How Big is the Universe? How Small Are We in It?
How Big is the Universe? How Small Are We in It?

What our present science understands about the size of the universe already shows us a vast and immense realm—yet it may still only be a tiny drop in one out of a trillion buckets.

On the flip side of the question “how big is the universe?” is the question “how small are humans in it?” It can be dizzying to imagine the scope of the space around us. 

The Epoch Times puts the size of the known universe, estimated to be about 93 billion light years across, into perspective.

How Big is a Star?

The diameter of our sun is about 100 times the diameter of the Earth.

The largest known star, the VY Canis Majoris, is about 2,000 times the size of our sun. It is about 1.8 billion miles in diameter, compared to the sun’s 860,000-mile diameter.

To put that in a more human-scale perspective, if a passenger plane was traveling at its average cruising speed of about 550 mph, it would take about 1,100 years to circle the star once.

(Wikimedia Commons)

 VY Canis Majoris (Wikimedia Commons)

How Many Stars are There in Our Galaxy?

Estimates for the number of stars in the Milky Way range from 100 billion to 300 billion.

Milky Way viewed in the night sky. (Shutterstock)

How Many Galaxies are There in the Known Universe? 

More than 100,000 galaxies have been surveyed to make a 3-D map of the known universe, according to astronomer Karen Masters on Cornell University’s “Ask an Astronomer” website. But the total number of galaxies is unknown, with some estimates around 200 billion. 

Software engineer for Microsoft, Google, and Apple Gayle Laakmann McDowell helps us comprehend how big a billion is. She used an estimate of 100 billion galaxies in the universe to make comparisons.

McDowell wrote in a Quora post, also giving the equations she used: ” If you have just $1, you are much closer to Bill Gates’ net worth ($50 billion) than this galaxy is to the number of total galaxies. Or: if you go on a diet and a lose 10 [pounds], then your weight loss has impacted the world population’s total weight (the sum of everyone’s weight) more than this galaxy impacts the total number of galaxies.”

The Milky Way, a mid-sized galaxy, is about 100,000 light years across. So, it would take a spacecraft 200,000 years to travel to the other side and back if it were to travel at the speed of light. 

How Many Planets are There in the Galaxy?

John Johnson, assistant professor of planetary astronomy at Caltech told the school’s publication: “There’s at least 100 billion planets in the galaxy—just our galaxy.”

“That’s mind-boggling.”


*Lead image of the Earth and space via Shutterstock

  • konspikuous

    Our brain, has to use the extreme limits of our imagination…just to create small steps in ever even beginning to envision, let alone fundamentally grasp, the total volume of it all.

    It is utterly, staggering. Just when you feel like you are getting a hand on it, you realize, no…no you don’t.

    It is a paradoxal, the more we know, the more we realize, we do not know.

    • HeyJude

      Yes, and those that think they (or we) know even a drop of what there is to know are so sadly mistaken. I just want to live long enough to see some of the surprises become known. :-)

      • konspikuous

        I often wonder if we have to escape the limitations of the physics governing our brain to truly grasp what is out there.

        The brain, while a fully functioning quantum machine, is anchored to a very limited conscious.

        That we are cosmic, that our mind itself works on cosmic functions, suggests that there is indeed another plane of tangible interaction with all that is around us. But while encased in skin and bone, I don’t know that reaching out and touching it could ever be possible.

        • konspikuous

          I should say…I’m in no rush to enter the ethereal. I like being corporeal!

          • HeyJude

            See my PS to the other one above…replied to myself instead of you. DOH!!

