Exploratory Search for Extrasolar Trojan Planets in Binary Systems

在过去的几年里，人们在其他恒星周围发现了许多行星。这些发现中的大多数都是使用最近开发的高精度光谱技术完成的。文献中还提出了其他方法，这些方法是基于通过行星凌日来探测母恒星的一些光的日食。观测大群恒星的研究正在进行中，希望能观测到一次日食。然而，这取决于某些行星的轨道平面指向地球，以及观测系统时发生的日食。在这个项目中，寻找行星的方法将是选择更有可能在轨道平面上有地球的行星，并选择发生在我们可能能够大致预测的时间的日食。轨道排列的优化将通过观察与地球成对运行的双星系统恒星靠近轨道平面来实现，正如我们对周期性日食的观测所表明的那样。这个项目的风险和探索性性质是假设行星可能有形成并停留在实际恒星轨道上的特殊稳定点的趋势，如果没有其他摄动体，它们可能会留在那里。这导致了可预测的行星食时间相对于恒星食时间。虽然限制三体问题的理论在特洛伊小行星的显著发现中得到了验证，但在其他恒星系统中还没有这种类型的例子。一些日食双星将被系统地监测，以寻找由于系统中的“特洛伊行星”凌日而产生的微妙的光食。测量将通过每个系统同一轨道阶段的多次观测获得，数据将从所有观测中求平均，以减少观测噪声。初步实验表明，应该有可能探测到由比木星大的行星引起的亮度千变万化。通过观测仙后座V442获得的数据中的早期结果暗示了探测的可能性。将使用的设施和设备是以前由国家科学基金会资助的。该项目将让本科生和研究生参与数据的获取、分析和发布。这是美国国家科学基金会在阿巴拉契亚州立大学暗天天文台天文学项目中支持的第一个重大研究项目。该项目由天文科学部资助。

AST-0089248CatonIn the last few years a number of planets have been discovered around other stars. Most of these discoveries have been made using recently developed high precision spectroscopic techniques. Other methods, based on detecting eclipses of some of the light of the parent stars by transits of a planet, have been suggested in the literature. Studies are under way to look at large groups of stars with the hope of observing an eclipse. However, this depends on some of the planets having their orbital plane "pointed" at the Earth and the eclipse occurring when the system is being observed.In this project, the search for planets will be optimized by choosing stars more likely to have planets with the Earth in their orbital plane and with eclipses that occur at times that we may be able to approximately predict. The optimization of the orbital alignment will be achieved by looking at eclipsing binary system stars orbiting in pairs with the Earth close to the orbital plane, as indicated by our observations of periodic eclipses.The risky, exploratory nature of this project is the supposition that the planets may have a tendency to form and stay at special points of stability in the actual stellar orbits where, if there are no other perturbing bodies, they may remain. This leads to predictable planetary eclipse times with respect to the stellar eclipse times. While the theory of the restricted three-body problem was verified with the remarkable discovery of the Trojan asteroids, no examples of this type in other star systems are yet known to exist.A number of eclipsing binary stars will be systematically monitored to search for subtle eclipses of the light due to transits of "Trojan planets" in the system. Measurements will be obtained from observations of several passes across the same orbital phase for each system, and the data will be averaged from all the observations to reduce the observational noise. Initial experiments have shown that it should be possible to detect millimagnitude changes in brightness caused by planets larger than Jupiter. Early results in the data obtained by observing V442 Cassiopeia hint at the possibility of a detection.The facilities and equipment to be used were obtained by previous funding from the National Science Foundation. The project will involve undergraduate and graduate students in the acquisition, analysis, and publication of the data. This is the first major NSF supported research project in the astronomy program at the Appalachian State University's Dark Sky Observatory.This project is funded by the Division of Astronomical Sciences.***