Transcript: The direct detection of Earths or even Jupiters is extremely difficult. As seen from afar, a small planet reflects a tiny fraction of the sunlight from the nearby star, and as seen through the Earth’s atmosphere, the light reflected from the planet blurs into the wings of the image...

Transcript: Knowing what the Sun is made of does not tell us how it gets it energy. This was the subject of active debate throughout the nineteenth century. Around the middle of the nineteenth century, the only known energy source for the Sun was chemical energy, such as is obtained by burning...

Transcript: The spectrum of the Sun tells us important things about the atmosphere of the Sun. Two of Kirchhoff’s laws are involved. First, a sufficiently hot gas will emit a thermal spectrum whose radiation peaks in the visible part of the spectrum. This is what we see for sunlight, and the...