Design sample

A university lab website design sample (English and Korean) made by Dicolab. ORBIT Lab is a fictional lab; the university, people, satellites, papers, projects and posts are not real. Dicolab holds the copyright to this design. Copying or using it without permission may lead to civil and criminal liability. More design samples

Orbit Calculator

Altitude and inclination in; period, passes and ground track out.

Formulas checked Oct 20, 2026

Example calculation 예시 계산 — circular orbit, spherical Earth plus J2, no drag. Good for intuition and coursework, not for operations.

Set the orbit

Sun-synchronous at this altitude: 97.50°

Presets

The address bar keeps your choice (?alt=&inc=), so you can share a result.

Period
95.1 min

T = 2π √(a³ / μ)

Orbital speed
7.60 km/s

v = √(μ / a)

Orbits a day
15.14

86 400 s / T

Track shift per orbit
23.8 ° west

(ω⊕ − Ω̇) · T

Shift at the equator
2,648 km

R⊕ · Δλ

Orbit-plane drift (J2)
+0.99 °/day

Ω̇ = −1.5 n J₂ (R⊕/a)² cos i

Passes over the station
3.2 a day

elevation ≥ 10°, mean of 12 start times

Station footprint radius
1,615 km

λ = acos(R⊕/a · cos ε) − ε

Highest latitude reached
82.5 °

i, or 180° − i

Ground track for the chosen orbit over 24 hours (example calculation)
First orbitNext 24 hoursVisible from the station (elevation ≥ 10°)Example ground station, 36.37° N 127.36° E (fictional rooftop)Simplified coastlines
Constants and assumptions
μ
398,600.4418 km³/s²
R⊕
6,378.137 km (equatorial)
J₂
1.08263 × 10⁻³
ω⊕
7.2921 × 10⁻⁵ rad/s (sidereal)
Sun-synchronous rate
360° per 365.2422 days

Orbits are circular and start at the ascending node. Passes are counted every 30 s over 24 h for 12 starting positions and averaged; a real pass prediction needs the satellite’s current elements (TLE or ephemeris) and drag.