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A light echo is caused by light reflected off surfaces distant from the source. For example, a light echo is produced when a flash from a supernova is reflected off a cosmic dust cloud. This one, processed by

from a Hubble view, is SN 2016ADJ: buff.ly/37f81Yn

Embedded video

7:30 AM · Jul 10, 2022

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Seeing the speed of light with own eyes!

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Is that a single pulse? I looks like multiple, maybe 3 different pulses? The shape of the light at the end of each pulse appears (to me) to change each time.

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Valentín Karámanliev

@ValentnKarmanl2

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They have made a whole science out of the artificial lighting of the ceiling in our terrarium - astronomy.

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smoke ring

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Great!