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Second Hubble repair

Astronauts from the space shuttle Discovery performed repairs and upgrades on Hubble space telescope. They removed old spectrometers and data recorder and installed new. They also replaced several other minor pieces of hardware with upgrades or spares and repaired the thermal insulation of the hull.

Nuclear Fission is explained

Nature journal published a paper by Austrian scientists Lise Meitner and Otto Frisch (they were cousins) on nuclear fission. The reaction itself was discovered by German Otto Hahn a year earlier. Meitner and Frisch found an explanation for it. They named the process by analogy with biological fission of living cells.

Anniversaries of the (in)famous