The James Webb Space Telescope has surprised scientists by unexpectedly detecting its first supernova, an explosion of a dying star. The detection could possibly open up an entirely new area of research possibilities, scientists say.
After the start of its science operations, the James Webb
Space Telescope's NIRCam camera spotted an unexpected bright object in a galaxy
called SDSS.J141930.11+5251593, some 3 to 4 billion light-years from Earth. The
bright object dimmed over a five-day period, suggesting that it could have been
a supernova, caught by sheer luck shortly after the star exploded. (The
astronomers compared the new observations with archived data from the Hubble
Space Telescope to confirm the light was new.)
Not only did James Webb spot a supernova, but astronomers
are baffled by the discovery because the telescope is not designed to find
dying stars.
The discovery is surprising as the James Webb Space
Telescope wasn't built to search for supernovas; a task usually performed by
large-scale survey telescopes that scan vast portions of the sky at short
intervals. Webb, on the other hand, looks in great detail into a very small
area of the universe.
.JPG)
|
Since the detection came already in the first week of Webb's
science operations, astronomers think that the depth of Webb's images might
actually compensate for the small area. Each deep field image includes hundreds
of galaxies — which means hundreds of opportunities to spot a supernova.
The early detection suggests the telescope might be able to
see supernovas on a regular basis that would be exciting, particularly because
Webb is expected to see the earliest galaxies that formed in the universe, in
the first hundreds of millions of years after the Big Bang. Combine that
ancient view with its unexpected supernova detection and Webb might be able to
capture the explosion of one of the first-generation stars that lit up the
universe after the dark early ages. These stars, astronomers think, had a much
simpler chemical composition than stars that were born in later epochs.
"We think that stars in the first few million years would have been primarily, almost entirely, hydrogen and helium, as opposed to the types of stars we have now," Mike Engesser, an astronomer at the Space Telescope Science Institute, which operates Webb, who led the team that announced the detection, told Inverse. "They would have been massive — 200 to 300 times the mass of our sun, and they would have definitely lived a sort of 'live fast, die young' lifestyle. Seeing these types of explosions is something we haven't really done yet."
The supernova detected marks the death of a much younger
star, one only 3 to 4 billion years old, but it's a promising start for a
telescope built to do something rather different.
Supernovas are tricky to detect since the explosion itself
lasts only a fraction of a second. The bright bubble of dust and gas that these
stellar deaths generate fades after only a few days, so a telescope needs to be
looking in the right direction at the right time to catch one.
Now astronomers must hope that Webb's first supernova wasn't
just beginner's luck.