AI Generated Image
Hubble telescope spots 'impossible' light from a galaxy that shouldn't have been visible
Yahoo • • science
Key Points:
- Astronomers have detected ionizing ultraviolet light from an ancient galaxy, MXDFz4.4, dating back to just 250 million years after the Epoch of Reionization, using data from NASA's Hubble, JWST, and the European Southern Observatory's Very Large Telescope.
- This galaxy is unusually small—about 100 times smaller than the Milky Way—but forms stars at a rate 10 times faster, allowing it to create clear channels through surrounding gas and let ionizing light escape into intergalactic space.
- The discovery, made in October, was somewhat serendipitous and relied on a combination of extremely deep imaging and spectroscopy, confirming the galaxy's distance through its Lyman-alpha emission line.
- MXDFz4.4 is currently the earliest known galaxy to emit detectable ionizing light, shedding new light on how early galaxies may have contributed to clearing the hydrogen fog that filled the early universe.
- Researchers suggest that similar galaxies with intense star formation likely exist and played a key role in the universe’s transition from opaque to transparent during the Epoch of Reionization.
