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Seeing the Earth through alien eyes: an extraterrestrial view of our planet

Physics World

The lines form a chemical fingerprint that could be used to find “biosignatures” such as oxygen or ozone. This often unpredictable level of electromagnetic radiation can hide an intriguing signal or give false positives for potential biosignatures. Who are you looking at?

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Environmental Perspectives

Environmental Science

Congress toyed with water pollution control since 1948, but 2 years after Earth Day it passed the first comprehensive federal law, ever, to control water pollution, the 1972 Clean Water Act. There remain some problem areas; for example Boston tends to be a non-attainment area for ozone in the summer. Clean Water Act.