Arctic Update

By Eric Steinbring (NRC)
(Cassiopeia – Winter 2014)

A bunch of publications related to astronomy from the High Arctic have appeared in recent months, with a few follow-on news stories, which I will list here for the interested reader. Together they range along the spectrum from the submillimetre through the optical. Apart from each requiring particular innovations to make them possible (and Canadian connections) these all seem to follow a common theme. Many were presented at the SPIE “Astronomical Telescopes + Instrumentation” meeting at Montreal last summer.

Two of those reports provide descriptions of 350 GHz to 1.4 THz prototype receivers for the Greenland Telescope (GLT) [1], an ASIAA/Harvard/SAO-collaboration, and their plans for deployment and operation at Summit, near the peak of the icecap [2]. This is among the driest, lowest opacity (and most isolated) astronomical sites on Earth. When installed and completed the GLT will combine with ALMA to form the northernmost leg of the Event Horizon Telescope (EHT) for very-long-baseline interferometry; there was a nice NewsHour piece on this [3]. The truly Earth-spanning scale of EHT is necessary for an ambitious goal to directly image the gravitational “shadow” of a supermassive black hole in M87 [4].

Several papers delivered at Montreal cover developments at Eureka: the wealth of experience gained by observers from UdeSherbrooke and UQAM, within the Canadian Network for the Detection of Atmospheric Change (CANDAC), operating precise star-photometer telescopes from sea level for many years [5]; new Arctic Wide-Field Camera survey results [6] and its evolution to the “Evryscope” [7]; campaign Slope Detection and Ranging (SloDAR) turbulence profile measurements obtained at the Polar Environment Atmospheric Research Laboratory (PEARL) [8]; and a detailed description of the UofT Dunlap Institute SloDAR instrument itself [9]. Arctic-hardened designs can yield excellent photometry with reduced scintillation due to the cold, highly-stratified atmosphere. An article in the latest SkyNews points to some of these findings [10].

Finally, a concept for a cluster of small optical telescopes allowing autonomous time-domain surveys from PEARL was presented at the “Adapting to the Atmosphere” conference in September at Durham, UK [11]. The unit telescopes, each with a swappable off-the-shelf sealed-tube assembly, were given the nickname “Ukaliq” which is Inuktitut for “Arctic Hare.” There is value in duplication. Other science could profit from this approach, but one particularly good fit for Ukaliq might be a quasar lensing study employing adaptive optics; best seeing is preserved by a compact design originally intended for site testing. Again, success can come by learning to take advantage of local conditions, highlighted in a recent Universe Today post [12].

References

[1] Grimes, P.K., Asada, K., Blundell, R., et al. 2014, Instrumentation for single-dish observations with the Greenland Telescope, Proc. SPIE, 9153

[2] Raffin, P., Algaba-Marcosa, J.C., Asada, K., et al. 2014, The Greenland Telescope (GLT): antenna status and future plans, Proc. SPIE, 9145

[3] Public Broadcasting System NewsHour, How a global network of telescopes may give us first glimpse of a black hole, 25 November 2014

[4] Lu, R.-S., Broderick, A.E., Baron, F., Monnier, J.D., Fish, V.L., Doeleman, S.S., & Pankratius, V. 2014, Imaging the Supermassive Black Hole Shadow and Jet Base of M87 with the Event Horizon Telescope, ApJ, 788, 120

[5] Ivanescu, L., Baibakov, K., O’Neill, N.T., Blanchet, J.-P., Blanchard, Y., Saha, A., Rietze, M., & Schulz, K.-H. 2014, Challenges in operating an Arctic telescope, Proc. SPIE, 9145

[6] Law, N.M., Carlberg, R., Fors, O., Steinbring, E., Ngan, W., Wulfken, P., Maire, J., & Sivanandam, S., 2014, New results from the first exoplanet survey in the Canadian High Arctic, SPIE Conf. Series, 9145

[7] Law, N.M., Fors, O., Wulfken, P., Ratzloff, J., & Kavanaugh, D. 2014, The Evryscope: the first full-sky gigapixel-scale telescope, SPIE Conf. Series, 9145

[8] Maire, J., Mieda, E., Steinbring, E., Murowinski, R., Graham, J.R., Carlberg, R., Wright, S.A., Law, N.M., Sivanandam, S. 2014, Optical turbulence profiling with SloDAR in the Canadian High Arctic, Proc. SPIE, 91453

[9] Mieda, E., Maire, J., Graham, J.R., Wright, S.A., & Moon, D.-S. 2014, SloDAR instrument for characterizing an Arctic site: overview of the experimental method, design, and performance, Proc. SPIE, 9145

[10] Semeniuk, I. Arctic Telescope, SkyNews, November/December 2014

[11] Steinbring, E., Leckie, B., & Murowinski, R. 2014, Ukaliq: Seeing Long-Term with Small, Precise Arctic Telescopes, IoPCS “Adapting to the Atmosphere”, Durham UK

[12] Majaess, D. Searching for Alien Worlds and Gravitational Lenses from the Arctic, Universe Today, 24 November 2014

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