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An attosecond is one quintillionth of a second[1]. To put this in perspective, one attosecond is to one second what one second is to the age of the universe[2][3]. The word attosecond originates from the Danish word for eighteen (atten)[4].


    * 1 attosecond is the time it takes for light to travel the length of three hydrogen atoms.[5]
    * 1 attosecond (1 as) – estimated time it takes for an atomic nucleus to recoil[5]
    * 24 attoseconds – the time taken for an electron to travel from one side of a hydrogen atom to the other[6].
    * 80 attoseconds – the shortest pulses of laser light yet created[7]
    * about 100 attoseconds – record for shortest time interval measured as of February 2004[8]
    * about 200 attoseconds – half-life of beryllium-8, maximum time available for the triple-alpha process for the synthesis of carbon and heavier elements in stars[5].
    * 150 attoseconds is the time it takes for an electron to circle the nucleus of an atom.[2][9]
    * 320 attoseconds – estimated time it takes electrons to hop between atoms[10] ...