These sinister eyes gazing out from the depths of space star in a new Halloween-themed image, using data from both the Hubble Space Telescope and the James Webb Space Telescope. It shows a pair of galaxies, IC 2163 on the left and NGC 2207 on the right, which are creeping closer together and interacting to form a creepy-looking face.
The two galaxies aren’t colliding directly into one another, as one is passing in front of the other, but they have passed close enough to light scrape by each other and leave indications. If you look closely at the galaxy on the left, you can see how its spiral arms have been pulled out into an elongated shape, likely because of its close pass to the gravity of the other nearby galaxy. The lines of bright red around the “eyes” are created by shock fronts, with material from each galaxy slamming together.
As destructive as all of this sounds, however, it also helps to drive star formation. That’s because the power of the gravitational forces pulling at the dust and gas in each galaxy can create compressed regions, where the higher density makes it more likely for clumps to form, which can eventually turn into stars. This creates bright, young stars that shine brightly throughout both galaxies.
“Both galaxies have high star formation rates, like innumerable individual hearts fluttering all across their arms,” Webb scientists explain. “Each year, the galaxies produce the equivalent of two dozen new stars that are the size of the Sun. Our Milky Way galaxy only forms the equivalent of two or three new Sun-like stars per year. Both galaxies have also hosted seven known supernovae in recent decades, a high number compared to an average of one every 50 years in the Milky Way. Each supernova may have cleared space in the galaxies’ arms, rearranging gas and dust that later cooled, and allowed many new stars to form.”
You can see the areas of star formation by looking for regions glowing blue (from Hubble data) and pink and white (from Webb data). The two telescopes generate different-looking images that you can see side by side here, because they operate in different wavelengths. Hubble looks in the visible light spectrum, similar to what is seen by the human eye, while Webb looks in the infrared region, seeing things that would be invisible to us and highlighting busy “starburst” areas where many new stars are being formed.