6 June 2023
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  • [ 1 June 2023 ] Webb spots vast plume of water vapor spewing from Saturn’s moon Enceladus News
  • [ 26 May 2023 ] Seeing the universe in X-rays, optical and infrared, all at once News
  • [ 15 May 2023 ] A record-setting explosion as a supermassive black hole gorges on gas News
  • [ 13 May 2023 ] Globular cluster mystery may be explained by short-lived ultra-massive suns News
  • [ 12 May 2023 ] Jammed radar boom on Jupiter-bound Juice probe finally freed News
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mean solar day

News

NASA explains why 30 June received an extra ‘leap second’

30 June 2015 Astronomy Now

Although we are unaware of it in our everyday lives, the Earth’s rotation is slowing down, so each mean solar day is about 0.002 seconds longer than the last. NASA explains why Tuesday, 30 June 2015, will have an extra second, or “leap” second, added.

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News Headlines

  • Webb spots vast plume of water vapor spewing from Saturn’s moon Enceladus
    1 June 2023
  • Seeing the universe in X-rays, optical and infrared, all at once
    26 May 2023
  • A record-setting explosion as a supermassive black hole gorges on gas
    15 May 2023
  • Globular cluster mystery may be explained by short-lived ultra-massive suns
    13 May 2023
  • Jammed radar boom on Jupiter-bound Juice probe finally freed
    12 May 2023
  • Home
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