The European Space Agency released an image of the Orion Molecular Cloud and it is beautiful — filled with blue hues and textures evoking sea waves. But in addition to resembling a scene from an exotic holiday, it is also highly reminiscent of The Starry Night, Vincent van Gogh's best-known work.
A quick search through Google for similar images yields van Gogh's painting as one of the results. Quite apt, considering that the image does capture a portion of the sky, right? The image released by the ESA is based off data from the Planck satellite, which scanned the sky from 2009 to 2013 in an effort to observe the cosmic microwave background, the universe's most ancient light. While doing so, the satellite picked up foreground emission coming from the Milky Way and other galaxies.
Earth's galaxy is filled with diffused dust and gas — a mix that grows denser and creates giant clouds of gas from which stars form. While only present in trace amounts, dust is a critical ingredient in the formation of interstellar clouds – shining brightly at certain wavelengths probed by the Planck satellite – relaying information that can be used to better study how clouds form.
Additionally, dust grains feature elongated shapes and have the tendency to orient their longest axis at right angles toward the Milky Way's magnetic field. This makes the dust emissions partly polarized, vibrating in a certain direction. But since the Planck satellite was fitted with detectors sensitive to polarization, its scans also hold data about the magnetic field's direction as it threads the galaxy.
The image released by the ESA provides a visualization of the total intensity of the emitted dust, shown in a color scale with the magnetic field's direction indicated as texture. The areas with blue hues represent regions containing small amounts of dust, while red and yellow portions deflect hotter and denser clouds filled with more gas and dust.
The Orion Molecular Cloud Complex is shown as red clumps at the image's center. Just around 1,300 light-years away from the sun, it is considered to be one of the closest of large star formations. The Orion Nebula, also called M42, is shown as the most prominent of the red clumps. In the Orion constellation, the nebula can be seen by the naked eye just under the three stars forming Orion's belt.
Astronomers believe that the magnetic field's turbulent structure and the presence of star-forming clouds in the image have connections to the powerful forces that influence the birth of stars.