Rex Trulove
There are many people who are totally uninterested in science of any sort. However, I find it hard to understand why anyone wouldn’t think that our Milky Way galaxy isn’t an astounding and amazing place.
Many of the facts we know about the Milky Way are mind-boggling and hard to grasp. For example, it has the shape of a flattened disk with a central bulge that is about 100,000 light-years from edge to edge and 1,000 light-years thick in the central bulge. This sounds simple enough, except that it is really hard to imagine that size and distance.
Light travels at about 186,000 miles every second. A light-year is the distance light travels in a year, roughly 5.88 trillion miles. A trillion is a number so large that it is impossible to fully grasp. Consider that a person who is 30-years-old has been alive for 946,708,560 seconds. That is less than 1 billion seconds. A trillion is 1,000 billion. Light travels about 5,880 billion miles in a year. The Milky Way is about this distance, 100,000 times. In fact, this is the reason we measure such distances in light-years; to allow us to somewhat grasp the distance that is involved, though we still don’t actually grasp the number because it is so large.
Our solar system is located about 30,000 light-years from the center of the milky way and there is so much dust and so many stars that we can’t even see the center of the galaxy with an optical telescope. We can see it, though, using radio telescopes since radio waves cut through the dust.
The Milky Way spins around the center, rather like the earth revolves around the sun. Our solar system is moving around the center of the galaxy, along with the other stars, at around 515,000 mph. Yet it takes about 230 million years for the solar system to revolve once around the center of the Milky Way.
In the Milky Way, there are over 200 billion stars. While there are relatively few other stars near the solar system, stars are densely packed near the center of the galaxy. If our solar system was near the center of the galaxy, nighttime would be nearly as bright as daytime.
There are also two black holes at the center of the galaxy, each with a mass that is several billion times that of our solar system.
Even with all of that; dust, gas, stars, planets, black holes, and so forth, the milky way is mostly empty space. Yet, for all that we can see and measure; the gas, dust, planets, and stars we can see, nine-tenths of the matter in the galaxy is undetectable and unseeable. We know this because at the speed the milky way is rotating, if it didn’t have the extra mass that we can’t see, the galaxy would fly apart.
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Wouldn’t you say that this makes the Milky Way a truly amazing place?
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Yes
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No
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A little bit
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I’d be interested in knowing more
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In the time of Galileo, this article would have gotten you excommunicated from the church! Interesting how we have come to move towards the reality of the universe.
That is quite true. For 1,500 years, the accepted thought was that the earth was the center of the universe and that everything we see in the night sky revolved around the earth. A big problem that the church had, at the time of Gallileo, was that nowhere in the Bible does it say or even hint that the earth was the center of the universe. The church could find no justification for believing that it was. Yet, it is fairly recent that the church reinstated Galileo’s standing in the church.
a sad reality all the way around.
Still when we gaze upon the milky way, there is much to be seen.
What we can see is mind-boggling, too. Yet, what we can’t see is even more so.
Carl Sagin famously said, there are billions of stars in our galaxy. but trillions in the universe.
(he never said billions and billions.)
One of the biggest difficulties is in actually grasping the numbers. “Trillion” is a word that is sometimes tossed around, but few people understand just how large that number is. Even a billion is a large number to grasp.
ah but both of us come from the computer world where trillions has a meaning!
I have always heard that the way a person made it into this world through the galaxy is the way he or she will also leave it. What I found amazing and truthful about this is that all my life on my left arm I have beauty marks all lined up perfectly just like the Milky Way and so I know I came from there and through there I shall return to wherever my loved ones wait for me.
What many people don’t realize is that in no way does any of it mean that there isn’t a God, either. If anything, it is a strong indication that there is a God because it is all so complex that it literally couldn’t have happened by chance.
Since I was in grade school I am already fascinated with astronomy.
I think that I started becoming interested in astronomy at about the same age.
Yws I agree and we have so much left to learn.
That is certain. We’ve barely begun to learn about our galaxy and the universe.
Nice story. Yeah agree with you – our galaxy is a truly amazing place! Thanks.
The more we learn about it, the more amazing it is, too.
Yeah agree with you , truly amazing place
Every time I start thinking about it, I’m astounded.