My question might be simple but can someone explain to me the importance of STATION_ID to satellite images?If the sensor is the same(e.g landsat TM) for 2 images but the STATION_ID is different (MLK and XXXO1) is there a problem?
The STATION_ID refers to the satellite ground station. A ground station is used to upload/download data to/from the satellite. You can think of it like a cellphone tower - when the satellite is in range of a ground station it sends the imagery to earth.
Here is a map which shows the location of the ground stations participating in the International Ground Station (IGS) network. It looks like the MLK station you mention is a historical station and is not part of the network currently transmitting/receiving data as part of the Landsat program..
To answer your question - the ground station does not affect the image data.