Dark Matter, Dark Energy, Telescopes

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Canadian participation in the construction and operation of the Thirty Meter Telescope was confirmed in Prime Minister Harper’s announcement of a commitment of $243.5M towards the project. I was PI of the development grants which together with NRC matching funds built up about $35M in value for Canada in the pre-construction phase. Like other Big Science projects TMT will face a series of complex challenges as it is developed into a functioning observatory. I am a governor of the TMT International Observatory (a fiduciary position). I have begun to help organize meetings in Canada to position us for future instrumentation, continue to maintain links with our industrial partners in Canada, have the strong support of the President of the University of Toronto, and have scientific friends in all the partner countries to help Canadians work with them, which is a great opportunity for students and PDFs. Dark Energy is currently causing the expansion of the universe to accelerate. Essentially nothing is known about its physics. The Dark Energy Spectroscopic Instrument collaboration, of which I have joined as member, is building a massive new spectrograph to measure the properties of dark energy more precisely than ever before. The same data also has wide and varied uses for astrophysical investigations of the structure of the Milky Way, galaxy evolution and quasars over essentially all their entire cosmic history. Dark matter is believed to be “cold”, which means that it should be gravitationally bound into relatively low mass sub-halos orbiting in smoothed-out dark matter distribution in the halo of our own galaxy. A practical way to test for the presence of these sub-halos is to examine whether visible star-streams drawn out of globular clusters have “gaps” along their length. In the next few years the data is expected to improve dramatically and either confirm or rule out such gaps. Establishing an astronomical observatory on Ellesmere Island would have many benefits. Rather than operate observatories in other countries, it would be in ours and would give astronomers a chance to have regular contact with Canadians in the north and to communicate the excitement of science to them and help them participate more fully in Canadian universities in any field of endeavour. Our rudimentary site testing confirms the high quality of an Ellesmere site (far better than anything in southern Canada). The arctic offers the benefit of 24 hour nights, a clear, cold, dry sky for infrared observations. Although cold in the winter, it is comparable to cities like Saskatoon where Canadians work without difficulty.