Consolidated grant for interim support of astronomy at Oxford

牛津大学天文学临时支持综合拨款

基本信息

批准号：
ST/J00149X/1
负责人：
James Binney
金额：
$ 52.99万
依托单位：
University of Oxford
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2012
资助国家：
英国
起止时间：
2012 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=ST%2FJ00149X%2F1
关键词：
Consolidated grant interim support astronomy

项目摘要

The proposal addresses three major themes in astronomy - to understand the origin of the Universe and the formation of galaxies, and to discover planetary systems similar to our own.All that we can see is thought to have emerged 14 gigayears ago when gravity was briefly an intensely repulsive force and blasted outwards a small region of space. After this "Big Bang", the Universe was hot, so it was full of thermal radiation. The density of this radiation was almost but not quite uniform, and the galaxies we see now owe their existence to small inhomogeneities in it. However, the clearest tracer of the primordial inhomogeneities is not the distribution of galaxies but the residual radiation field of the Big Bang, which can still be detected at radio frequencies. Consequently, for several decades astronomers have sought to measure this background radiation with ever greater precision from both the ground and space. The work proposed here is directed at improving measurements from the ground at low frequencies, where most of the detected radiation arises in our Galaxy rather than being relic radiation. Correct interpretation of data currently been taken from space by the Planck satellite requires the better knowledge of emission by our Galaxy that these ground-based measurements will provide. New technologies will also be developed to detect the earliest star formation.Astronomers have a theory of how galaxies formed. Detailed examination of our own Galaxy provides the strictest test of this theory, so major observational resources are being devoted to minutely examine of the Galaxy. Unfortunately, all observations of our Galaxy are strongly biased by our location within the system - what is near us features largely in the data, while distant objects of greater significance are overlooked. Moreover, we use different instruments, from radio telescopes to the largest optical spectrometers and special space-borne telescopes that measure the positions of stars, to measure different aspects of the Galaxy. To bring all these data data together and to understand the impact of biases on the data we need dynamical models of our Galaxy. This proposal is both to continue development of such models and to develop a new approach to fitting models to data. For the moment the models are being fitted to data from several ground-based survey programs, but towards the end of the decade data will become available from the European Space Agency's "Cornerstone Mission" Gaia, and it is vital that powerful modelling machinery is in place and thoroughly tested before then.In the last fifteen years astronomers have discovered several hundred planetary systems. The first - the easiest to detect - were very unlike the Solar System: they contained a Jupiter-like planet moving on an orbit like that of Mercury, and they revolutionised our theory of how planetary systems form. As the palette of available detection methods expands, so does the diversity of the systems being uncovered. The current consensus is that most of these systems probably formed in much the same way as the Solar System, but evolved differently in their early years. However, the theory is difficult, and its results uncertain. Therefore, the fascinating question of whether the Solar System is common or rare is best addressed by making an inventory of as many planetary systems as we can. This proposal is to fund continued work on this project. The brightnesses of thousands of stars are monitored with exquisite precision by satellites to look for tiny dips, which occur when a planet passes in front of its host star. By paying careful attention to the impact of noise, these `transits' can be used not only to discover new planets - includingones resembling the Earth - but also to study the structure and composition of their atmospheres.

该提案介绍了天文学的三个主要主题 - 了解宇宙的起源和星系的形成，并发现类似于我们自己的行星系统。我们可以看到，当重力被短暂地被强烈排斥力并炸毁了一个小空间区域时，我们可以看到的所有这些都出现了14吉维。在此“大爆炸”之后，宇宙很热，因此充满了热辐射。这种辐射的密度几乎是但并不十分统一，我们看到的星系现在归功于其中的小不均匀性。但是，原始不均匀性的最清晰的示踪剂不是星系的分布，而是大爆炸的残余辐射场的分布，这仍然可以在无线电频率下检测到。因此，数十年来，天文学家试图以地面和空间的精度更加精确地测量这种背景辐射。此处提出的工作是针对低频以从地面进行改进的，其中大多数检测到的辐射在我们的银河系中出现，而不是遗物辐射。普朗克卫星对当前从空间中获取数据的正确解释需要我们的银河系更好地了解这些基于地面的测量结果。还将开发新技术来检测最早的恒星形成。雅士运者对星系的形成方式具有理论。对我们自己的星系的详细检查提供了对该理论的最严格检验，因此主要的观察资源专门用于仔细检查银河系。不幸的是，我们对银河系的所有观察结果都对我们在系统中的位置有很大的偏见 - 数据在很大程度上是数据中的特征，而远处具有更大意义的对象则被忽略了。此外，我们使用不同的仪器，从射电望远镜到最大的光谱仪和特殊的太空传播望远镜，以测量恒星的位置，以测量星系的不同方面。为了将所有这些数据数据汇总在一起，并了解偏见对数据的影响，我们需要银河系的动态模型。该建议既要继续开发此类模型，又要开发一种将模型拟合到数据的新方法。目前，该模型已拟合到几个基于地面调查计划的数据中，但是在十年结束时，数据将从欧洲航天局的“ Cornerstone Mission” Gaia中获得，至关重要的是，在最后的十五年之前，强大的建模机械进行到位并进行了彻底的测试。第一个 - 最容易检测到的 - 与太阳系非常不同：它们包含一个像汞一样在轨道上移动的木星般的行星，他们彻底改变了我们关于行星系统如何形成的理论。随着可用检测方法的调色板的扩展，系统的多样性也随之而来。目前的共识是，这些系统中的大多数可能与太阳系的形成方式大致相同，但在早期的发展方式也有所不同。但是，该理论很困难，其结果不确定。因此，通过库存尽可能多的行星系统来解决太阳系是常见还是罕见的令人着迷的问题。该建议是为该项目的持续工作提供资金。通过卫星以精确的精度监测数千颗恒星的亮度，以寻找微小的倾角，这是当行星在其宿主恒星面前经过时发生的。通过仔细注意噪声的影响，这些“跨越”不仅可以用来发现类似于地球的新行星，还可以研究其大气的结构和组成。