Issue 2 • July, 2006
Thirty Meter Telescope

Focus on... Site Testing

For a telescope as ambitious as TMT, a great site has to be selected. The data we are collecting on the astronomy performance of our candidate sites is now good enough that we are learning a great deal from it. An internal quarterly review of site testing data, just conducted, now shows how good our five candidate sites are. They are all remarkably good, but they are different in significant ways.

Choosing a site for TMT is actually quite complex. We are learning this as we analyze the data. You might guess that you can specify in advance how to use the site testing data to rank the sites. It is not so simple. There are several qualities related to astronomy observing, and some sites are excellent in some, and offer less in others. The challenge is to choose a site that will facilitate all of the kinds of science observations that TMT can perform over several decades.


Project Manager's Corner: Our Owners Meet

A great telescope captures the public mind. When I travel and meet a stranger on an airplane and tell them what I am working on, the almost invariable reaction is fascination. To look into the farthest and oldest reaches of the Universe, to spy on the birth and death of stars, to uncover a hint of a planet around a distant sun, is high romance and wonder. And to design and build the giant instrument that makes this possible is an adventure in itself.

Telescopes have been built by private initiative. They have also been built by public funding. These initiatives have been stimulated by high public interest and wonder. The public owns the telescope through its excitement. A great telescope is a public trust.


Science Nugget—Charting Cosmic Reionization with TMT

The reionization of the intergalactic medium about 13 billion years ago was a landmark event in cosmic history. It brought the so-called “Dark Ages” to a close and rendered space transparent to ultraviolet photons. Essentially, it marks the beginning of the Universe that appears familiar to us today.

When did this remarkable event happen? What role did the first star-forming galaxies play and how did those early systems develop to become the galaxies we see at later times? These questions represent the final frontier in understanding the origin of stellar systems where current facilities are finding it very hard to make further progress.

TMT is just one of several future astronomy facilities that promise to enable great discoveries at early cosmic times. The successor to Hubble, the James Webb Space Telescope (JWST), is designed to image to unprecedented flux limits, and a variety of radio facilities will chart the spatial distribution of neutral hydrogen using the redshifted 21-centimeter line. How will TMT interface with such facilities and what will be its unique role?


Technology Nugget—SODAR: TMT’s Bat in the Night

It’s dark. Too dark to see. And yet as it flies through the night hunting for its first prey, a bat makes no mistake and dives with opened jaw right into an unsuspecting moth. If you take a close look at a bat, it is obvious that the animal does not rely on its tiny eyes to see in the dark. In some species, the eyes are even hard to find. What you won’t have problems finding, however, are its ears. Sometimes several time the size of its head, a bat’s ears are clearly its main navigation system. As it flies, a bat emits ultrasounds that reflect off solid surfaces like trees or insects. Listening to sound reflections, the bat can build a map of its surrounding without using its eyes.

This amazing technique led to one of the best examples of science borrowing from nature. In 1906, Lewis Nixon used it to detect icebergs. Like a bat in the night, it is not possible to see very far through water and so the SONAR was born. This term, meaning SOund NAvigation and Ranging, was first coined during World War II when SONARs were the only way to detect submarines.


Q&A with Jerry Nelson

Astronomer Jerry Nelson of the University of California Observatories/Lick Observatory at UC Santa Cruz is the Project Scientist for the Thirty Meter Telescope.

Jerry brings great experience as the principal designer and project scientist for the world’s largest optical telescopes, the twin W. M. Keck telescopes on Mauna Kea, Hawaii, to his job with TMT, including recent work on Keck’s state-of-the-art adaptive optics systems.

Jerry received his B.S. in physics from the California Institute of Technology and his Ph.D. in elementary particle physics from UC Berkeley. He has earned numerous honors for his work on the Keck Telescopes. Jerry spoke recently with Warren Skidmore about the challenges and opportunities of the TMT project.

Download Jerry Nelson interview
[26 min. 24 MB MP3]

Around the Community

The European Southern Observatory (ESO) has taken an important step toward the realization of a new giant telescope for Europe’s astronomers by creating the ESO Extremely Large Telescope (ELT) Project Office, headed by Jason Spyromilio, the former director of La Silla Paranal Observatory.

"We believe that the European Extremely Large Telescope (E-ELT) is essential if we are to ensure the continued competitiveness of the astronomical community in ESO’s member-states," said ESO Director General Catherine Cesarsky, in a July 20 press release. "This goal can be achieved in a timely manner through ESO and the community working closely together, and the establishment of the ELT project office is a significant step in this direction."

The ESO ELT Project Office, part of the ESO Telescope Systems Division, will work closely with experts from both ESO and the European scientific community via an ELT science and engineering working group, and a standing review committee established by the ESO Council, as well as with other ELT projects, including regular consultation with the TMT project.

A baseline design for the E-ELT is scheduled to be presented to the ESO Council at the end of 2006, based on a telescope with a primary mirror between 30-60 meters in diameter and a financial envelope of about 750 million Euros.

TMT "In The News"

Recent articles mentioning TMT in the popular media:

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You have received this issue of the TMT Newscast because of your previous professional contact with the Thirty Meter Telescope Project, the Association of Universities for Research in Astronomy (AURA) Inc., the California Institute of Technology, the University of California, or the Association of Canadian Universities for Research in Astronomy (ACURA).

TMT is supported in the United States by the Gordon and Betty Moore Foundation and the US National Science Foundation. Canadian funding is provided by the Canada Foundation for Innovation, the Ontario Ministry of Research and Innovation, the National Research Council of Canada, the Natural Sciences and Engineering Research Council, and the British Columbia Knowledge Development Fund.

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