Science Escape 1 -- The Universe
This is a generally open thread!
During the troubling times of my life, I’ve always found a certain refuge in science and nature. Knowing that whatever idiotic pathway humans invent to tumble down and likely destroy the world, nature will always have the last laugh. I find some comfort in that. So, without further ado, here’s some science to cogitate on!
The Universe
The visible universe is about 14 billion light years in every direction, or about 28 billion light years in diameter. That’s the part we can see, although the actual universe is much larger that that--probably some 91 billion light years in diameter.
The number of galactic supercluster in the visible universe is approximately 10 million.
The number of galactic clusters in the visible universe is approximately 25 billion.
The number of large galaxies (10 billion to several trillion stars) in the visible universe is approximately 350 billion.
The number of dwarf galaxies (less than 10 billion stars) in the visible universe is approximately 7 trillion.
The approximate number of stars in the visible universe is 30 billion trillion.
Intelligent Life in the Universe
One of the greatest questions humans have ever asked is “Are we alone in this universe?” Meaning--of course--are there other intelligent life forms or civilizations out there. Thus far, we have not discovered any. However, if there are none besides us, it does seem, as they say, a great waste of space!
Astrophysicist Frank Drake came up with an equation (Drake’s Equation) that attempts to calculate the probability that intelligent life besides us exists in our Milky Way galaxy. The equation takes as inputs the number of stars that form each year in the galaxy, the total number of stars, the rate of planet formation, the likelihood that planets can sustain life, the likelihood that life arose, etc. Our galaxy has between 100 and 400 billion stars, depending on whose calculation you trust.
If you plug the numbers into the equation, the number of advanced civilizations in our galaxy can be anywhere between 20 at the low end, and 50,000,000 at the high end. Yes, that’s quite a range--but there are a lot of unknowns in there!
I’ve always thought Drake’s equation was too positive, so I’ve taken the low end and divided by 5. I’m estimating there are probably only 4 advanced civilizations in our galaxy--or only 20% of the lowest value of Drake's equation.
Let’s assume for a moment, there are only 4 advanced civilizations (approximately equivalent to humankind or more advanced) in each large galaxy in the universe.
As stated earlier, there are approximately 350 billion large galaxies in the visible universe. Assuming 4 civilizations per large galaxy:
That would mean there are approximately 1 trillion 400 billion advanced civilizations in the visible universe. That discounts dwarf galaxies entirely. That’s how big the universe is!
Wrap your head around that, probably conservative, estimate if you can!
Sources:
https://en.wikipedia.org/wiki/Milky_Way
https://en.wikipedia.org/wiki/Drake_equation
Comments
There is no universe.
No one was around at the big bang to observe its formation to collapse the probability wave. You are your own imagination.
There is no such thing as TMI. It can always be held in reserve for extortion.
I heard a TED talk
this weekend where an astrophysicist postulated that the Big Bang was not the "beginning" it was a Universal Burp that happens all the time. Answering the question what was there before the Bang.
It was a a ghost pepper hors d'oeuvre of course.
Prof: Nancy! I’m going to Greece!
Nancy: And swim the English Channel?
Prof: No. No. To ancient Greece where burning Sapho stood beside the wine dark sea. Wa de do da! Nancy, I’ve invented a time machine!
Firesign Theater
Stop the War!
if there ain't no universe
Ouroboros
How do you know that?
You got it -- your very concept is an Ouroboros, a snake merrily munching its own tail!
And the "observable universe" exists, exactly as much as we do. The classical proof has two steps, from the famous axiom of Rene Descartes:
1. We think, therefore we are.
2. We observe the existence of universal objects and their reliably measurable effects on us and the space we live in. Therefore, they exist as well.
"US govt/military = bad. Russian govt/military = bad. Any politician wanting power = bad. Anyone wielding power = bad." --Shahryar
"All power corrupts absolutely!" -- thanatokephaloides
Whew, that's a relief.
native
Wow
You know, that is strangely comforting.
