You have downloaded the perfect, public domain, image with which to make a new masterpiece but can't seem to DO anything with it.
After a while you notice that GIMP describes it as being a "gray scale" and I can tell you now that that....is the problem.
To DO something to it other than just add more gray stuff, one has to have an "RGB" image.
Presumeably you have the image open in GIMP.
Go to "image" on the toolbar and you will see that the "grayscale" is ticked.
Tick the RGB button and save with another name, also possibly as PNG or BMP or JPEG as you choose, and open that image and you can work with it as you thought you should be able to do.
woodsmoke
After a while you notice that GIMP describes it as being a "gray scale" and I can tell you now that that....is the problem.
To DO something to it other than just add more gray stuff, one has to have an "RGB" image.
Presumeably you have the image open in GIMP.
Go to "image" on the toolbar and you will see that the "grayscale" is ticked.
Tick the RGB button and save with another name, also possibly as PNG or BMP or JPEG as you choose, and open that image and you can work with it as you thought you should be able to do.
woodsmoke