Tango Iii: Extremely Wide-Field Observations of Transient Phenomena in the Local Universe and Solar System Patrol

The TANGO (III) project is to enable the Taiwan team to join the Zwicky TransientFacility (ZTF), which is the final part of the trilogy of the Palomar Transient Factory(PTF) led by the Caltech Astronomy. (The TANGO consortium is already a memberof the ZTF board.) Because of the experience learned from our participation inthe PTF and iPTF projects, and the readiness of the instruments (e.g., SED Machineand Robo-AO), the ZTF will have the most valuable and promising science. Forscience, we will build up a follow-up station for gravitational-wave events usingthe Lulin Observatory. For the time-series astronomy of variables and stellarphysics, we will focus on the survey for the RR Lyrae in the Galactic halo, Miravariables in the M33, the properties of Be stars in open clusters, the“gyrochronology” relation for low mass stars, and the mass transfer in eclipsingbinary systems. For the study of small solar system bodies, we will continue ourfruitful study on the analysis of asteroid light curves. Moreover, with theadvantage of the ultra-wide field of view (i.e., 47 square degree) of the ZTF, wewill initiate a new method to discover near earth asteroids of meter size. This willestablish an important understanding on the evolution of asteroid impact on theEarth and asteroid resource mining in future. ZTF will allow us to carry out themost comprehensive monitoring of the outgassing activities of comets andpossible dust coma/trail formation of asteroids. For hardware and observationalinstrument, we propose to construct a copy of the SED Machine by the InstrumentTechnology Research Center (ITRC), National Applied Research Laboratories, whichhas a strong technical base in optical instruments for industrial applications. Thisstep will promote the visibility and capability of the instrument houses in Taiwanto join cutting-edge technical projects in international collaborations. At the sametime, much more excellent scientific results are expected from the usage of theSED Machine IFU spectrograph and the Robo-AO system. Our own near-infraredcamera is now in operation at the UH88 telescope of the University of Hawaii. Thismove brings the Taiwan astronomy community to a whole new level of the opticaland near-infrared observations using medium-size telescope. The Large SynopticSurvey Telescope (LSST) will come online in 2020—2021. Because of the fundingfrom the U.S. National Science Foundation, ZTF will partly adopt the operationalmodes of LSST in its high-latitude survey and galactic plane survey between 2017and 2020. This intermediate scientific schedule will allow the TANGO team toadvance towards the frontier of time-domain astronomy in the LSST era via ZTF.