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Comment by djmips | Hacker News Reader

> The planet’s rings, in other words, are new phenomena, arising (and potentially even disappearing) in what amounts to a blink of an eye in cosmic terms.

If the universe is ~14 billion years, 400 million is only 1/35th. A person blinks thousands of times a day and maybe 400 million times in their lifetime. I don't really know but is 400 million years really a blink of an eye in cosmic terms?

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A human blink takes about 0.1s. And spends roughly 75 years alive.

Blink/s/min/hr/day/years= 0.1/60/60/24/365/75 = ~4*e-11 ratio of blinks to years alive

Age of universe is 14Byears

14,000,000,000 * 4*e-11 = 0.59 years.

A cosmic blink is about 7months

Thanks that's actually an amazing perspective. Universe, after all - isn't that old if you think about it.

Especially not in relation to how old it is expected to become

That’s one possibility for the Fermi paradox. We might just be the first technological civilization in our neighborhood.

A trillion years from now this place might be packed with them (red dwarf stars, the most common type of star live about two trillion years, unlike our hotter, larger star.)

> Age of universe is 14Byears

It's age now. What will its age be when it is the relative equivalent of a 75yo human? A cosmic blink will be far longer than 7 months.

i don't think there really is such a relative equivalency. the universe according to best current understanding doesn't have anything which resembles human death to demarcate a lifetime. you could say 'heat death' but i dont think thats a strong comparison because, very much unlike human death, its a state which is approached asymptotically; the universe at heat death will look very much like the universe half way to, or even a millionth of the way to

I suppose the closest would be the point at which multicellular/intelligent life becomes impossible, or perhaps when all life becomes impossible. Stellar formation will end in about 100 trillion years, so that seems a good point.

For reference, the Appalachian mountains are older than this.

Sharks are older.

That’s the one I always like to pull out - if prehistoric sharks had telescopes with which to search the night sky, they would have seen Saturn without its rings.

400 My is almost 10% of the age of the Solar System. Definitely not a blink of an eye.

The total lifetime of the universe will be hundreds of trillions of years, which is perhaps a better scale to compare against.

Should read “in what amounts to a quick commute in cosmic terms”.

More like a year in the life of the cosmos.

Maybe people spend about a year of their lives commuting. If you commute an hour a day, every weekday, for 40 years, that’s 10400 hours, compared to the 8760 hours in a year.

“A quick commute” != “The accumulated time of one’s life spent commuting”

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