42 detectors
SEVIRI weather camera · 42 detectors
The 42 detectors of SEVIRI, the imager on Europe's four Meteosat Second Generation weather satellites (launched 2002 to 2015): 3 for each of 12 channels, except the High Resolution Visible channel, which has 9. They image the whole Earth disc every 15 minutes.
High over the equator, a European weather satellite called Meteosat watches the whole round face of the Earth with a camera called SEVIRI. It looks in 12 kinds of light, from the light our eyes see to the heat they cannot. Each kind gets 3 tiny detectors, except one sharp visible channel that gets 9. EUMETSAT, which runs the satellites, says it plainly: "The 42 detectors of the twelve channels." Every 15 minutes a new picture of the whole Earth is ready, and forecasters use it to follow clouds and storms. The first one launched in 2002.
What it supports
The 42 is printed by the source, not added up by us. EUMETSAT's technical note on SEVIRI calibration (EUM/OPS-MSG/TEN/03/0064, 17 January 2007, section 2.1, page 6) says SEVIRI is "a compact three-mirror telescope and scan assembly" and that "The 42 detectors of the twelve channels are accommodated in the telescope's focal plane." ESA's 2002 Bulletin article gives the layout: 8 infrared, 2 visible and 1 near-infrared channels with 3 detectors each, and the High Resolution Visible channel with 9, and an overall repeat cycle of 15 minutes. eoPortal prints "a total of 42 detectors." Kepler looked out at stars with 42 CCDs. SEVIRI looks back at Earth with 42 detectors. A coincidence to notice, not a link.
What it does not
Not a number anyone chose; 3 per channel and 9 for the sharp channel came from imaging needs. Not pixels, and not the newer Meteosat Third Generation imager. Not a record we claim. Not astronomy; it looks at Earth, not the sky. Not connected to Kepler. Not Adams.
ExactnessCount
Form42
Unitdetectors
Strengthhard
When2002-08-28
Hung19 October 2026