A note on Cepheid variables: reproducing the study of the period-luminosity laws

mAnasa-taraMgiNI

In the 13th year of our life, when the skies of our city were still tolerably dark, we observed two stars $latex beta$ Persei (Algol) and $latex delta$ Cephei from our balcony which faced north on every night they were visible. Thus, we reproduced the beginnings of one of the great, but less-appreciated, stories in science that took place in the late 1700s. The story of variable stars, i.e. stars whose brightness changes over time, goes back even earlier. Bullialdus in the late 1600s observed the star $latex o$ Ceti (Mira) for 6 years and established that it varies dramatically in its brightness (magnitude) over a period of 333 days. Presciently he declared that the variability was because of dark regions on the star that periodically presented themselves to the earth even as the sunspots. Newton in his Principia adopted the same explanation for the variability in Mira and subsequently…

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sudhasarathi61

i am not sure what i want in this form of life. NOW I KNOW partially what this existence is. There seems to be more relevance to Bhagavadgita's 66th sloka of 18th chapter.

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