The Scale of Our Universe
To give an idea of the scale of things in space, I have provided this series of images and captions.
These are real photographs of the Sun, the eight canonical planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune going from left to right), and an illustration of dwarf planet Pluto. Although their distances are not accurately represented here, their sizes are.
Now let us move farther out. This is what we think our galaxy looks like when standing outside looking toward it. Of course cannot actually ''see'' our galaxy in this way; however, astronomers have based this model upon very careful and well-informed measurements of the galactic structure as seen from the ground. Our sun is just one of over 150 billion stars in our galaxy, its position being shown by the arrow in this diagram. At this scale, the Sun is indistinguishable; it blends into the great mass of other stars and galactic gas and dust.
This image of the Hubble Ultra Deep Field puts all of this into even further perspective. Our galaxy is just one of many hundreds of billions of galaxies in our universe, a few of which are visible in this breathtaking image.
The bottom line: space is REALLY, REALLY BIG!!!
Image Credits: NASA