A planet X around a star S

The diagram shows an approximate orbit of a planet X around a star S.


Which of the following statements is false?

(a) The planet moves in an ellipse with the star at one focus.
(b) The planet moves at the same speed at points A and C.
(c) The planet moves fastest at point D.
(d) The potential energy of the planet changes during the orbit.


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Will there be a time when new stars will not form?


Image Credit: ‪‎NASA‬, ESA, the Hubble Heritage Team (STScI/AURA), A. Nota (ESA/STScI), and the Westerlund 2 Science Team

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Excessive twinkling of stars indicates rain or snow

starsExcessive twinkling of stars indicates heavy dews, rain, snow or stormy weather in the near future. Why?

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