Site for 42 meter telescope chosen

[astroron (Ron)]

The site for the ESO 42 meter has been chosen in Chile
http://www.eso.org/public/news/eso1018/

[M54 (Molly)]

Thanks Ron.

As I said on the alternate thread posted by Paul K, Wow! Extra solar planets observed directly!

How many years do you think it will be before it's completed?

[astroron (Ron)]

Originally Posted by M54

Thanks Ron.

As I said on the alternate thread posted by Paul K, Wow! Extra solar planets observed directly!

How many years do you think it will be before it's completed?

Hi Molly, I don't know but I have sent ESO an email to find out
Cheers

[bird (Anthony Wesley)]

In the press release linked to above it says that it will start operations in 2018.

cheers, Bird

[multiweb (Marc)]

Originally Posted by bird

In the press release linked to above it says that it will start operations in 2018.

cheers, Bird

Viewing rocky planets outside our solar system? That's exciting. You guys (planetary gurus) think it's possible with local seeing?

[adman (Adam)]

Reading the media blurb - it says that it will have better resolution than Hubble thanks to its adaptive optics....the fact that you can make adaptive optics for a 42m scope just blows my mind....

Originally Posted by multiweb

Viewing rocky planets outside our solar system? That's exciting. You guys (planetary gurus) think it's possible with local seeing?

[Satchmo]

Monolithic secondary mirror 6 meter in diameter

[multiweb (Marc)]

Originally Posted by Satchmo

Monolithic secondary mirror 6 meter in diameter

Yeah I know how that feels. Looking at Lachlan's 30'" SDM secondary (5.5") the other night at Parramatta I thought "hey! that looks like my newt primary!"

[renormalised (Carl)]

'bout time that put me obs up....told them to git me the pier installed and ready!!!

[rogerg (Roger)]

Originally Posted by adman

Reading the media blurb - it says that it will have better resolution than Hubble thanks to its adaptive optics....the fact that you can make adaptive optics for a 42m scope just blows my mind....

I think with adaptive optics they usually distort the secondary not the primary, so it's the 6m they'd be distorting here not the 42m. Still quite a challenge though, I bet.

[SkyViking (Rolf)]

Originally Posted by rogerg

I think with adaptive optics they usually distort the secondary not the primary, so it's the 6m they'd be distorting here not the 42m. Still quite a challenge though, I bet.

Actually it's the primary, at least thats what they do at VLT. But given that E-ELT's secondary is similar in size to VLT's primary then it's probably a good bet that they will apply AO to the secondary in this case. Then on the other hand it might be easier to physically distort a mirror with a larger surface - the required accuracy must be less and they can put more actuators under a larger mirror. I'm just guessing though...

I took these photos at VLT a couple of years ago. Notice how the primary is full of actuators on the back side, I thought it looked very cool
Also notice how dusty that mirror is! The reflection looks rather dull, it must have been right before its yearly resurfacing.

[astroron (Ron)]

Originally Posted by bird

In the press release linked to above it says that it will start operations in 2018.

cheers, Bird

Received a reply from ESO, they hope to have construction go ahead at the end of the year but that is not definate
They did not give me an approximate first light date

[adman (Adam)]

from the media blurb:

Five-mirror design
1 The 42-metre primary mirror collects light from the night sky and reflects it to a smaller mirror located above it.
2 The 6-metre secondary mirror reflects light back down to a still smaller mirror nestled in the primary mirror.
3 The third mirror relays light to an adaptive flat mirror directly above.
4 The adaptive mirror adjusts its shape a thousand times
a second to correct for distortions caused by atmospheric turbulence.
5 A fifth mirror, mounted on a fast-moving stage, stabilises the image and sends the light to cameras and other instruments on the stationary platform

and...

The main mirror will consist of almost 1000 hexagonal segments, each 1.4 metres across. The gain is substantial: the E-ELT will gather 15 times more light than the largest optical telescopes operating today.

not to mention...(highlighting is mine)

With its 42-metre diameter, the E-ELT will gather 15 times more light than the largest optical telescopes operating today. It will also provide images 15 times sharper than those from the Hubble Space Telescope. The E-ELT performances are thus orders of magnitude better than the currently existing facilities.

Can't wait to see those....

[bmitchell82 (Brendan)]

I was planning to build one of them in my back yard. unfortunately the olds said they didn't want it there that is one big beasty piece of kit