Heavy element synthesis in the oldest stars and the early Universe

Article Abstract:

The first stars in the Universe were different from the new ones as they are composed entirely of hydrogen and helium, and lacked the heavier elements that determine the formation and evolution of younger stars. The chemical abundances in the oldest surviving stars provide clues about the types or identities of the very first generations of stars in the Galaxy and the Universe.

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The day the solar wind nearly died

Article Abstract:

Issues are presented concerning the factors which contributed to the fall in the density of the solar wind to almost zero on May 11, 1999. The insights which this phenomenon gave to scientists studying the Earths magnetosphere are discussed.

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The age of the Universe

Article Abstract:

Issues are presented concerning the use of radioactive uranium as a dating mechanism to determine the age of the Universe. The revised estimated age of about 12.5-billion years is discussed.

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