An exciting potential discovery has recently rocked the world of astrophysics.
This galaxy, HD1, was just announced as the youngest, most distant galaxy ever seen.
Possessing an age of 330 million years, it’s presently 33 billion light-years away: the farthest ever seen.
This could break the old record of GN-z11: 407 million years old and 32 billion light-years distant.
If so, it’s a fascinating find: bright, luminous, and possibly home to the first truly pristine stars.
But there’s an excellent chance that HD1 is not the record-breaker it’s widely reported to be.
Yes, it’s extremely red in color, missing all of its short-wavelength light.
Only the longest-wavelength photometric filters reveal the object at all.
This is consistent with an object behind the “wall of neutral atoms” prior to reionization.
But only spectroscopy can determine a galaxy’s redshift with absolute certainty.
Multiple spectral lines, linked to quantum transitions, reveal how severely emitted light is redshifted by the expanding Universe.
For HD1, only one candidate line exists, and its detection significance is below the 5-σ threshold.
The “other” distant candidate, HD2, possesses no spectral lines at all.
Until spectroscopic confirmation arrives, caution is mandated, as no distances can be decisively determined.
Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.