GOES 15 Designated Primary X-ray Satellite

October 28, 2010 -- GOES 15 replaced GOES 14 as the Primary SWPC GOES
X-ray Satellite. GOES 14 is being moved into storage. There is no
Secondary SWPC GOES X-ray satellite.

GOES 10 Decommissioning Dec 1, 2009 -- GOES 14 Becomes Primary Satellite for XRS data
No Secondary Satellite for X-rays or Electrons and Protons

November 17, 2009: On Tuesday, 01 December, the GOES 10 satellite will be officially decommissioned. At that time, GOES 14 will replace GOES 10 as the Primary SWPC GOES X-ray Satellite.
[...]
The GOES 10 and GOES 14 XRS instruments have very different electronics and
therefore, there will be some qualitative changes in the appearance of the
data. The main difference will be the level of noise in the data at the
lowest values. When the background levels are low (less than 2E-8 W/m2 or
A2.0), the GOES 10 data looks flat and the steps are very abrupt. At these
low flux levels, the GOES 14 data will be quite noisy. As the x-ray flux
levels rise up above 2E-8, the noise will decrease and the plots will look
very similar to the GOES 10 data.

GOES-10 X-ray Data Returns
GOES-11 Xray Data LOST

February 12, 2008 -- GOES-10 data has resumed and GOES-10 has been designed the SWPC primary GOES Satellite for X-ray data.
GOES-11 Xray Data has become unavailable and is not expected to return.
GOES-11 Data Lists ended on Feb 10, 2008.
GOES-11 Data Lists have been discontinued.

GOES-12 X-ray Lists End
November 27, 2007 -- the GOES-12 X-ray list has been discontinued because the X-ray sensor is not operating.

GOES Primary and Secondary Satellite Change
GOES 11 Primary, GOES 10 Secondary

Due to an anomaly on the GOES 12 X-ray Sensor (XRS) no GOES 12 X-ray data
has been available at SEC since April 12, 2250 UTC. SEC has changed its
Primary and Secondary X-ray satellite designations to GOES 11 Primary and
GOES 10 Secondary.

There may be minor differences between GOES XRS sensors but the differences
should not affect products.

For now GOES X-ray data files will be created for all three GOES satellites,
GOES 11, GOES 10, and GOES 12 in case GOES 12 data is available again.