STARLINK-3650

STARLINK-3650 is one of the thousands of mass-produced flat-panel satellites that make up SpaceX's Starlink broadband constellation, catalogued as NORAD object 51982. The catalogue number is the reliable way to refer to it: names are revised and reused, catalogue numbers are permanent.

Which shell it flies in

Its 53.2° inclination puts STARLINK-3650 in Starlink's workhorse 53° shell, the constellation's largest group by some margin. Inclination sets the maximum latitude a satellite ever reaches, so this one sweeps everywhere between roughly 53° north and 53° south on every revolution — a band containing the large majority of the world's population.

That single number is why coverage is not uniform across the globe. Observers near 53° latitude see satellites in this shell climb high overhead; observers much further poleward only ever see them low toward the equator, at a shallow angle that costs both signal strength and visibility.

Its orbital plane

Inclination alone does not say where in space the orbit sits — for that you need the right ascension of the ascending node, which for STARLINK-3650 is 40.3°. Think of inclination as how far the orbital ring is tipped, and RAAN as which way that tip is rotated around the Earth's axis. Satellites sharing a shell share an inclination and differ in RAAN, and each distinct RAAN value is one orbital plane.

Starlink distributes satellites across many planes, evenly spaced around the axis, with a string of satellites strung around each plane. That structure is what makes handover work: because the geometry is designed rather than accidental, there is always a next satellite arriving from a predictable direction at a predictable moment. It is also what the laser crosslink mesh is built on, since each satellite's nearest neighbours in orbit are known in advance.

Speed and orbital period

STARLINK-3650 circles the Earth 15.09 times a day, one full orbit every 95 minutes, travelling at 7.60 km/s — about 27,350 km/h. That speed is not a design choice: at this altitude it is precisely what is required to stay in orbit, and every satellite at the same height moves at effectively the same rate.

Because the Earth keeps turning underneath, each successive orbit crosses the equator about 24° of longitude west of the previous one. That westward walk is why a satellite that passed over you today arrives at a noticeably different time tomorrow, and why pass predictions have to be computed for your specific coordinates rather than read off a repeating timetable.

From the ground the same speed means a pass is brief. STARLINK-3650 crosses from one horizon to the other in a handful of minutes, which is why satellite spotting is an appointment rather than a browse.

Altitude and service life

At roughly 530 km, STARLINK-3650 is inside Starlink's operational band, where satellites spend their working life relaying traffic between user terminals and ground stations. Holding this altitude is not free: even here there is enough residual atmosphere to cause drag, so the satellite has to fire its thruster periodically just to stay put.

Its orbit is very nearly circular: eccentricity 0.00025, with an apogee of 542 km and a perigee of 538 km — a difference of only about 3 km between its highest and lowest points. Communications constellations want circular orbits, because a satellite whose altitude swung widely would deliver inconsistent coverage and latency to everyone beneath it.

It launched in 2022 under international designator 22025AC, deployed as part of a batch on a single Falcon 9. That launch date puts it in the v1.5 generation, with laser crosslinks and the deployable sunshade used for brightness control. Starlink satellites are designed for roughly five years of service, limited mainly by propellant, so at about 4 years old this one is well into the second half of its expected life.

Where it is right now

When this page was generated, STARLINK-3650 was directly above 38.30° S, 7.99° E. It is currently northbound, climbing toward the highest latitude its orbit reaches. The point on the ground beneath a satellite is called its sub-satellite point, and it is the one number on this page that is different every time you load it.

Local solar time at that point was around 21:16 — meaning the ground below was in darkness, though whether it is visible from the ground there depends on whether the satellite itself is still catching sunlight. That distinction is the whole basis of satellite spotting: a satellite is only visible when it is sunlit while the observer beneath it is not.

How current this data is

Everything on this page is computed, not measured. The satellite does not report its position publicly; instead its orbit is described by a two-line element set, and that description is advanced to the current moment with the SGP4 model. This element set has an epoch of 2023-12-28 11:54 UTC, making it about 972 days old. At this age the prediction should be treated with caution: errors grow to tens of kilometres, and any thruster manoeuvre since the epoch is not reflected at all.

Accuracy decays for two reasons the model cannot anticipate. Atmospheric density at this altitude varies with solar activity, so drag is never exactly what was assumed; and Starlink satellites manoeuvre routinely for station-keeping and collision avoidance, which invalidates any element set published beforehand. This site refreshes its data from the public feed every few hours for precisely that reason.

Seeing STARLINK-3650 from the ground

Whether you can see STARLINK-3650 depends first on geography and then on timing. With a maximum latitude of 53°, it can be seen from up to roughly 63° north or south — beyond that it never rises meaningfully above the horizon.

Within that band, the constraint is light. Starlink satellites emit nothing visible; they are seen only by reflected sunlight, which means the satellite has to be sunlit while your own sky is already dark. That happens during twilight — roughly one to two hours after sunset and the same window before sunrise. In the middle of the night STARLINK-3650 passes through Earth's shadow and reflects nothing at all, which is also why a satellite you are watching can fade to nothing partway across the sky.

• Look during twilight — the satellite must be sunlit while your sky is dark
• Expect a steady, unblinking point of light, not a flashing one; aircraft blink
• A pass crosses a large arc of sky in three to six minutes
• A sudden fade partway across means it has entered Earth's shadow