Quote from: Halc
The deep field shots you see are all galaxies and no starsThere are a few nearby stars in any significant area of the sky.
The JWST Deep Field released last week was said to cover a fraction of the sky equivalent to a grain of sand held at arm's length.
- But even in this small fraction of the sky there were some individual stars, recognizable by the 6 radiating "spokes" - these are diffraction effects from the hexagonal mirrors, and the three supports for the prime focus mirror.
- This is different from galaxies, which tend to be fainter and fuzzier. Because they are fainter, the diffraction effects aren't so noticeable.
- Stars in Hubble images have "cross hairs" from the optical support structures inside Hubble, which are at right-angles.
- Looking closer at the JWST image, the stars also have some less prominent horizontal lines; I assume that these are from some other part of the optical path which has horizontal and vertical supports (like Hubble)
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