[ExI] Webb Telescope setup going great!

[BillK]

On Thu, 17 Mar 2022 at 11:49, Brent Allsop via extropy-chat
<extropy-chat at lists.extropy.org> wrote:
>
> What about the star crosses on the image?
> Isn't that all noise, from the optics and such?
> Shouldn't it just be the star, and no cross light like that, to be a good image, without any noise?
> seems really bad to me, but then I'm clueless about such things.
>

These are called diffraction spikes. They happen when a telescope
looks at a bright light.
Wikipedia explains -
<https://en.wikipedia.org/wiki/Diffraction_spike>

The Webb is only looking at the very faint star (beyond human
eyesight) for calibration purposes.


BillK