MRI: Development of a Deployable Tertiary Mirror for the Keck I Telescope

时域观测将成为世纪天体物理学的支柱。所有波长的宽视场成像表明，宇宙是高度动态的，在所有时间尺度上都有变化。 最令人感兴趣的是爆炸的恒星，黑洞合并，食行星，引力微透镜事件和耀斑源，这些都源于不同的天体物理过程。解决这些事件的天体物理学的核心是高精度光谱学和成像，理想情况下是在关键时刻和/或高节奏。 这样的观测需要使用大口径望远镜;但是，虽然望远镜可能拥有一套合适的仪器，但只有在每个观测夜晚都能灵活、快速地使用这些仪器，才能获得时域天体物理学的科学成果。 事实上，越来越多的宝贵的后续时间使用世界的需求？位于圣克鲁斯的加州大学的詹森·普罗查斯卡博士试图用位于西太平洋的10米直径的光学/红外凯克一号望远镜来弥补这种情况。M. Keck天文台在莫纳克亚山上的一个新的观测系统，将手动定位的三级反射镜替换为远程关节反射镜，能够在位于卡斯焦点和两个Nasmyth焦点中的任何一个上的仪器之间快速（约2分钟）切换。 如果再加上计划中的望远镜调度变化，这种技术上简单的修改不仅能够对天文事件（例如，超新星爆发、伽马射线爆发、行星撞击），而且更容易进行有节奏的观测，处理有限进入的目标，并选择最佳利用特定夜晚的仪器和观测程序？的天气条件。 这些发展将进一步提高现代天文学家可用的几乎任何衡量标准都是最具生产力和最重要的设施之一的能力，并让它继续在理解时间方面发挥重要作用-光谱仪原型的开发和建造资金由NSF的天文科学部通过其参与的主要研究仪器提供。程序.

Time-domain observations will serve as the backbone for 21st century astrophysics. Wide-field imaging at all wavelengths demonstrates that the universe is highly dynamic, with variability on all time-scales. Of great interest are exploding stars, black hole mergers, eclipsing planets, gravitational microlensing events, and flaring sources, which stem from a diverse set of astrophysical processes. Central to resolving the astrophysics of these events is high-precision spectroscopy and imaging, ideally at critical times and/or high cadence. Such observations demand the use of large-aperture telescopes; but while a telescope may possess a suite of suitable instrumentation, the scientific returns of time-domain astrophysics are only available if those instruments can be flexibly and rapidly accessed on each observing night. Indeed, the growing demands for precious follow-up time using the world?s largest telescopes conflicts with the classical approach of telescope allocation: one night, one instrument.Dr. Jason Prochaska of the University of California, Santa Cruz seeks to remedy this situation for the 10-m diameter optical/infrared Keck I telescope at the W. M. Keck Observatory atop Mauna Kea by replacing the manually positioned tertiary mirror with a remotely-articulated mirror capable of rapid (~2 minutes) switchover among the instruments that reside on the Cass focus and either of the two Nasmyth foci. When coupled with a planned change in telescope scheduling, this technologically straightforward modification will not only enable prompt response to astronomical events (e.g., supernova eruptions, gamma-ray bursts, planetary impacts), but also more easily permit cadence observing, address limited-access targets, and select the instrument and observing program which make best use of a particular night?s weather conditions. These developments will further enhance the capabilities of what is by virtually any measure one of the most productive and significant facilities available to modern-day astronomers, and allow it to continue to play a major role in understanding the time-variable universe.Funding for development and construction of the prototype spectrograph is being provided by NSF's Division of Astronomical Sciences through its participation in the Major Research Instrumentation program.