat in the upper atmosphere. Too shallow an angle and it skips back into space; too steep and the deceleration g-load and heating spike to lethal levels. The ballistic coefficient sets how deep it plunges before the thickening air finally slows it.

▶ Run in Python

Data Inspector

Peak deceleration0.0 g
Entry angle
Survivable?yes

Governing equation

Reading this result: A moderate entry angle keeps peak deceleration within a survivable range while shedding orbital speed as heat.

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

2

Standard Atmosphere

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Standard Atmosphere (ISA)Live

Controls

Presets

The International Standard Atmosphere is the reference model all aircraft and instruments are calibrated against. Temperature falls steadily through the troposphere at 6.5 °C/km, then holds constant in the stratosphere above the tropopause. Pressure and density decay roughly exponentially — at airliner altitude the air is only a quarter as dense as at sea level.

▶ Run in Python

Data Inspector

Temperature-50.0 °C
Pressure26.4 kPa
Density0.413 kg/m³
% sea-level ρ34%

Governing equation

Reading this result: Below the 11 km tropopause, temperature falls at 6.5 °C/km — here it is -50 °C and the air holds 34% of sea-level density.

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

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More in the Biology & Aerospace pack

Frequently asked questions

What is the Reentry Analysis multi-solver?
Reentry Analysis is a guided workflow that chains 2 individual PolySim solvers into one end-to-end analysis, piping each result into the next step.
Is it free to use?
Yes. Every step runs entirely in your browser using real numerics — no install, no account, no cloud cost. Custom or private solver packs are available as a paid service.