        • HeyJude

          Are you saying in a roundabout way that you believe there could be dimensional existance and/or parallel universes? I’m one of those people who is open to all things being possible, I would feel very stupid to say without hesitation that there can’t be any such thing. I have no idea what can and can’t be! LOL I wish I understood string theory better… very limited understanding is that there are at least 11 dimensions possible, which is 7 more than we are currently aware of. I see you got your goose cooking over at the Square again…a time out in another dimension might help, I’ll sit with ya! LOL

          • HeyJude

            And btw Kon..I’ve even considered that maybe, just maybe, we all get glimpses of it? Like….what is this deja vu we all experience? We all know it’s real….could we have “traveled” just for a second, without realizing it? How about seeing shadows or ghosts that so many really believe they have seen…could it be that little glimpse of that other dimension that we normally can’t cross to? It sure would explain a bit of the “woooooo woooo” stuff that we experience, and tell ourselves we are imagining.

          • konspikuous

            Are ancients refer to it as, the spirit world. Modern science thinks of it as chemical interactions that axons and dendrites misfire, that result in a long term memory being superimposed upon our visual cortex. Somewhere in between…there’s a truth.

            Our eyes, do not see…it’s out visual processing center that does that. What the eyes are doing is, focusing light and passing it through to the optic nerve. That the center shifts perception to long and short term memory, is why you can close your eyes, and see what it is you’re thinking.

            But, can you see something that your eyes, and visual center, have never seen? That part is tricky as, the brain certainly is capable of creating amalgamations, determining that is though, is not easy. Did I really just see that, or did an errant impulse cause a cascade through my long term facial recognition memory resulting recognizable faces morphed into one that I do not know?

            Another hang up is that, the brain is constantly filling in the blanks with known quantities. When it finds a void, it projects something there to fill it in. It is scary that, a lot of what we think we see, is just illusion. When we perceive colors that absolutely do not exist in the visible spectrum, we’re see the brain’s best interpretation of that color. It has to give it something because, tossing us a blank, or a grey, is unacceptable!

            Back on the spirit plane, because the brain is a quantum interface, the mind is the brain’s quantum ambassador. It is capable of interacting with things that, for all intents and purposes, are not there.

            So, visual center, memory, chemical reaction, electrical impulses, quantum perceptions….all exist. What they ultimately reveal, would take putting our best scientists in the same room with our most learned ancients.

          • HeyJude

            “Somewhere in between….there is the truth.” I like that, and I feel that is where so many answers are. I’m an atheist, so I do reject any notion of a magical one spirit in heaven…creating and directing life only on this planet. Science can whisk away anything otherworldly with the brain chemical reactions and functions, and I reject that as an answer for every instance of strange phenomena that we experience.

            And so yes…somewhere in between there is a lot we don’t know, room for many explanations of the weird and unsettling things that sometimes creep into our realm, or things we get a glimpse of. :-)

          • chenelope

            You assert that you believe in possibility of these magical 11 dimensions, with a further unexplained 7 (7-11, some kind of mystic numerology? There was an episode where Apu visited a 7-11 guru. By the looks of it, you must have asked him more probing questions than Homer). Then in the next breath you reject the possibility of a heaven, or an otherworldly plane, aka dimension. There is no heaven, there is heaven. Huh? No wait, I get it, middle-ground, there is a heaven, but there’s no god there. But that would mean.. aagh, it’s a hell! Get thee behind me Einstein! This quasi-spiritual middle-ground atheism got really dogmatic, really quickly. Is there anyone I can confess to?

          • HeyJude

            Oh my, you have managed to not comprehend a single point in my discussion with Kon. No one except you had any thought to “mystic numerology” or unexplained 7’s being a part. A student of science knows that we live in 4 dimensions, 3 of space and one of time. A basic knowledge of String Theory would further tell you that there are more than that… 11 of them. Pointing out that there are 7 more than we are aware of merely went to the discussion of “what is the nature of the other 7 dimensions”….which Kon had spoken of. Your smug and arrogant reply there shows a reading comprehension difficulty, and perhaps a science deficit? Numerology indeed! LOL
            You also miss on your only other point. I said as an Atheist I do not believe in “One Magical Spirit up in heaven, creating and directing life.” How in the world did you get that I believe in heaven and then I don’t? I stated very clearly that I don’t. You are confusing real dimensional theory with your belief in heaven. There is no quasi spiritual anything to this on my part. “Really quick,” it would be more beneficial for you to read, rather than confess anything. Clearly my direction was to explain “ghost sightings” as something other than heaven, but you were too eager to inject your religion in a science discussion, and came up flat with imagined numerology and such. Next time you come to a discussion, perhaps you should read what was actually written.

