1 point Astronomers recently detected light emitted by a supernova that was originally observed in 1572, just reaching Earth now. This light was reflected off a dust cloud; astronomers call such a reflected light a "light echo" (just like reflected sound is called an echo). How would you expect the spectrum of the light echo to compare to that of the original supernova? The light echo spectrum should look similar to that of the original supernova, with the exception that it will be redder than the original The light echo spectrum should look identical to that of the original supernova with no differences. The light echo spectrum would look completely different to that of the original supernova, with the spectrum featuring additional Balmer, molecular, and 21-cm absorption lines. The light echo spectrum would look completely different to that of the original supernova, with the spectrum featuring additional Balmer, molecular, and 21-cm emission lines. O The light echo spectrum should look similar to that of the original supernova, with the exception that it will be bluer than the original