This release features two composite images of the Cas A supernova remnant, a structure resulting from the explosion of a star in the Cassiopeia constellation. The primary image depicts Cas A as a spherical blue and turquoise cloud streaked with gold. In the supplementary image, below, Cas A is blanketed by short, straight, white and green lines that illustrate the magnetic field across large regions of the remnant.

In the primary image, the spherical cloud resembles a hazy ball of turquoise and neon blue lightning, marbled with veins of gold. The blues represent data from the Chandra Observatory, the turquoise is from NASA's Imaging X-ray Polarimetry Explorer (called IXPE), and the gold is courtesy of the Hubble Telescope.

In the supplementary image, short digital lines cover Cas A like highly organized grains of rice. Most of the lines are white, though patches of green lines are present around the outer edges of the overlay. The orientation of the lines indicates the direction of the magnetic field across the supernova remnant. The resulting arrangement is quite complex, but patterns within the blanket of orderly lines are evident.

At the center of the image, straight white lines are diagonally oriented, pointing to the upper left and lower right. Moving from the center to the outer edges, the lines begin to turn. Some turn toward our lower left, others toward our upper right. This gives the impression of a magnetic field with two primary streams directed outward in opposite directions. The green lines show regions where the magnetic field is most easily detected.

This graphic combines data from NASA's Imaging X-ray Polarimetry Explorer (IXPE) with an X-ray image from Chandra (blue) and a view in optical light from Hubble (gold) of the Cassiopeia A (Cas A) supernova remnant. The lines in this graphic come from IXPE measurements that show the direction of the magnetic field across regions of the remnant. Green lines indicate regions where the measurements are most highly significant. These results indicate that the magnetic field lines near the outskirts of Cas A are largely oriented radially, i.e., in a direction from the center of the remnant outwards. The IXPE observations also reveal that the magnetic field over small regions is highly tangled, without a dominant preferred direction