WMO OSCAR | Details for Instrument APT

No JavaScript detected
Usage of this Website will be severly limited without JavaScript. Please enable JavaScript in your Browser.

Instrument: APT

Instrument details

Acronym	APT
Full name	Automatic Picture Transmission
Purpose	Cloud imagery
Short description	Television camera, single VIS cannel, 108° field of view
Background	First installed on TIROS-8, then on Nimbus 1 and 2, then on the operational ESSA series and the initial NOAA satellites. Designed for real-time reception in VHF at inexpensive ground stations, also mobile
Scanning Technique	Snapshot taken in 8 s and then scanned by 800 lines x 800 pixels/line transmitted in real time at the rate of 240 lines/min. Swath ranging from 1200 to 2200 km, depending on the satellite orbital height
Resolution	Ranging from 1.8 to 3 km, depending on the satellite orbital height
Coverage / Cycle	Near-global coverage each day, in daylight
Mass		Power	Data Rate	Analogue: 3.2 kHz base band

Providing Agency	NASA
Instrument Maturity	Flown on operational programme
Utilization Period:	1964 to 1964-09-23
Last update:	2017-03-26

Detailed characteristics

Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

TIROS Operational System (NOAA)
- ESSA-2 (see instrument status) Feb 1966 - Oct 1970
- ESSA-4 (see instrument status) Jan 1967 - May 1968
- ESSA-6 (see instrument status) Nov 1967 - Dec 1969
- ESSA-8 (see instrument status) Dec 1968 - Mar 1976
Nimbus (NASA)
- Nimbus-1 (see instrument status) Aug 1964 - Sep 1964
- Nimbus-2 (see instrument status) May 1966 - Jan 1969
NOAA 3rd generation / Improved TIROS Operational System (NOAA)
- ITOS-1 (TIROS-M) (see instrument status) Jan 1970 - Jun 1971
- NOAA-1 (see instrument status) Dec 1970 - Aug 1971
Television and Infra-Red Observation Satellite (NASA)
- TIROS-8 (see instrument status) Dec 1963 - Jul 1967

Instrument classification

Earth observation instrument
Passive optical radiometer or spectrometer
Moderate resolution optical imager

WIGOS Subcomponents No WIGOS subcomponents have been defined.

Mission objectives

Primary mission objectives

Cloud cover

Secondary mission objectives

Sea-ice cover
Snow cover

Opportunity objectives

Fire fractional cover

Show all Show fewer

Tentative Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers

Variable	Relevance for measuring this variable	Operational limitations	Explanation
Cloud cover	5 - marginal	Daylight only.. Dense cloud only.	VIS channel(s)
Fire fractional cover	5 - marginal	Cloud sensitive.. Coarse spatial resolution.. Daylight only.	VIS channels
Sea-ice cover	5 - marginal	Cloud sensitive.. Daylight only.	VIS channel(s)
Snow cover	5 - marginal	Cloud sensitive.. Daylight only.	VIS channel(s)