{"uid":"cap_Ava_Gd7t_skuuERckwqfP","slug":"halowerk-orbit-decay-estimator-23b7f8ff","name":"Halowerk Orbit Decay Estimator","description":"Uses da/dt = -rho×sqrt(mu×a)/ballistic_coefficient for a circular orbit, holds density and ballistic coefficient constant, and linearly projects altitude over a bounded horizon. Real density changes rapidly with altitude and solar activity; the result is not a lifetime prediction or maneuver plan.","url":"https://space.halowerk.com/v1/orbit-decay","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"altitude_km":{"type":"number","maximum":2000,"minimum":100},"horizon_days":{"type":"number","maximum":36500,"minimum":0},"minimum_altitude_km":{"type":"number","maximum":2000,"minimum":0},"atmospheric_density_kg_m3":{"type":"number","maximum":1,"minimum":0,"description":"Caller-supplied density at the modeled altitude."},"ballistic_coefficient_kg_m2":{"type":"number","maximum":1000000000,"minimum":0.000001,"description":"Mass divided by drag coefficient and reference area."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.004","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.004/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.004","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.004","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_qtrP4Oy_UKg2pn95S2ZLY","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.004","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Estimates altitude loss and time-to-reentry for a circular orbit using a simplified drag model with caller-supplied atmospheric density and ballistic coefficient","exampleAgentPrompt":"Estimate the orbit decay for a satellite currently at 450 km altitude with an atmospheric density of 1e-12 kg/m³ and a ballistic coefficient of 50 kg/m², and project how the altitude changes over the next 365 days before it drops below 200 km.","exampleUseCases":[{"title":"CubeSat reentry timeline estimation","prompt":"I have a 3U CubeSat in a circular orbit at 350 km with a ballistic coefficient of 20 kg/m² and atmospheric density of 5e-11 kg/m³. How long before it decays below 150 km? Project it out over 500 days."},{"title":"Space debris altitude forecast","prompt":"There's a debris object at 600 km altitude with a ballistic coefficient of 200 kg/m² and a local density of 1e-13 kg/m³. Can you project its altitude over the next 3000 days and tell me when it drops below 300 km?"},{"title":"Satellite end-of-life planning","prompt":"My satellite is at 800 km in a circular orbit, ballistic coefficient 80 kg/m², atmospheric density 1e-14 kg/m³. Project the altitude decay over 10000 days so I can estimate when it might reach 200 km for end-of-life disposal planning."}],"resultDescription":"Returns a time-series or summary of projected altitude versus time, computed altitude decay rate (da/dt), and estimated time until the minimum altitude threshold is reached, using a simplified constant-density drag model for a circular orbit.","failureModes":["Altitude outside 100–2000 km range returns validation error","Horizon days outside 0–36500 range rejected","Ballistic coefficient of zero or extremely small causes numerical instability","Atmospheric density of zero produces no drag result or error","Model diverges significantly from reality at high altitudes where density varies rapidly with solar activity","Result is not a certified maneuver plan and should not be used for operational decisions"],"whenToPreferThis":"Choose this endpoint when you need a quick, order-of-magnitude estimate of orbital decay for a circular LEO orbit and you already have or can estimate the local atmospheric density and ballistic coefficient. Suitable for feasibility studies, early mission planning, debris tracking approximations, or educational purposes. Not appropriate when high-fidelity propagation with variable density, solar flux (F10.7), or elliptical orbit support is required.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T12:44:36.108Z","isFirstParty":false}