Dust has never looked so beautiful! This new image from the Planck spacecraft shows giant filaments of cold dust stretching through our galaxy. The image spans about 50 degrees of the sky, showing our local neighborhood within approximately 500 light-years of the Sun. “What makes these structures have these particular shapes is not well understood,” says Jan Tauber, ESA Project Scientist for Planck. Analyzing these structures could help to determine the forces that shape our galaxy and trigger star formation.
What do these filamentary structures of dust represent? The denser parts are called molecular clouds while the more diffuse parts are ‘cirrus,’ and they do look like the wispy cirrus clouds we have on Earth. The local filaments are connected to the Milky Way, which is the pink horizontal feature near the bottom of the image. Here, the emission is coming from much further away, across the disc of our Galaxy.
The image has been color coded to discern different temperatures of dust. White-pink tones show dust of a few tens of degrees above absolute zero, whereas the deeper colors are dust at around –261°C, only about 12 degrees above absolute zero. The warmer dust is concentrated into the plane of the Galaxy whereas the dust suspended above and below is cooler.
Planck will help us study the biggest mysteries of cosmology, such as how the Universe and galaxies formed. This new image extends the range of its investigations into the cold dust structures of our own Galaxy.