          • rg9rts

            Did you ever read “The Naked Ape” by Desmond Morris. He handled the religion business very nicely. Did a good job. Give me the fork and I’ll help you.(muck). LOL

          • HeyJude

            LOL Here’s your fork…see you on the main?? Going there…

          • chenelope

            Seeing as how the concept of irony isn’t defined by quantum mechanical theory, you can be forgiven for also not perceiving its existence. On second thoughts, perhaps “forgiven” is the wrong word.. allowing for a statistical margin of error will resonate better with you, perhaps. Actually, Professor Frink gives the Simpsons a scientific edge, and you can watch it with the mute button at the ready for when Ned Flanders and Reverend Lovejoy appear. An opening scene “couch gag” reveals a multi-layered cartoon universe that has shaken all 4 corners of this flat earth.

            Technically speaking though, if you’re putting your eggs in the “real” dimensional theory basket, it’s no different from religious people’s “postulation”, or “belief”, in otherworldly realms, aka heavens. So you can decide to affirm your faith in the alter of science which now postulates the existence of other dimensions, while at the same time endorsing the age-old religious belief in heavens (although you prefer to rule out even the remotest possibility of magical beings living in these dimensions that scientists believe in, but cannot see). Or you can reject contemporary scientific theory, and flatly deny the existence of parallel dimensions/heavens/otherworldly realms/multiverses, and cling to your antiquated doctrines of materialism. The irony of the all-knowing scientifically-informed atheist putting himself or herself in check is delicious, is it not?

            Dante’s Divine Comedy outlined a journey through the 9 circles of hell, purgatory and a few levels of heaven. How many “dimensions” is that? HR Giger has been psychologically examined with the latest scientific techniques, and the conclusion was that it’s impossible for any human mind to imagine and conjure up the hellscapes and alien dimensions that he depicts. He’s merely portraying what he sees. Those are just two pithy examples, that spring to mind, of dimensional knowledge that artists had long before scientists ever started playing with their string. Science was invented originally to prove the existence of heaven, so it looks as if the goal has pretty much been achieved. Of course there’s a multitude of “unexplained phenomena”, too many to mention in this comments section, that are a nuisance to atheists who want to cudgel people’s religious belief to death. And the greatest scientist ever, Einstein’s, religious belief is also a craw that really sticks in the throat.

            When it comes to arrogance, smugness, superstition and limited breadth of mind, there’s very little difference between the devotees of Atheism and religions.

          • HeyJude

            You are quite full of yourself, and I find your attempts at intellectual superiority pathetic. You have a conversation going on in your head that has nothing to do with anything I am discussing with another. Sorry but you don’t get to define what I mean or what I think or who I am because of those voices in your head. You need to find someone else to bother, I have no interest in your nonsense.

          • chenelope

            Attributing voices in the head of another and denouncing them as a scientifically deficient, nonsensical, heathen.. it’s reassuring to see that the witch-hunting tactics of the Middle-Ages are alive and well, even though the religion du jour has changed.

            All subjective opinions aside, this was a discussion on a public forum where you expressed two irreconcilable viewpoints: 1) there are unseen dimensions, because “just trust me ok? science says so”, and 2) there are no heavens, because “pshaw, we might as well all just believe in flying spaghetti monsters in the sky as to believe those fairytales”.

