Ooh, that’s a big mirror... (for the GMT)

[AKB]

Interesting article with video on casting a mirror for the GMT (Giant Magellan Telescope.)

https://spectrum.ieee.org/video/aerospace/astrophysics/casting-a-20-million-mirror-for-the-worlds-largest-telescope

 

[Helen]

I went to Arizona on a field trip with Uni (with @SimonS) a couple of years ago and we had the awesome experience of visiting the Mirror Lab and seeing/hearing about the painstaking processes involved in building these huge mirrors.  Your link brings back great memories, so thank you for posting 

Helen 

[SimonS]

@Helen got there just before me

It is a very impressive place to see. Can only handle a few mirrors at varying stages due to the sheer size. Would love to see these up close again

[Alan White]

That is indeed a big mirror, 
oddly enough you can see similarities to any mirror at the polish stage, looks like Chris Locks tile former on a bigger scale.
It also looks to take as long as his is taking in the polishing stages too.
Lockie, am I being unfair here or is it similar?

[Victor Boesen]

Aperture is king

[Alan White]

8 minutes ago, Victor Boesen said:

Aperture is king

But look at the mount required, 

that will take a heck of a lot of effort to set up on the patio! 

[Stu]

Great link, thanks. Amazing technology used to produce this, no wonder it takes so long! That's one impressive mirror support too

[Shibby]

Thankfully at F/8, it won't be too difficult to collimate. The E-ELT, however will be a right pain at F/0.93 !!

[Beulah]

2 hours ago, Shibby said:

The E-ELT, however will be a right pain at F/0.93 !!

How many coma correctors will that baby need!!

 

[barkis]

At f/.093, it is just like a Schmidt design, but I didn't see a corrector. Has to be something to drag those reflected photons into shape before they impact the sensor/s, maybe they are not plane, but curved. Vivid imagination at work here .

 

 

[Ruud]

I'm so looking forward to these new super big telescopes! Here's the GML between its predecessors and successors:

https://upload.wikimedia.org/wikipedia/commons/c/c5/Comparison_optical_telescope_primary_mirrors.svg

[TheMightyKong]

Me too.  Shame the OWL telescope got cancelled though.

[Stu]

25 minutes ago, TheMightyKong said:

Me too.  Shame the OWL telescope got cancelled though.

Didn't realize it had been, that's a shame, although hopefully these others will still provide dramatically deeper views.

Found this image on Wiki, shows just how big the aptly named OWL is compared with  some of the other large scopes built or planned.

[Ags]

I hope they uncancel OWL, and put it in space too 

[TheMightyKong]

Would have to be one helluva rocket!

[spike95609]

I'm not surprised they cancelled the Overwhelmingly Large Telescope because no matter how large a telescope is, someone can always make a bigger one, and in terms of adjectives where the hell can you go from there?

[Ags]

Overwhelmingly Large Telescope II. It works movies.

[Mr Spock]

Imagine sitting at the prime focus of one of those big ones. Oh my...

[Ags]

Exit pupil would be way too large or magnification way too high...

[Chris]

On 11/01/2018 at 15:04, Alan White said:

That is indeed a big mirror, 
oddly enough you can see similarities to any mirror at the polish stage, looks like Chris Locks tile former on a bigger scale.
It also looks to take as long as his is taking in the polishing stages too.
Lockie, am I being unfair here or is it similar?

I wish I was at the polishing stage, Alan  I'm just moving onto fine grinding with Alu oxide, however, it keeps on getting shelved as stuff crops up! (trying to go for a promotion from Radiographer to Clinical Lecturer at work at the moment, so I've got my head in books)...

Might call it the VSG telescope (Very Slow Grind telescope). The name seems to suit  

[Beulah]

43 minutes ago, Mr Spock said:

Imagine sitting at the prime focus of one of those big ones. Oh my...

If we dared to look through the OWL-T, we'd de-evolve!

[Gina]

Impressive

[Alan White]

@Lockie that name has a ring VSG telescope, like it.

Good luck with the books and potential promotion.