Picture of the Milky Way?

Question

http://kartha-pes.sulekha.com/mstore/kartha-pes/albums/Ramblings%20of%20a%2060%20year%20old/Milky_Way_schematic.jpg

Here is the picture. HOW THE h**l can people get this sort of image and circle a tiny *** part and say "where here" "the sun is here" its dumb.

Its just ridiculous.

Answer 1

No it isn't! We can map ourselves pretty accurately, as a matter of fact, working out our distance from galactic central point was a project I was set as part of my Astronomy degree (Year one at that!) There are many techniques, I used globular clusters!

Globular star clusters are gravitationally bound groups of 100,000 to 1 million stars. They are compact, spherical “balls” of stars with very high stellar densities in their centres . They contain a high proportion of 'Cepheid variable' stars. These stars can be used as 'standard candles' - we can work out their true magnitude (Luminosity) and therefore by contrasting that with their apparent magnitude, their distance from us. Combining this with measurements of their tangential motion, and the fact that globular clusters tend to be found in the galactic halo, it is possible to work out our position relative to the rest of the galaxy.

The relationship between magnitude and distance can be expressed;

m-M = 5 log d – 5

where m is apparent magnitude, M is absolute magnitude, and d is the distance in parsecs

I calculated GCP to be 27710.11 light years away, in the constellation of Sagatarius!

Answer 2

You will find that as you get older and having left school and broadened your horizons, you will find that a representation, such as the picture you short cut to, will become far more understandable.

Answer 3

This is not a photograph or real "picture" it is a conceptualized image, a scientific rendering if you will.  It is intended to show the large-scale structure of our Milky Way galaxy, and the relative location of our solar system within it.  Think of it as a map, long before there were artificial satellites or aircraft, people were able to make maps of the continents of the earth, this would show the shapes of islands, continents etc, without directly imaging them from overhead.  This map is created in a similar way, with "mapped" coordinates of objects, mostly utilizing infra-red imaging techniques, because infra-red detectors can "see through" the dust in the galaxy which normal light can not penetrate.

Answer 4

Wait a minute. You don't understand this picture, so therefore it's bogus? Is it possible that you just don't understand it? Why do you assume that anything you don't understand is dumb?

The picture is not a photograph - obviously. It's an artist's concept based on similar galaxies that we see all around us - combined with the clear observation that we can see the next outer arm, the next inner arm, or the bright central bulge of our own Milky Way galaxy on any clear night - depending on the season and the direction in which we look. It is intended to provide an idea of where we are within our galaxy and the relative size of our solar system compared to it. It was created by a person with a paint brush and an intelligence - not a computer and a mouse clicking finger.

This knowledge and the reasonably accurate pictures that go along with it are about a century old. Your question is a little late and a bit arrogant. Perhaps you should spend a few evenings with a telescope and a knowledgeable friend - it would be enlightening.

Answer 5

We can measure distances to stars and nebulas pretty accurately, and we also know what typical spiral galaxies look like. It's no big miracle that we can plot stars in the 3D space around us, and figure out what it looks like from the outside. I think you underestimate the scientists and the hundreds of years of research.

Answer 6

Smarter people than you and i.

Answer 7

through basic plotting techniques, same way boats on the olden days knew where they were

Answer 8

The pictures you're talking about are not of the Milky Way, they're of other similar galaxies, used as an example - a good book would point that out clearly to avoid exactly this kind of confusion.

From what astronomers can tell, our galaxy is a classic spiral, and so they use images of other spiral galaxies to show people what our own looks like. Simple as that.

Or maybe there was an astronomer with a camera on the end of a really long stick...

Answer 9

Great Pic.

Answer 10

People so smart that they know the difference between "we're" and "where" did it.

Answer 11

No, it is just not easy to understand for you, how such a map of our own galaxy can be made.

Let's start at the simplest beginning: We do know how other galaxies look like. For a long time, our view of our own galaxy was actually the Andromeda galaxy.

We did know very quickly how far away from the core of the galaxy we must be, by measuring the relative velocities of stars. With such observations we also already had a good view of the first 10000 LY around us. This told us, the galaxy had 5 arms. Later, we found out that the galaxy had only 4 arms and two small spurs, with one of these being the home of our sun.

The next major problem was the hub of the galaxy - it is full of dust and bright and most technology was not able to view it. But modern IR-, X-Ray-, Gamma- and radiotelescopy  allowed us to look through the dust and see, that we actually have no true spiral galaxy, but in reality, a bar galaxy.

We still have a large region opposite of us, which we can't see. We will very likely not see it soon. But we now have a very good map of the part we can see.

Answer 12

We cannot photograph the Milky Way galaxy from outside it, at least not yet.  What we can do, and what I do frequently in my daily work, is photograph THROUGH the Milky Way at many different frequencies, which enables us to gradually build a pretty accurate picture of what it looks like from outside.  We know it is a barred spiral, similar to many galaxies we can see from above their galactic planes, and we know roughly where we are in our Galaxy.

Answer 13

It is neither dumb nor ridiculous. It is the result of hundreds of years of study of our region of space. We can SEE the galaxy from within, and our view makes it pretty clear we are a long way off from the centre but not right on the edge. We can work out distances using various methods which have been demonstrated to be effective. We can use other galaxies as guides for what our own might look like. The result is a representation of our galaxy and our own position in it that best fits all the observations that have been made. It may not be 100% right, and we'll never really know, but unless you can come up with a better answer for what is observed then what makes you think you are justified in writing off decades or even centuries of research as 'dumb'?