Marilyn
"Make dirt, not war." eyo
Try this on for size
UFO's Reframing the Debate
https://www.amazon.com/UFOs-Reframing-Debate-Robbie-Graham/dp/1786770237
Sorry, their Caps, not mine.
Sheesh.
Prof: Nancy! I’m going to Greece!
Nancy: And swim the English Channel?
Prof: No. No. To ancient Greece where burning Sapho stood beside the wine dark sea. Wa de do da! Nancy, I’ve invented a time machine!
Firesign Theater
Stop the War!
Sci-Fi Funnies
I'm great at multi-tasking. I can waste time, be unproductive, and procrastinate all at the same time.
I continue to imagine
a moonlit size craft entering Earth orbit, with strange markings on the side translating to "Orkin Galactic".
Neither Russia nor China is our enemy.
Neither Iran nor Venezuela are threatening America.
Cuba is a dead horse, stop beating it.
Wiki-walkin’ “Orkin” led me to termites, which led me to this:
It seems some species of fungi trick termites into keeping them in the nest and caring for them. So is alcohol just a trick by yeast to get humans to cultivate and care for it?
https://blogs.scientificamerican.com/guest-blog/by-looking-carefully-jap...
Just out of curiosity,
are we we living in a large galaxy or a dwarf galaxy?
native
Considering
There is no such thing as TMI. It can always be held in reserve for extortion.
Our galaxy isn't exceptional? Why do you hate America?
Henry,
There is no such thing as TMI. It can always be held in reserve for extortion.
I'm so glad! Laughing is one of my very most favorite things.
Large!
Our Milky Way galaxy is on the large side--as I said, with between 100 billion and 400 billion stars. There was (a rather arbitrary) cut-off at 10 billion stars to differentiate large and dwarf galaxies.
The Large Magellanic Cloud, which is a neighbor galaxy to the Milky Way, is around 10 billion stars--right at the cut-off point. Generally, it is not considered a large galaxy. There is a companion galaxy, The Small Magellanic Cloud, which has around 7 billion stars.
In our Local Group of galaxies, we are the second largest behind the Andromeda galaxy (M31). Andromeda has between 400 billion and 800 billion stars. Some have estimated up to 1 trillion stars there. There is a third large galaxy in our local group, M33, that holds around 60 billion stars. Those are the 3 biggest in our neighborhood.
Thanks for this essay. If any of those four
advanced civilizations are better than ours, I'd really love to meet them. If they are only at our level, ugh. If they are below our level, I'm not worried about them. They'll never find us anyway.
You're Welcome!
Thanks for the note! Yes, if there are only 4 other civilizations in our galaxy, it might be forever until we meet them. Still, the numbers are so, so, so very large, it's almost impossible we are the only intelligent life to emerge. Even if we were some "one off" hapenstance, our galaxy is so large there are likely to be at least 4 more similar one-off happenstances in our galaxy alone.
Trying to imagine 1.4 trillion civilizations out there. We aren't alone, which is the good thing. But, The United Nations for that group would be impossible to comprehend!!!
Things that make you go Hmmmm !
@HenryAWallace
If you were part of a more advanced culture, would you want to come anywhere near the psychopaths running this planet? I once, a very long time ago, wrote a short story about aliens using Earth human culture and ecological treatment as an object lesson in what to avoid. The story as written sucked, lol, but the concept kinda stuck out to me and I can't see why anyone decent from a more civilized would want contact with us...
Psychopathy is not a political position, whether labeled 'conservatism', 'centrism' or 'left'.
A tin labeled 'coffee' may be a can of worms or pathology identified by a lack of empathy/willingness to harm others to achieve personal desires.
Thanks, apenultimate.
The universe sure is a big ol place, innit?
native
This of course calls for Monty Python’s “The Galaxy Song”
[video:https://www.youtube.com/watch?v=hkkjzmuEBbo]
@lotlizard
Thanks for the classic clip! Depressingly accurate, right there at the end, though...
Psychopathy is not a political position, whether labeled 'conservatism', 'centrism' or 'left'.
A tin labeled 'coffee' may be a can of worms or pathology identified by a lack of empathy/willingness to harm others to achieve personal desires.