JWST images

[markse68]

Good point- I suppose so Glob. I just figured that back then the universe would have been more densely packed with the elementary gases so would be more likely to collapse gravitationally into either fewer monster galaxies or more smaller ones.  But I didn't really think about time!

Mark

[Mandy D]

On 12/07/2022 at 10:36, globular said:

One HST

Customer Return

No longer required. Well used, open box.

No manufacturers warranty.

$1,500,000,000.00 $1,499,999,850.00  (saving $150.00)

Buyer to collect.

[LukeSkywatcher]

I was surprised to learn recently that all of the different coloured filters and filter wheel for the JWT were built here in Ireland, and delivered to the USA.......9 yrs ago.

They were designed in a place in Dublin.

It's nice to know the Irish contribute to space exploration. Parts of the ISS were even designed and built by the Maynooth University, in my own local town.

[IB20]

Cartwheel Galaxy

 

[maw lod qan]

The images are incredible, even with what we've come to expect from the HST.

Do you think they expected the diffraction spikes?

Can you picture Bruce Willis standing there giving his speech?

"Ah come on man, you're NASA!

You got thousands of people sitting around thinking stuff up!"

[andrew s]

1 hour ago, maw lod qan said:

Do you think they expected the diffraction spikes?

Yes they did. They will have modelled the effect of the hexagonal mirrors and the secondary support. Regards Andrew 

Edited August 2, 2022 by andrew s

[CraigT82]

There’s a nice diagram on Wikipedia showing where the diff spikes come from, it’s actually not that complicated when you see it laid out like this:

[StuartT]

it's a real shame about those diff spikes. Really detracts from the images and makes them look like advertising. Still... the JWST is not up there for aesthetic purposes, I guess

[Stu]

4 hours ago, CraigT82 said:

There’s a nice diagram on Wikipedia showing where the diff spikes come from, it’s actually not that complicated when you see it laid out like this:

Interesting. Is it me, or are the diffraction patterns rotated at 90 degrees to where they should be?

[Stu]

2 hours ago, StuartT said:

it's a real shame about those diff spikes. Really detracts from the images and makes them look like advertising. Still... the JWST is not up there for aesthetic purposes, I guess

When you look at all those red background galaxies, I don’t suppose the scientists care too much about the diff spikes.

[andrew s]

43 minutes ago, Stu said:

Interesting. Is it me, or are the diffraction patterns rotated at 90 degrees to where they should be?

I don't think so. A vertical obstruction produces a horizontal diffraction line. In reality the pattern is more complex but it shows the brightest features.

Regards Andrew 

[Stu]

8 minutes ago, andrew s said:

I don't think so. A vertical obstruction produces a horizontal diffraction line. In reality the pattern is more complex but it shows the brightest features.

Regards Andrew 

Well, as they say, everyday is a school day! Somehow that had completely passed me by until today. I always assumed the diffraction spike was in line with the vane. Not sure I can get my head around why it is  perpendicular to it but that will be for tomorrow. Thanks 👍

[wimvb]

22 hours ago, Stu said:

Well, as they say, everyday is a school day! Somehow that had completely passed me by until today. I always assumed the diffraction spike was in line with the vane. Not sure I can get my head around why it is  perpendicular to it but that will be for tomorrow. Thanks 👍

Remember the double slit experiment from school? (It also works with one narrow slit.) The slits are vertical, but the diffraction is horizontal.

[markse68]

I like the Huygens diffraction explanation- that a straight wave front is made up of an infinite number of spherical wavefronts that combine through destructive interference to create a straight wave front. If you break that front, the ends radiate spherically as they have nothing to interfere with,  causing diffraction. Something like that anyway. So a horizontal obstruction causes vertical diffraction which when focussed makes a vertical spike.

https://www.telescope-optics.net/diffraction.htm

[maw lod qan]

Thanks for the info. The team here constantly helps me learn.

Edited August 3, 2022 by maw lod qan

[Alien 13]

Regarding The JWT and its diffraction spikes does anyone know if there is a PS plugin to reproduce them as they look kind of cool 😀

Alan

[Ags]

1 hour ago, markse68 said:

I like the Huygens diffraction explanation- that a straight wave front is made up of an infinite number of spherical wavefronts that combine through destructive interference to create a straight wave front. If you break that front, the ends radiate spherically as they have nothing to interfere with,  causing diffraction. Something like that anyway. So a horizontal obstruction causes vertical diffraction which when focussed makes a vertical spike.

https://www.telescope-optics.net/diffraction.htm

My proudest mathematical moment was generating diffraction patterns using this principle despite my inability to comprehend grown up maths like Fourier transforms. Here is an animation I generated of spider vanes growing thicker.

 

Animation doesn't play on SGL 🙄

Edited August 3, 2022 by Ags

[Gfamily]

If you want to know what the JWST is looking at, you can follow it on twitter at @JWSTObservation 

It occasionally says it's observing 'None' - I think that's when it's doing calibrations. 

[CraigT82]

JWST observing Pluto and Charon, should be an interesting image…

 

[Laurieast]

On 03/08/2022 at 22:09, Alien 13 said:

Regarding The JWT and its diffraction spikes does anyone know if there is a PS plugin to reproduce them as they look kind of cool 

https://www.prodigitalsoftware.com/AstronomyToolsActions.html

[IB20]

Wonderful Neptune.

[Swoop1]

BBC report of same with wider field images-

Ringed Neptune captured by James Webb telescope - BBC News

[Elp]

This seems kind of unreal (WR140 dust shells):

https://www.bbc.co.uk/news/science-environment-63234027

 

Edited October 13, 2022 by Elp

[Gfamily]

2 hours ago, Elp said:

This seems kind of unreal (WR140 dust shells):

https://www.bbc.co.uk/news/science-environment-63234027

 

What I find interesting, is not just the rings, but the additional rays towards top-right, bottom-left and also top-left. 

They look almost like diffraction spikes, so I'd be interested to know what happens if the 'known' SPF is subtracted.  

[robin_astro]

I took part in Pro-Am studies (using spectroscopy to better define the orbit) during the wind collisions that produced the last two of those rings 🙂

https://ui.adsabs.harvard.edu/abs/2011MNRAS.418....2F/abstract

https://ui.adsabs.harvard.edu/abs/2021MNRAS.504.5221T/abstract

The next dust production episode is due November 2024

Cheers

Robin