It would be great to take a trip outside our Milky Way Galaxy, far enough to get a nice image of the galaxy with all its stars, nebulae and spiral arms. We would be able to spot our sun among all the stars, in the bigger galactic context. Unfortunately we’d need to go a good distance, say out as far as Andromeda, to capture that image. Andromeda is 2.5 million light years away, so if we could travel as fast as light it would take 5 million years to make that round trip.
The image at top is a graphic illustration of the Milky Way, as we understand it in 2021, from Wikipedia. The original image was published in 2008 by NASA/JPL-Caltech (author R. Hurt). I believe that the first rough map of the galaxy was produced by William Herschel, who assumed our sun was in roughly the middle of the galaxy.
The image below is of a similar barred spiral galaxy, known as Messier 109. This image has been stretched on one axis to simulate the appearance if it were face-on to us. It has also been rotated and cropped.
M109 is remarkably similar to the artist’s conception of the Milky Way. It is estimated to have roughly the same number of stars as the Milky Way, and to have roughly the same diameter.
So if anyone asks you for a picture of the Milky Way galaxy, I suggest you substitute this image of M109 and add NASA’s graphic as proof. It’ll be a lot easier than that 5-million-year road trip.
Here's that comparison again, side by side:
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