1. The astronomers can determine the chemical composition of stars by analyzing their emission and absorption as the spectra of the sun and the stars exhibits bright and dark lines are these can be caused by the elements absorbing and emitting light at the specific wavelengths,
2. All objects emit radiation as a result of the growing temperature of the charged particles within the objects as the amount of radiation emitted depends on the temperature of the object.
3. The main components of the Milky Way are:
Disk, bulge and halo.
4. The main difference between the atmospheres of Jupiter and Neptune is that Jupiter has methane clouds.
5. The techniques used to find the exosolar planets are based on An analysis of light.