Why are cepheid variable stars important in our study of the Milky Way? [ad_1] The are used as standard candles to measure distances within our galaxy and nearby galaxies. That is the importance of cepheid variables. What are Cepheid Variables ? In 1784 John Goodricke discovered that the fourth brightest star in the Cepheus constellation […]
Why are cepheid variable stars important in our study of the Milky Way? Read More »
How long is an eon in years? [ad_1] Eon has a number of meanings. In Astronomy an eon refers to 1 billion (##10^9##) years. But it also refers to a very long unspecified period of time or specific geologic stages of . Since this question is posted in Astronomy I will assume that the answer
How long is an eon in years? Read More »
Why do atoms emit or absorb light of specific wavelengths? [ad_1] The electrons in an atom can only occupy certain allowed energy levels. When an electron drops from a higher energy level to a lower one the excess energy is emitted as a photon of light with its wavelength dependent on the change in electron
Why do atoms emit or absorb light of specific wavelengths? Read More »
How is coal formed? [ad_1] Coastal peat swamps build up over time are buried by rising sea levels and eventually get compressed into coal. Coal starts off as vegetative that forms often in coastal regions. Over long periods of time this plant material lives and dies and gradually builds up into thick peat deposits. Sea
How is coal formed? Read More »