Lifetime Workflow

This tutorial configures an orbital lifetime estimate.

Objective

Estimate decay time until a configured re-entry altitude threshold is reached.

Procedure

1. Create a spacecraft with a valid initial orbit.
2. Configure mass, drag area, and Cd carefully.
3. Create a Lifetime Analysis asset from the spacecraft.
4. Use the spacecraft start date.
5. Select DSST-style propagation.
6. Choose atmosphere model and space weather source.
7. Select solar activity scenario: Low, Moderate, High, or comparison.
8. Set maximum duration and output step.
9. Set re-entry altitude, typically not below 180 km for numerical robustness.
10. Run the analysis and inspect altitude, perigee, density, and lifetime summary.

Parameter Guidance

Parameter	Guidance
Output step	Use hours for long studies, not seconds.
Max duration	Set an upper bound larger than expected lifetime.
Re-entry altitude	Use a practical threshold such as 180 to 200 km.
Solar activity	Compare Low/Moderate/High when uncertainty matters.
Drag area and mass	These dominate the ballistic coefficient.

Interpretation

Lifetime outputs are model-dependent. Use them for trade studies and early engineering decisions. For operational re-entry prediction, use validated operational tools and updated space weather data.