Why are we to believe there are billions of stars and galaxies?

Question

I am a "doubting Thomas" on this. I just sounds hard to comprehend.

Answer 1

Try looking up at the stars at night and you will see them. OR buy yourself a telescope and look up at the stars, you'll be sure to see them.

Answer 2

First, you should realize that the universe is very homogenous, meaning that regardless of which direction you look into it the distribution of galaxies is pretty much the same. Based on this fact, astronomers can survey several regions of the universe, count the number of galaxies, then from that extrapolate the approximate total of galaxies in the entire universe. For example, if you count the number of galaxies in 10 different regions of space that are each 5 degrees wide and come up with an average of 564 galaxies per region, then it's a simple step to project that average across the entire universe.

As for the total number of stars in the universe, the same technique is used, only now it's the brightness of representative galaxies that reveal the number of stars contained within them--the brighter the galaxy the more stars. Using this system, one research group recently came up with a figure of 70-TRILLION stars in the entire universe.

Answer 3

The USNO A2.0 star catalog lists about one billion stars in our galaxy. And we know that there are many more either too faint and distant to be seen or hidden by stars, gas, or dust in the foreground, so the total (for the Milky Way Galaxy) is probably around 100 billion.

As for the number of galaxies, the Hubble Ultra Deep Field showed about 10,000 galaxies in a tiny patch of sky 3 arcminutes square (the Moon appears about 30 arcminutes across). There was nothing special about the area photographed, other than that it was devoid of foreground objects that might block the view. If we assume that the galaxy density seen in the UDF is typical, we come up with over 150 billion galaxies. It's a big universe; get used to it.

Answer 4

I think I understand at least part of your question. Of course, when you look up at the night sky, you can see stars. If you're in a city you might only see five or ten on any night. Suburbs: a few dozen, but it's still too bright. If you're in the country, maybe a couple of thousand, tops. So why BILLIONS?

The answer is that the evidence is extremely strong for there being billions of stars. First let's just take our own galaxy. If you're able to see the Milky Way with the naked eye, it usually just looks sort of cloudy. Telescopes with better resolution show these "clouds" to be masses of countless stars. From telescopic observation we can know two things: (1) our own galaxy contains about 100 billion stars (by averaging for known points of light over areas) and (2) our galaxy has a spiral shape.

Now we can move to other galaxies. When some nearby galaxies, like Andromeda and even the Magellanic Clouds (sattelite galaxies of our own) were first discovered, some scientists thought they were just gas clouds, nebulae of some sort. But over time the evidence came in: spiral shape (for some at least), huge distance from us (as determined by red shift), and the kinds of electromagnetic emissions all pointed to one and only one conclusion: these were galaxies like our own, filled with hundreds of billions of stars.

As telescopic observation improved, and other ways of observing distant space became available (radio, microwave, gamma ray, x-ray), we learned that there are countless clusters of galaxies distributed througout the universe. Most estimates put them on the order of 100 billion.

So the best evidence right now (and our belief should track the evidence) is that there are about 10,000 billion stars in our universe. That's a lot!

Answer 5

Well quite frankly, we can see them!

It's much like looking down on the Earth. Maybe you see a city and if you look closer, you can see people in that city...lots of people. You can estimate the general population of the city from your observations...but wait, you see another city, and another. Maybe some cities you can't see directly because they're fogged in a lot but you can see roads going to them and maybe lights from them at night so you know they're there and likewise you can estimate the population of that city. From all of this you conclude that Earth has thousands of cities and towns and billions of people, even though you can't count every single one individually.

Going back to stars and galaxies, the dark sky is filled with thousands of stars that are visible to the naked human eye. Unfortunetly most people don't realize this because they live in cities with heavy amounts of light pollution and are lucky if they can see five bright stars and Venus or Jupiter.

You may be interested in this photograph.

http://imgsrc.hubblesite.org/hu/db/1996/01/images/a/formats/full_jpg.jpg

This is the hubble deep field photograph. Basically they took the Hubble telescope (which is in orbit, away from light pollution and out of the atmosphere) and pointed it at the emptiest part of the sky they could find, and took a really long exposure picture. Hundreds of galaxies showed up. This image spans 1/30th the area of a full moon. The only star in it is the bright guide star in the middle. The rest are galaxies.

They get this when they point it at any "empty" point of sky.

Answer 6

Hi Tom,
Look on a clear night some night, and the best in a boat, on a lake, no wind very calm. You'll see more stars and other constillations in the sky above than you can count. We have 4 seasons every season it changes. Find the big dipper the little dipper the north star and gets more exciting.

Answer 7

the version is technological expertise. technological expertise calls for repeatable experiments that yield effects (info) that help a theory and no experiments that coach the perception pretend. faith is in accordance with faith - hence there are not any experiments that could want to coach it or disprove it. all of us comprehend billions of stars exists because you are able to open your eyes (outside of a city) and observe more desirable than 10,000 stars which include your eyes. you are able to then get a huge telescope and observe thousands and thousands extra. i think you'll run out of time formerly you would possibly want to count number all that you will be able to work out. As for approaches to inform the astounding dots contained in the sky are stars, properly, you would possibly want to study an astronomy e book to comprehend how scientists make repeatable measurements that coach previous sensible doubt that they are in reality stars. Atoms exist because thousands and thousands of experiments were executed that each and each one ensure their existence and not in any respect one attempt has ever disproved their existence. they're even growing to be considered with more suitable electron microscopes. imagine about technological expertise next time you position a burrito in a microwave oven to warmth up. it isn't magic, inspite of the actual undeniable reality that it type of sounds like it. finally, please observe that the bible you study isn't an unique - it is been translated and edited. The "King James Bible" is one among the most worry-loose and is wisely time-honored to have had complete books bumped off that were in Bibles formerly King James.

Answer 8

Order cable t.v. and watch the Discovery Channel. Oh yea...don't forget to open your closed mind. Just because it's hard for you to comprehend does not mean it's not real. In fact it's hard for me to comprenhend that you can even use a computer.....but surprise....here you are!!!

Answer 9

A few million have been counted and cataloged. The rest are estimated in various ways.

Answer 10

study astronomy and the basis for modern cosmological models ... that is, if you would prefer to put effort forth to address this doubting-point.

read, read ,read ... use your mind to learn about the world in whic hyou live

you will enjoy the path

peace