Magellan Telescope First Mega-Mirror Polished and Ready

coondoggie writes "One of the six giant — 27 feet across, 20 ton — circular mirrors that will be part of the 4,000 sq. ft., Giant Magellan Telescope that ultimately look for stars, galaxies and black holes has been polished and completed — now for the other five. The mirrors will form the heart of the 25-meter Giant Magellan Telescope, and when complete will provide more than 380 square meters, or 4,000 square feet, of light-collecting area." This is a big project, not just a big mirror. From the article: "At the Carnegie Institution for Science's Las Campanas Observatory in northern Chile, earthmovers are completing the removal of 4 million cubic feet of rock to produce a flat platform for the telescope and its supporting buildings. The telescope is scheduled to come online in about 10 years.

Re:10 years!?!

[PerMolestiasEruditio]

in 5 years it will be obsolete, there will be yet another telescope launched into space that can see far greater distances before this is even built.

I'm wonder why anyone would even bother putting a telescope on the planet at this point, put it on the moon , no atmosphere to obstruct your view.

4 times higher resolution than James Webb, 12 times the light collecting area, 10% of the cost.

Space telescopes are only sensible for the sections of the spectrum the earth-bound just can't do.

Re:smudgy fingers

[k28]

I'm sure one of the first things that you think of when using big pieces of glass is the fact that they'll get dirty. A little bit of googling tells us that the mirrors will be regularly CO2 -cleaned, (basically blasting all dirt off the surface of the mirror) - see section 10.11: http://www.gmto.org/science-conceptu.html [gmto.org] . Each mirror will also get recoated every 2 years, to prevent scratches and blemishes.

Re:10 years!?!

[afidel]

Yeah, no kidding. The GMT has a total budget of $700M, JWST's annual budget is almost that much.