One reason JUUL and vape pens are so popular among teens currently might be that they can be used indoors without attracting unwanted attention or creating a stench, Morean says. On Twitter, teens post about their usage in school.
What is a star's emission spectrum? It is the same as the HR diagram and gives the same information. It is the fingerprint of all of the colors of light emitted by a star. It is a graph of all the pollution given off by a star. It is a graph of the starâs solar flares.
Emission nebulae are usually red, because hydrogen, the most common gas in the universe, most commonly emits red light. Reflection nebulae are clouds of dust that simply reflect the light of a nearby star or stars. Reflection nebulae are usually blue, because blue light scatters more easily.n some nebulae, stars form out of large clouds of gas and dust; once some stars have formed inside the cloud, their light illuminates the cloud, making it visible to us. These star formation regions are sites of emission and reflection nebulae, like the famous Orion Nebula shown in the picture on the right.