            The discrepancy here is quite glaring, and at least merits some consideration. That it provoked a “you don’t even know me” response, once highlighted, suggests that it may have precipitated an admittance of the unthinkable-that they were right all along 😮

            Of course a few comments are completely inadequate for defining another’s thoughts, meanings and identity, and of course I’m not the boss of you, but you did put forward two diametrically opposing beliefs. 1) in unseen dimensions, and 2) disbelief in heavens.

            My initial post was a poorly-crafted attempt at levity, drawing attention to the similarities between contemporary science’s unproven beliefs in other dimensions, and those of antiquated religions. The 7-11 reference is based on a quasi-spiritual adventure Homer and Apu had, and is an “in joke” which unfortunately hasn’t had a good effect.

            I really regret couching my first comment in bizarre humour, and not moving to dispel the resultant acrimony it caused, instead choosing to exacerbate it. You correctly identified arrogance and smugness, and I apologise for contributing to any disconcertment or offence you might have felt. I initially joined what was a very profound discussion, wanting to add a few notes to that hymn sheet of common ground.. sorry, periodic table of elements, but in the end only managed to drop a clanger. As you’ve already admirably stated, I too have no idea what can and can’t be, and am sorry to have appeared to be trying to tell you what to think. I was merely drawing attention to a possible convergence of two theories, and a similarity in how they’re promoted.

          • rg9rts

            We have a meeting of the flat earth society on 30 Feb 14

          • HeyJude

            Also…I have really enjoyed this conversation. Glad you’ve been here to discuss it. :-)

          • konspikuous

            Glad to wax it.

          • konspikuous

            Yes, definitely something was triggered there and a lot of whatever that has nothing to do with me is being aimed my way. It’s okay.

            But wow…yes, there HAS to be parallel dimensions. Perpendicular ones too! Once one grasps that time is not linear, that all time is happening at one time, that entropy is not an ending but a beginning, that infinity has an endless amount of +1…gobs of other concepts begin to come into focus. String theory being one of them. That as big as the cosmos appears to us, it may very well be contained on but one infinitesimal intsy particle that is interacting with other equally obnoxiously tiny particles dwarfed by even quarks. That so much information is under the influence of the weak force and gravity…just, swaying to and fro on whimsical filaments of matter able to crack an entire universe into existence….

            Where’s my bottle of Advils!

          • HeyJude

            I don’t know, but when you find them, I’ll need to borrow a few! I read your link there on the Square and laughed…I think that is what you were going for. :-) I love my schadenfreude as much as the next guy, but have been loving being out here talking to you and others on this stuff. I’m a “moderate” ???? LOL
            Hope you’re weighing in on my second set of questions to you. Do you think yes or no on that train of thought?
            I wish I could go back to school and just take a class on string theory and understand just a speck of what the implications are.

          • konspikuous

            Oh sorry…I read it, a response is about to happen.

      • VincentTPackhorse

        Four huge surprises and cause for mind bending wonderment have indeed occurred in recent history:

        – the special and general theory of relativity
        – quantum mechanics
        – existence of black holes
        – the expanding (accelerating) universe originating with the bing bang (including the postulation of dark matter and dark energy)
        – [provisional accolades for string theory (which still needs further research and verification)]

        • HeyJude

          Agree Vincent! As always, it appears that the more we learn the more we realize we have yet to scratch the surface. More questions arise…now that is science! I really look forward to where that takes us. :-)

          • VincentTPackhorse

            We will boldly go where no one has gone before!

  • rg9rts

    Two words Big Little

    • HeyJude

      Are you here?

      • rg9rts


        • HeyJude

          Head over to main? Want to hear your review…

  • VincentTPackhorse

    I’m having a little trouble following the gist of this conversation. I think it must be do to sub-space interference. I’m also running low on dilthium crystals.

  • Silver Fang

    Mind boggling and humbling.

  • Julian G. Elliott

    If there are 100 billion planets in just or galaxy alone….then how can we argue intelligent life doesn’t exist beyond our galaxy?

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