This week’s image from the Hubble Space Telescope reveals a striking display of galaxies overlapping in a mesmerizing swirl. What seems to be four galaxies are showcased in this image, but appearances can be deceiving.
The dominant presence on the right side of the image is NGC 1356, an exquisite barred spiral galaxy reminiscent of our Milky Way. Also known as the Great Barred Spiral Galaxy, it boasts a prominent bar rich in stars at its center. Situated near NGC 1356 are two smaller spiral galaxies, LEDA 467699 and LEDA 95415, while IC 1947 can be spotted on the left side of the image.
This image from the NASA/ESA Hubble Space Telescope features a richness of spiral galaxies: the large, prominent spiral galaxy on the right side of the image is NGC 1356; the two apparently smaller spiral galaxies flanking it are LEDA 467699 (above it) and LEDA 95415 (very close at its left) respectively; and finally, IC 1947 sits along the left side of the image. ESA/Hubble & NASA, J. Dalcanton, Dark Energy Survey/DOE/FNAL/NOIRLab/NSF/AURA; Acknowledgment: L. Shatz
The interesting twist in this image is that, despite the impression that the three galaxies on the right are clustered together, and the one on the left is further away, the reality is quite different. The two LEDA galaxies appear to be on top of NGC 1356, but they are actually millions of light-years apart. The visual proximity is purely due to our observation angle, giving the illusion that they occupy the same patch of the sky when viewed from Earth.
Conversely, the apparently solitary IC 1947 is in fact much closer to the large galaxy NGC 1356 on the right. They are separated by less than 400,000 light-years, making them relatively close neighbors in this cosmic neighborhood.
Similar images have been captured by Hubble in the past, showcasing galaxies that seem to overlap but are actually positioned at different distances from Earth. It’s a challenge to discern between these images and those where galaxies are genuinely interacting with each other. One telling sign of interacting galaxies is the gravitational forces distorting one or both galaxies as they come into close proximity.