Jump to content

Banner2.jpg.35fd74882a15b2b8a1b4142f7dcc8bed.jpg

JWST images


IB20
 Share

Recommended Posts

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

Link to comment
Share on other sites

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.

  • Like 2
Link to comment
Share on other sites

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.

  • Like 3
Link to comment
Share on other sites

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!"

Link to comment
Share on other sites

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 by andrew s
  • Like 1
Link to comment
Share on other sites

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

Link to comment
Share on other sites

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:

image.thumb.png.60e8bd8a933aa17b9aae27fb672019ab.png

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

  • Like 1
Link to comment
Share on other sites

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.

  • Like 4
  • Haha 1
Link to comment
Share on other sites

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 

Link to comment
Share on other sites

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 👍

Link to comment
Share on other sites

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.

  • Like 1
Link to comment
Share on other sites

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

  • Like 1
Link to comment
Share on other sites

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.

image.png.f04dd260ba0683f24ac192db2f5f188f.png

 

Animation doesn't play on SGL 🙄

Edited by Ags
Link to comment
Share on other sites

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. 

  • Like 2
Link to comment
Share on other sites

  • 1 month later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.