(Phys.org)—The brilliant cascade of stars through the middle of this image is the galaxy ESO 318-13 as seen by the NASA/ESA Hubble Space Telescope.
Despite being millions of light-years from Earth, the stars captured in this image are so bright and clear you could almost attempt to count them.
Although ESO 318-13 is the main event in this image, it is sandwiched between a vast collection of bright celestial objects. Several stars near and far dazzle in comparison to the neat dusting contained within the galaxy.
One that particularly stands out is near the centre of the image, and looks like an extremely bright star located within the galaxy. This is, however, a trick of perspective. The star is actually in the Milky Way, our own Galaxy, and it shines so brightly because it is so much closer to us than ESO 318-13.
There are also a number of tiny glowing discs scattered throughout the frame that are more distant galaxies. In the top right corner, an elliptical galaxy can be clearly seen, a galaxy which is much larger but more distant than ESO 318-13.
More interestingly, peeking through ESO 318-13, near the right-hand edge of the image, is a distant spiral galaxy.
Galaxies are largely empty space – the stars within them only take up a small volume. Providing a galaxy is not too dusty, it can be largely transparent to light coming from the background. This makes overlapping galaxies like these quite common.
Explore further: WISE survey finds thousands of new stars, but no 'Planet X'