This week Houston businessman George Mitchell gave $25 million to the Giant Magellan Telescope, an ambitious project to build a $700 million instrument that would be the world’s largest telescope.

Mitchell’s gift provides a huge boon the ambition’s of A&M’s astronomy program, which didn’t exist a decade ago. In addition it also provides a boost to the GMT, whose developers are competing with the California-based scientists who want to build the Thirty Meter Telescope .

Both A&M and the University of Texas have a vested interest in the GMT, which would be built in Chile. It’s slightly smaller than the Thirty Meter Telescope, but both instruments are big enough that the first group to build and start using their telescope is bound to make some major discoveries.

So it’s a fund-raising race to see who can get there first.

In the wake of Mitchell’s large gift, I caught up with A&M astronomer Nick Suntzeff, who is best known for playing an important role in the discovery of dark energy.

How does this gift position A&M and Texas in terms of telescope time?

George’s gift is fantastic for A&M. It puts us about 1/3 of the way to our 10% share, which has always been my minimum goal. Last night there was a small dinner organized by UT and A&M development offices and George with possible donors. I have no idea what happened at this point. We are the second largest US partner right now in terms of $$ raised.

Does the gift put the Giant Magellan Telescope project ahead of the Thirty Meter Telescope?

We are ahead in overall funding compared to the TMT project. They raised more early capital due to the gift from the Moore foundation (it turns out the CEO of the foundation is a high school classmate. I did not know this until last month!) but we now have enough capital for the design and development phase. The next fund-raising goal is to get enough money to take us through the construction phase. I stand by the statement that our design is less expensive and less risky, and therefore we have the best chance of getting on the sky first if we raise all the money soon for the construction phase. The mirror lab has shown, by independent metrologies, that they can accurately measure the off axis mirror shape. This was the biggest hurdle in my opinion.

What sorts of new science might these large instruments discover?

It is always fun to speculate, and one is almost always wrong. The report Quarks and the Cosmos is a good start on the new physics stuff. Here are some speculations:

1. Putting much stronger limits on the time variation of fundamental constants, especially the fine structure constant and the gravitational constant. The big prize is putting limits on the constancy of the speed of light, and verifying that the gravitational force travels at the speed of light. Rather surprisingly the latter is poorly constrained.

2. Precision radial velocities at the 1 cm/s level which will allow us to measure the expansion of the Universe *directly*. that is, measure the redshift of a galaxy, wait 10 years and measure it again and see how it has changed. Everyone expects that it will be the simple result of extrapolating the present acceleration, but until you measure it…

3. Lambda CDM is not working exactly right, and we are screwing something up. It could be just the astrophysics, but it could be something else in fundamental physics, such as low acceleration non-Newtonian gravity (called by some MOND).

4. We are missing the smallest mass structures at the 10^6 solar mass level if the N-body simulations are correct. Where are they? They certainly do not seem to be visible in baryons. Maybe they are not there, which would mean that Lambda CDM has something else wrong with it. But maybe they are there. Perhaps Fermi will see gamma ray radiation from places where there are no galaxies, and with really deep images we may detect something. But how to detect a 10^6 dark matter thing baffles me right now. The only way I can see other than dark matter decay or annihilation is by the disruption of the tidal streams of stars around nearby galaxies. If physicists find the dark matter particle in the next decade, there are all sorts of observations that we can do to study the physical nature of the particle using the GMT.

5. The time variation of dark energy (and dark matter?) Some theoreticians like models where the quality of dark energy changes over time. Quintessence is such a model.

6. The scale length of dark energy. Right now we assume dark energy is homogeneous, but do we really know this? Is there an outer scale to dark energy that is less than the radius of curvature of the Universe?