The latest breathtaking photograph captured by the Hubble Space Telescope might remind you of cotton candy, but it’s actually a glimpse into a nebula found in the neighboring Large Magellanic Cloud. This satellite galaxy of the Milky Way lies approximately 160,000 light-years away. The nebula features a vibrant array of dust and gas that emits various colors, reflecting the different physical processes occurring within it.
To understand how Hubble achieves its striking and colorful imagery, it’s important to know how its cameras operate. Unlike your smartphone camera, which takes a quick snapshot, Hubble’s instruments, like the Wide Field Camera 3, perform multiple observations of the same object while utilizing different filters.
Each of these filters allows the camera to isolate specific wavelengths of light. In this instance, five distinct filters were employed, targeting not only visible light but also portions of the ultraviolet and infrared spectrum.
This technique enables Hubble to collect multiple black-and-white images of the same celestial object at different wavelengths. When these images are combined, they form a single, vibrant colored photograph, which you can admire in detail below.
ESA/Hubble & NASA, C. Murray
“When image-processing experts combine raw data from these filters into a colorful composite, they assign colors to each filter,” Hubble scientists state. “Visible-light data corresponds to the color that the filter permits, while shorter wavelengths, like ultraviolet, are usually represented as blue or purple. In contrast, longer wavelengths like infrared tend to be shown in red.” This coloring method provides a clearer understanding of phenomena happening in wavelengths outside of human visibility.
The process of creating these images is akin to the techniques used by the James Webb Space Telescope, utilizing filters and composite methods to produce incredible representations of hidden cosmic entities. This work demands a blend of scientific acumen and a touch of artistic sensibility from the image processors.
