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.
Stars are fusion engines, and they are powered primarily by fusing the element hydrogen into the element helium (the first and second most abundant elements in the universe, respectively). This process sometimes goes under the name proton-proton reaction.As stars exhaust their hydrogen fuel and build up a lot of helium, they begin to fuse the helium together to form the element carbon in what is called the triple-alpha process. Links are provided to the relevant Wikipedia articles. The threshold temperature of hydrogen fusion (sometimes called a proton-proton reaction) is on the order of 10,000,000 K to 14,000,000 K or 10 to 14 million degrees Kelvin.