THE THIRTY METER TELESCOPE JOSHUA THOMAS JANUARY 21 ST, 2016
THE BASICS Very large telescope (VLT) Current production is on hold awaiting further permits Based on Mauna Kea in Hawaii Thirty meter primary mirror Designed for use in visual to infrared wavelengths (310nm to 2.4microns specifically)
TELESCOPE TYPE The Thirty Meter Telescope (TMT) is planned to be a variation on the Cassegrain design Specifically a Ritchey-Chrétien type Variation which includes hyperbolic primary and secondary mirrors Also uses a third flat tertiary mirror to direct light off to the side in a nazymuth configuration
RITCHEY-CHRÉTIEN DESIGN As a Cassegrain variant the TMT contains both a concave primary mirror as well as a convex secondary mirror In this specific type however the mirrors are both hyperbolic which is designed to prevent comatic aberration There is also a elliptical tertiary mirror to direct the light to equipment off to the sides
TMT OPTICS
MIRROR SPECS 30 meter primary mirror Divided into 392 hexagonal sections allowing for mirror manipulation Focal ratio of f/1 resulting in 30m focal length Provides a total field of view of 20arcmin with 5arcmin of dimming near the edges Composed of a 2in thick non-expanding glass or ceramic
ADAPTIVE OPTICS The TMT is planned to have a Narrow Field Infrared Adaptive Optics System (NFIRAOS) This would create a laser guide star which would send instructions to the mirrors to adjust for atmospheric conditions Consists of 6 laser guide stars and 2 deformable mirrors Commissioned from NRC Canada Results in diffraction-limited viewing over a narrow field view of 10-30arcsec
RESOLUTION AND EQUIPMENT NFIRAOS would provide a resolution of 0.0055 and 0.017 for 800nm and 2.4μm wavelengths respectively This is over 10 times better then Hubble Other various instruments would allow for other types of viewing InfraRed Imaging Spectrometer (IRIS) will allow for narrow field (35 x 35 ) infrared imaging in the H, J, and K bands with high spectral resolving powers of up to 10,000
OTHER INSTRUMENTS Wide-field Optical Spectrometer (WFOS) would cover a large area of 25arcmin^2 Designed for operation in 0.31-1.1μm range High-Resolution Optical Spectrometer (HROS) has a very high resolution single object instrument with a spectral resolving power of 50,000 Planet Formation Instrument (PFI) is a possible exoplanet imager with spectroscopic capability and resolving power of >100
DESIGN HISTORY In June 2009 Mauna Kea was selected as the desired site for TMT However as the grounds of Mauna Kea contain significant cultural importance there were local protests for yet another telescope construction Initially the permit was approved however after ground-breaking began it was interrupted by protesters In Dec 2015 the court ruled the previous permit approval as invalid Currently it is unknown whether there will be more political talks on the case
SITE SELECTION There were initially 5 sites selected as candidates The board of directors narrowed this down to either Mauna Kea, Hawaii or the Atacama Desert, Chili This was concluded on based on both financial and political criteria For example the European Extremely Large Telescope (E-ELT) was currently under construction in Chili
TELESCOPE RENDERS Images courtesy www.tmt.org
TELESCOPE OPERATION TMT is planned to use different operation methods Classical Operation in which an observer and his/her team will conduct the observations themselves and time would be allotted in full or half nights Service Queue operation where a support astronomer would carry out the observations on behalf of multiple observers These methods will be used in conjunction with each other in approximately a 50-50 split
SIMULATED IMAGES Andromeda galactic nucleus with Hubble (top left) and a TMT simulation with high resolution (top right). Observations of Io with the Keck telescope and projected TMT observation (bottom).
GALACTIC AND UNIVERSAL FORMATION With advanced capability in both infrared and visual the TMT would be well suited to study of galactic formation and the interstellar medium Distribution of dark matter in forming galaxies What outside events can influence the formation of galaxies? Along with the James Webb Telescope TMT would do spectroscopic analysis towards the goal of discovering more about the early universe and when the first lights and heavy elements formed
BLACK HOLES Supermassive black holes are another topic of study for TMT Detailed observations could be made of black holes at the centers of nearby galaxies, specifically that of Andromeda This would allow for investigation on black hole activity such as binary black holes, accretion disc activity, and proper motion around the orbits of black holes
CHEMICAL ANALYSIS Being a spectroscopic telescope TMT would allow for investigation of chemical composition as well Nucleosynthesis during the big bang Chemical evolution of our own and nearby galaxies
OTHER OBJECTIVES Further measuring the Hubble constant Planet formation and primitive bodies Intergalactic medium
SOURCES CITED Thirty Meter Telescope. http://www.tmt.org/ Wikipedia. (2016). Thirty Meter Telescope. https://en.wikipedia.org/wiki/thirty_meter_telescope Franck Marchis. (2012). Monitoring Io s Insane Volcanic Activity from the Comfort of Earth. SETI Institute. http://www.seti.org/seti-institute/press-release/monitoring-io%e2%80%99s-insane-volcanic-activitycomfort-earth-0 Witze A. 2015. The Mountain Top Battle over the Thirty-Meter Telescope. Nature. 526:7571. http://www.nature.com/news/the-mountain-top-battle-over-the-thirty-meter-telescope-1.18446 Skidmore W. et al. (2015). Detailed Thirty Meter Telescope Science Case: 2015. RAA. 15:12