Discussion: Extremely Large Telescope Takes ...

[Fraser]

SUMMARY: Bigger is better. When you're making a telescope, you want to construct the biggest mirror you can. The European consortium building the Extremely Large Telescope (ELT) - a monster observatory with a main mirror that will be between 50-100 metres - moved a step closer to building their telescope today by releasing the scientific case. If development moves forward, the ELT could begin construction within a few years, and be complete by 2015. Where Hubble can resolve objects 95 m (311 feet) apart on the Moon, the ELT could resolve objects 2 m (6.5 feet) apart.

View full article

What do you think about this story? Post your comments below.

[antoniseb]

The total cost for this whole thing is not yet known. Anyone want to guess whether it will cost more than the Hubble Space Telescope?

[aeolus]

Originally posted by antoniseb@Jul 7 2005, 08:13 PM
The total cost for this whole thing is not yet known. Anyone want to guess whether it will cost more than the Hubble Space Telescope?

Including the assumed cost of launch and servicing?

[antoniseb]

Originally posted by aeolus@Jul 7 2005, 08:24 PM
Including the assumed cost of launch and servicing?

Yes, and while we're at it, why not adjust for inflation too, but no need to include the special servicing to correct for the badly formed mirror, as they probably won't have THAT fiasco to deal with again.

[imru]

I barely can imagine a mirror as large as they are talking about...I'm sure it would cost more than the hubble. However, we saw some amazing things with the hubble...with this kind of resolution we could be blown away yet again!

Any idea what the hubble has cost thus far?

[antoniseb]

Originally posted by imru@Jul 8 2005, 11:15 AM
Any idea what the hubble has cost thus far?

That depends on what you include in the costs, and whether you adjust for inflation. When it was launched they said it was about two billion US$. Since then they've had several Servicing missions, and some inflation. You may also want to include the cost of the new instruments, and the cost of communicating with the instrument, and staff to keep it operating (which may or may not be similar in price to the staff for ELT).

I'd guess they could build from three to thirty of the ELTs for the cost of the HST
(thirty only if there's a really big economy of scale). They might be able to build the ELT simply with the budget to upgrade and replace gyros for Hubble one more time.

[Nick4]

Sounds like a big job and an expencive one at that.

[Nereid]

THE major considerations - perfectly normal in any large budget project - are the trade-offs between cost and benefit.

In this case, the costs are fairly well constrained, but the benefits are - as in all major new science projects - essentially unknowable.

The easiest thing to do is extrapolate from what's been discovered so far (e.g. apeture vs results) to what could be discovered with a bigger instrument. That's a kind of 'minimum', in the sense that you can specify fairly well what such a big 'scope should yield, in terms of deeper imaging, better resolution, (whatever) against today's best theories, be they cosmological, planetary formation (or existence), or hum-drum astrophysics (e.g. asteroseismology).

What no one can tell you is what 'left-field' discoveries may await us - perhaps none, perhaps something that transforms human existence (most likely something in between).

If such a behemoth is actually built, work hard for a not insignificant 'Director's Discretionary Time' allocation, and an iconoclast Director.

[Guest]

Watch out as well for

Euro50, CELT, JWST, Darwin planet hunter, CalTech got a grant to design a 30-meter optical telescope, Kepler, improved-VLT, OWL.

http://www.jwst.nasa.gov/
http://www.astrosociety.org/pubs/mercury/3...3/ultimate.html
http://www.eso.org/projects/owl/Gallery.html
http://www.stsci.edu/jwst/
http://www.eso.org/outreach/info-events/ut1fl/

The total estimated cost of OWL is about 1,200 millions of Euros ( say 1,400 million US dollars ) , including 940 million Euros in capital investment. OWL will be able to reach magnitude 38 in 10 hours exposure time. This is a factor five thousand billion (5,000,000,000,000) fainter than the faintest star visible to the naked eye. OWL will be capable of imaging solar system objects at resolutions comparable to that offered by space probes