DMSP 5D-3 F18 (USA 210)

Its mission demonstrates the value of long program continuity: decades of similar orbital observations can support both operations and long-term environmental research.

Its mission demonstrates the value of long program continuity: decades of similar orbital observations can support both operations and long-term environmental research.

Weather spacecraft carry instruments that observe Earth and its atmosphere in visible, infrared, microwave, or other wavelengths. Different orbits provide either repeated regional views or broad global coverage.

• Its mission demonstrates the value of long program continuity: decades of similar orbital observations can support both operations and long-term environmental research.

Its mission demonstrates the value of long program continuity: decades of similar orbital observations can support both operations and long-term environmental research.

The current two-line element set reports approximately 14.1494 revolutions per day. Dividing 1,440 minutes by that value gives an estimated orbital period of 101.8 minutes.

DMSP F18 launched on 18 October 2009 aboard an Atlas V from Vandenberg Air Force Base.

Low Earth orbit is the region closest to Earth used by most crewed spacecraft, many science missions, Earth-observation satellites, and large constellations. Objects move quickly and commonly complete an orbit in roughly 90 to 130 minutes.

LEO can provide detailed Earth views, lower communications delay, and easier access than higher orbits, but it covers less area per spacecraft and is more affected by atmospheric drag.

• Why can infrared instruments observe clouds at night?
• What is the difference between continuous regional coverage and global coverage?

Current identity and orbital elements come from CelesTrak’s public GP data. Calculated orbit values are derived from the current TLE and may change after catalog updates. Mission-history claims are added separately and require authoritative sources.

• CelesTrak NORAD GP Element Sets