Best practices to use when determining a satellite's decay time using Satellite Lifetime Tool and HPOP:
- Remember: the Satellite Lifetime tool is best suited for a [long-term] decay time estimate, while HPOP and Astrogator can be used for high fidelity decay time and location prediction.
- Be sure you’re using the same force modeling and drag conditions!
- Satellite Lifetime tool doesn’t have as many properties that can be modified in its force modeling as HPOP, but what it does have, you need to set as close to the HPOP properties you can (i.e. are you using the same Solar Flux files in the Satellite Lifetime Tool and HPOP’s Force Model settings?). See the red boxes in the image below (and attached) for reminders of which properties to compare.
- Remember that HPOP will not propagate below 90km altitude
- Use the Satellite Lifetime Tool first to give you an initial estimate of the decay time
- The fewer orbits per calculation, the more precise the lifetime estimate is, but at the expense of compute time.
- If you want to propagate the satellite forward to analyze the precise re-entry position and time, change the Analysis Time Period to include the Satellite Lifetime Tool’s estimated decay time. Note: you might need to add time to the Satellite Lifetime Tool’s prediction (an hour, a few days, possibly more depending on how imminent the satellite’s decay is).