NASA Webb ‘Pierces’ Bullet Cluster, Refines Its Mass
Hello darkness my old friend…
What you are (not) seeing, highlighted in blue, is dark matter. Webb was used to precisely map out the dark matter that is part of the makeup of two colliding galaxy clusters, with help from NASA's Chandra X-ray Observatory. Webb captured more extremely faint galaxies in the Bullet Cluster than ever seen before (as well as foreground stars), allowing scientists to accurately determine the mass of the cluster.
Chandra data shows the hot, X-ray-emitting gas present between the two galaxy clusters (highlighted in pink). As these two galaxy clusters collided, this gas was dragged out and left behind. Webb observations show that the dark matter (in blue) still lines up with the galaxies and was not dragged away.
Normally galaxies consist of gas, dust, stars, and dark matter, all combined, even when the galaxies are part of a cluster. Observing this separation between the gas and dark matter is unusual.
While we cannot see dark matter because it does not emit light, it has mass and gravitational influence on light we can see. It can act like a lens, magnifying and warping objects behind it. Imagine dark matter as water so clear you can’t see it unless the wind ripples it. The ripples will distort the shapes of any pebbles below its surface. Likewise, dark matter distorts the shapes of distant background galaxies. We can’t see it, but we see its effects.
Read more at the link in our bio.
Image credit: NASA, ESA, CSA, STScI, CXC
Science credit: James Jee (Yonsei University, UC Davis), Sangjun Cha (Yonsei University), Kyle Finner (Caltech/IPAC)
Image description: Webb near-infrared data combined with Chandra X-ray data of the Bullet Cluster show many overlapping objects, including foreground stars, galaxies in galaxy clusters, and distorted background galaxies behind the galaxy clusters. The objects are all at various distances set against the black background of space. Most galaxies appear as tiny fuzzy ovals in white, orange, or red. A slightly larger, very bright, light blue spiral galaxy is at center. To its immediate left and right are two large bright pink splotches representing X-rays. The right pink area has a rounded nose facing right, where it is darker pink, and fades to the left as a triangular shape. This is referred to as the Bullet. To the far left and far right, next to the pink regions, are two blue regions representing dark matter mass. The left blue region is a large, long oval at an angle. The blue region at right is a far smaller oval.
NASA Webb ‘Pierces’ Bullet Cluster, Refines Its Mass
Hello darkness my old friend…
What you are (not) seeing, highlighted in blue, is dark matter. Webb was used to precisely map out the dark matter that is part of the makeup of two colliding galaxy clusters, with help from NASA's Chandra X-ray Observatory. Webb captured more extremely faint galaxies in the Bullet Cluster than ever seen before (as well as foreground stars), allowing scientists to accurately determine the mass of the cluster.
Chandra data shows the hot, X-ray-emitting gas present between the two galaxy clusters (highlighted in pink). As these two galaxy clusters collided, this gas was dragged out and left behind. Webb observations show that the dark matter (in blue) still lines up with the galaxies and was not dragged away.
Normally galaxies consist of gas, dust, stars, and dark matter, all combined, even when the galaxies are part of a cluster. Observing this separation between the gas and dark matter is unusual.
While we cannot see dark matter because it does not emit light, it has mass and gravitational influence on light we can see. It can act like a lens, magnifying and warping objects behind it. Imagine dark matter as water so clear you can’t see it unless the wind ripples it. The ripples will distort the shapes of any pebbles below its surface. Likewise, dark matter distorts the shapes of distant background galaxies. We can’t see it, but we see its effects.
Read more at the link in our bio.
Image credit: NASA, ESA, CSA, STScI, CXC
Science credit: James Jee (Yonsei University, UC Davis), Sangjun Cha (Yonsei University), Kyle Finner (Caltech/IPAC)
Image description: Webb near-infrared data combined with Chandra X-ray data of the Bullet Cluster show many overlapping objects, including foreground stars, galaxies in galaxy clusters, and distorted background galaxies behind the galaxy clusters. The objects are all at various distances set against the black background of space. Most galaxies appear as tiny fuzzy ovals in white, orange, or red. A slightly larger, very bright, light blue spiral galaxy is at center. To its immediate left and right are two large bright pink splotches representing X-rays. The right pink area has a rounded nose facing right, where it is darker pink, and fades to the left as a triangular shape. This is referred to as the Bullet. To the far left and far right, next to the pink regions, are two blue regions representing dark matter mass. The left blue region is a large, long oval at an angle. The blue region at right is a far smaller oval.