James Webb Space Telescope finds supernova 'Hope' that could finally resolve major astronomy debate
"The supernova was named 'supernova Hope' since it gives astronomers hope to better understand the universe’s changing expansion rate."
Using the James Webb Space Telescope, astronomers have captured a stunning image of a distant supernova in a galaxy that looks like it's being stretched like warm taffy.
However, the golden smear hiding this gravitationally lensed supernova, which has been nicknamed "supernova Hope," isn't just remarkable for its aesthetic value. The supernova, which exploded when the 13.8-billion-year-old universe was just around 3.5 billion years old, tells us something about a huge problem in cosmology called the "Hubble tension."
The Hubble tension comes from the fact that scientists can't agree on the exact rate of expansion of the universe, dictated by the Hubble constant. Basically, the rate can be measured starting from the local (and therefore recent) universe, then going farther back in time — or, it can be calculated starting from the distant (and therefore early) universe, then working your way up. The issue is both methods deliver values that don't agree with each other. This is where the James Web Space Telescope (JWST) comes in.
Gravitationally lensed supernovas in the early cosmos the JWST is observing could provide a third way of measuring the rate, potentially helping resolve this "Hubble trouble."
