Sun-synchronous vs geostationary orbit

Sun-synchronous — a polar orbit that crosses each latitude at the same local time daily (most NASA EO satellites). Geostationary — fixed over one longitude, watching the same hemisphere continuously (weather + TEMPO air quality).

Why it matters

Sun-sync gives global coverage at consistent lighting but only 1–2 looks per day. Geostationary gives constant high-frequency watch of one region but can’t see poles. The orbit dictates what science is possible.

Where you’ll meet it

• Most of the satellites in this Atlas fly sun-synchronous orbits — Terra, Aqua, Suomi NPP, Landsat, and Sentinel-1 all cross at a fixed local time, which is why MODIS scenes always share consistent lighting.
• TEMPO is NASA’s geostationary air-quality instrument, parked over North America to measure pollution hour-by-hour during daylight — something a once-a-day sun-sync pass can’t do.
• The orbit explains the data: sun-sync layers in GIBS update roughly daily per region, while geostationary sources refresh many times an hour over their fixed view.

In plain terms

Sun-sync is a patrol car circling the whole city on a fixed schedule; geostationary is a fixed camera bolted above one neighborhood, always watching.