You are correct in that the light originates from the star, but there is some validity in refering to the planets light. As the light passes through or is reflected off the planet's atmosphere, the wavelengths are absorbed or reflected in specific ways corresponding to the chemical makeup of the atmosphere. This changes the spectrum of the light that reaches us.
Although the light is swamped by the light coming directly from the star, the spectra can be compared to the light from the star alone and the difference will be primarily due to the chemical makeup of the planet.
At this point, since nothing has been officially published, its hard to say exactly what has and has not been detected, but this sort of analysis will definately lead to a much better understanding of planet formation.
Slashdot Mirror
One particularly neat thing about Joanoupolis's group is that they also developed photonic band gap simulation software for linux. Check it out.
You are correct in that the light originates from the star, but there is some validity in refering to the planets light. As the light passes through or is reflected off the planet's atmosphere, the wavelengths are absorbed or reflected in specific ways corresponding to the chemical makeup of the atmosphere. This changes the spectrum of the light that reaches us.
Although the light is swamped by the light coming directly from the star, the spectra can be compared to the light from the star alone and the difference will be primarily due to the chemical makeup of the planet.
At this point, since nothing has been officially published, its hard to say exactly what has and has not been detected, but this sort of analysis will definately lead to a much better understanding of planet formation.