Mosaic To New Raster

[RamiAlouta]

Hello
i have on question that may be easy to experts with python.
I am new to the Programing language so i don't have a good background.
Lets start with the inputs
I am working on some NDVI Landsat data in the middle east mainly Lebanon and syria
i downloaded the data from USGS and the first step is to combine the 2 tiles i have into one raster, before i used to perform this through the toolbox but since its really time consuming i decided to learn python and start working through computer language, but due to my little knowledge i am facing a big problem writing the code every time i do it i get an error. so any idea how can i write the for loop so i can process the data i have from 2000 till 2013 without doing it one by one thank you.

[JakeSkinner]

Hi Rami,

Instead of mosaicking all of the rasters to a single raster dataset, I would recommend creating a mosaic dataset.  This will save you time, storage space, and the performance is faster.

[RamiAlouta]

Runtime error  Traceback (most recent call last):   File "<string>", line 3, in <module>   File "c:\program files (x86)\arcgis\desktop10.1\arcpy\arcpy\management.py", line 11613, in MosaicToNewRaster     raise e ExecuteError: ERROR 000157: Input and target dataset should have the same number of band
Any Help Please
i know that both rasters have 1 as a number of band ....