Compass and Scale Image for SN Refsdal and MACS J1149.6+2223
The powerful gravity of a massive cluster of galaxies in this Hubble Space Telescope image is producing multiple images of a single distant supernova behind it.
The foreground cluster is acting like a giant cosmic lens, bending and magnifying light from the exploding star in an effect called gravitational lensing.
The enlarged inset view reveals four images of the supernova, spotted on Nov. 11, 2014, arranged around a giant elliptical galaxy within the cluster. The light from the supernova passes so closely to the galaxy's dense core that several light paths are redirected and focused toward Earth. The result is that astronomers see four images that form a cross-shaped pattern called an Einstein Cross. The blue streaks wrapping around the galaxy are the stretched images of the supernova's host spiral galaxy, which has been distorted by the warping of space.
Computer models of the cluster predict that another image of the stellar blast will appear within five years. The red circle marks the possible location of the next supernova image. Astronomers may have missed an earlier appearance of the supernova in 1995, as marked by the blue circle. These multiple appearances of the exploding star are due to the various paths its light is taking through the maze of clumpy dark matter in the galactic grouping. Each image takes a different route through the cluster and arrives at a different time, due, in part, to differences in the length of the pathways the light follows to reach Earth.
The elliptical galaxy and its galaxy cluster, MACS J1149.6+2223, are 5 billion light-years away from Earth. The supernova, dubbed Supernova Refsdal, is 9.3 billion light-years away.
This image combines data from three months' worth of observations, taken in visible light by the Advanced Camera for Surveys and in near-infrared light by the Wide Field Camera 3.
NASA, ESA, and S. Rodney (JHU) and the FrontierSN team; T. Treu (UCLA), P. Kelly (UC Berkeley), and the GLASS team; J. Lotz (STScI) and the Frontier Fields team; M. Postman (STScI) and the CLASH team; and Z. Levay (STScI)