Posted on 07/25/2018 11:18:26 PM PDT by Simon Green
The sun may appear to be the largest star in the sky but that's just because it's the closest. On a stellar scale, it's really quite average — about half of the known stars are larger; half are smaller. The largest known star in the universe is UY Scuti, a hypergiant with a radius around 1,700 times larger than the sun. And it's not alone in dwarfing Earth's dominant star. The largest of all
In 1860, German astronomers at the Bonn Observatory first cataloged UY Scuti, naming it BD -12 5055. During a second detection, the astronomers realized it grows brighter and dimmer over a 740-day period, leading astronomers to classify it as a variable star. The star lies near the center of the Milky Way, roughly 9,500 light-years away.
Located in the constellation Scutum, UY Scuti is a hypergiant, the classification that comes after supergiant, which itself comes after giant. Hypergiants are rare stars that shine very brightly. They lose much of their mass through fast-moving stellar winds.
Of course, all stellar sizes are estimates, based on measurements taken from far away.
"The complication with stars is that they have diffuse edges," wrote astronomer Jillian Scudder of the University of Sussex. "Most stars don't have a rigid surface where the gas ends and vacuum begins, which would have served as a harsh dividing line and easy marker of the end of the star."
Instead, astronomers rely on a star's photosphere, where the star becomes transparent to light and the particles of light, or photons, can escape the star.
"As far as an astrophysicist is concerned, this is the surface of the star, as this is the point at which photons can leave the star," Scudder said.
(Excerpt) Read more at space.com ...
“On a stellar scale, it’s really quite average — about half of the known stars are larger; half are smaller.”
Misleading statement.
If you take, for example the weight of all adult humans from the very small to the hugely fat the range is about 65 pounds (Very tiny women, pigmies) to 850 pounds for the fattest guy alive. Half of that, (which is how they get this stat) is is just over 400 pounds. There are not many 400+ pound people walking around.
Our star is actually in like the 75th percentile of star size. Or that is what the astronomy professor in that class I took in university all those years ago said.
Interesting post. Thanks.
There used to be a lot of people at Free Republic who avidly read all the science and technology posts.
That number has conspicuously declined in recent years.
Try not to get discouraged with the limited viewership, and thanks again.
Seems like maybe the guy who categorized the first giant star was a bit too optimistic about what else was to come?
It reminds me of the days when movie theaters sold popcorn in large, extra-large, and jumbo sizes, instead of small, medium, and large.
-PJ
My question is, what the heck is this thing?
Maybe I've seen too much sci-fi, but it looks like some kind of force field creating a void in the corona, while plasma (or something) is transferred from the surface of the sun in three vortexes which combine into one. It's really nuts to look at, especially the way it jets away.
“Our star is actually in like the 75th percentile of star size. Or that is what the astronomy professor in that class I took in university all those years ago said.”
You just don’t know how much has changed since then...
Elvis Presley. He’s bigger than the universe!
Arcturus is pretty big too. As I recall, would fill the 360 degree space created by Mars orbit around the sun. And it is a Red Star too.
There used to be a lot of people at Free Republic who avidly read all the science and technology posts.
—
Many were kicked during one or more purges, others passed away.
My question is, what the heck is this thing
Just a ship refueling, or perhaps a refueling station refilling. There are others on the video which are clearer and not round. nothing to worry about, just normal operations. Go back to sleep.
since the proliferation of junk science and bubblegum science there’s a lot of noise and not much signal
See the different sizes of planets and stars.
https://upload.wikimedia.org/wikipedia/commons/thumb/c/cc/Star-sizes.jpg/1280px-Star-sizes.jpg
We are just a bunch of marbles that alien kids play with.
Our star is rather a common, garden variety sized star. Nothing too big, not to small. I was under impression Betelgeuse was the biggest star.
Hale-Bopp.
There’s an outside chance it’s some kind of natural phenomenon, isn’t there? Some kind of tightly wound magnetic bubble which pinched off from the sun? But why would it hover so close to the sun with vortexes forming between it and the photosphere, and then scoot away suddenly?
If that enormity (much bigger than Earth) is something artificial, whoever made it probably regards us in the same way we regard bacteria.
I believe that astronomers have since concluded that most stars are probably dim red dwarfs, whose detectability falls off sharply with distance. So star demographics have shifted.
The Sun is tired of being in the shadow of Canis Majoris.
I've thought that, too. One day the alien ship will visit and the kid will say, "Daddy, I want that little one with all the water. Can I take it home?"
Lights out.
What you described is not how a statistical average is calculated. True average is calculated by adding the values for EVERY item in the group, and then dividing by the number of items in the group. This gives a much different result, and makes the statement accurate.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.
