cepheid

简明释义

英[ˈsefiːɪd]美[ˈkɪfaɪd]

n. 造父变星；仙王星座的变光星

英英释义

单词用法

同义词

反义词

例句

1.Dr Learned, however, reckons the pulse-period of a Cepheid could be modulated by a suitable beam of neutrinos.

而且，伦德博士测算出“造父变星”的脉动周期能够用适当的微中子束加以调整。

2.Admittedly, the energy needed to produce a Cepheid-modulating neutrino beam really would be a sizeable fraction of the output of the sun.

应当承认，制造用来调整“造父变星”的中微子束所需要的能量确实将相当于太阳整体输出能量的大部分份额。

3.This was accomplished by observing Cepheid variables at optical wavelengths out to greater distances than obtained previously and comparing those to similar measurements from ground-based telescopes.

这是通过观测比先前远得多的造父变星的可见光谱实现的，结果与地面望远镜观测结论类似。

4.NASA Hubble Space Telescope (HST) view of the magnificent spiral galaxy NGC 4603, the most distant galaxy in which a special class of pulsating stars called Cepheid variables have been found.

哈勃太空望远镜(HST)拍摄的壮丽的漩涡星系ngc 4603，现今发现一类特殊的变星——造父变星的最远的星系。

5.On the colour-magnitude diagram they are situated near and more left than the hotter edge of the Cepheid instability stripe, so their temperature is higher than other types of pulsating variables.

在色星等图上，处于造父不稳定带的左外侧而温度较高，故简称热造父变星。

6.Another type of standard candle is a type of star called a Cepheid variable.

另一种标准烛光是一种叫做造父变星的恒星。

7.The SHOES team used Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) and the Advanced Camera for Surveys (ACS) to observe 240 Cepheid variable stars across seven galaxies.

SHOES团队使用哈勃望远镜的近红外相机和多目标光谱仪(NICMOS)、高级巡天相机(ACS)观测了综括7个星系的240颗造父变星。

8.This was accomplished by observing Cepheid variables at optical wavelengths out to greater distances than obtained previously and comparing those to similar measurements from ground-based telescopes.

这是通过观测比先前远得多的造父变星的可见光谱实现的，结果与地面望远镜观测结论类似。

9.Zhao: Boyi descendants of Cepheid, pull horse driving.

赵：伯益后裔造父，拉驯马驾车。

10.Astronomers use the brightness of a cepheid 造父变星 to measure distances to far-off galaxies.

天文学家利用造父变星的亮度来测量遥远星系的距离。

11.The discovery of cepheids 造父变星 revolutionized the field of distance measurement in astronomy.

对造父变星的发现彻底改变了天文学中距离测量的领域。

12.By studying the period-luminosity relationship of cepheids 造父变星, we can determine their intrinsic brightness.

通过研究造父变星的周期-亮度关系，我们可以确定它们的内在亮度。

13.The light curve of a cepheid 造父变星 helps scientists predict its future brightness variations.

一颗造父变星的光变曲线帮助科学家预测其未来的亮度变化。

14.Many cepheid 造父变星 are located in the Large Magellanic Cloud, providing valuable data for astronomers.

许多造父变星位于大麦哲伦云，为天文学家提供了宝贵的数据。

作文

The universe is a vast and mysterious place, filled with countless stars and galaxies, each playing a role in the grand tapestry of cosmic evolution. Among these celestial bodies, certain types of stars have fascinated astronomers for centuries due to their unique properties and significance in understanding the scale of the universe. One such type is the cepheid, which is a variable star that pulsates in brightness at regular intervals. This pulsation makes cepheids incredibly valuable for measuring astronomical distances, as their period of variation is directly related to their intrinsic luminosity.The discovery of cepheid variables dates back to the early 20th century when astronomers like Henrietta Leavitt began studying these stars in the Small Magellanic Cloud. Leavitt found a correlation between the pulsation period of cepheids and their absolute magnitude, leading to the formulation of the period-luminosity relationship. This groundbreaking work provided astronomers with a new tool for measuring distances to far-off galaxies, effectively transforming our understanding of the scale of the universe.When a cepheid star undergoes its pulsation, it expands and contracts, causing its brightness to change in a predictable manner. The longer the period of pulsation, the more luminous the star. This relationship allows astronomers to determine the distance to a cepheid by observing its brightness from Earth. By comparing the observed brightness to the intrinsic brightness calculated from its period, scientists can accurately gauge how far away the star is located. This method has been crucial in establishing the distance ladder in astronomy, enabling researchers to measure distances to galaxies millions of light-years away.The importance of cepheid variables extends beyond mere distance measurement. They also play a critical role in understanding the expansion of the universe. In the late 1990s, astronomers used cepheids to measure the rate of expansion of the universe, leading to the discovery of dark energy. This mysterious force appears to be driving the accelerated expansion of the cosmos, fundamentally altering our understanding of physics and cosmology.Moreover, the study of cepheid stars contributes to our knowledge of stellar evolution. These stars are typically found in the later stages of their life cycle, transitioning from the main sequence to the red giant phase. By examining the characteristics of cepheids, astronomers can gain insights into the processes that govern stellar evolution, including nucleosynthesis and the eventual fate of stars.In conclusion, the study of cepheid variables has profound implications for both observational astronomy and theoretical astrophysics. Their unique pulsation characteristics provide invaluable data for measuring cosmic distances and understanding the dynamics of the universe. As we continue to explore the cosmos, cepheids will undoubtedly remain a focal point of research, helping us unravel the mysteries of the universe and our place within it. The legacy of cepheid research is a testament to the power of scientific inquiry and the endless quest for knowledge that drives humanity forward.

宇宙是一个广阔而神秘的地方，充满了无数的星星和星系，每个星体在宇宙演化的宏大画卷中扮演着角色。在这些天体中，某些类型的星星因其独特的属性和在理解宇宙规模中的重要性而吸引了天文学家的注意。其中一种类型是造父变星，它是一种以规律间隔脉动亮度的变星。这种脉动使得造父变星在测量天文距离方面极为宝贵，因为它们的变化周期与其内在光度直接相关。造父变星的发现可以追溯到20世纪初，当时像亨丽埃塔·莱维特这样的天文学家开始研究小麦哲伦云中的这些星星。莱维特发现了脉动周期与绝对光度之间的相关性，从而提出了周期-光度关系。这项开创性的工作为天文学家提供了一种新的工具，用于测量遥远星系的距离，有效地改变了我们对宇宙规模的理解。当一颗造父变星经历脉动时，它会膨胀和收缩，导致其亮度以可预测的方式变化。脉动周期越长，星星越明亮。这种关系使得天文学家能够通过观察地球上造父变星的亮度来确定其距离。通过比较观察到的亮度与根据其周期计算出的内在亮度，科学家可以准确地测量这颗星星的距离。这种方法在建立天文学的距离阶梯中至关重要，使研究人员能够测量数百万光年外的星系的距离。造父变星的重要性不仅限于测距。它们在理解宇宙的扩张方面也发挥着关键作用。在1990年代末，天文学家利用造父变星测量宇宙的扩张速度，从而发现了暗能量。这种神秘的力量似乎正在推动宇宙的加速扩张，根本改变了我们对物理学和宇宙学的理解。此外，对造父变星的研究有助于我们了解恒星演化。这些星星通常出现在其生命周期的后期阶段，正从主序星转变为红巨星阶段。通过检查造父变星的特征，天文学家可以深入了解控制恒星演化的过程，包括核合成和恒星的最终命运。总之，对造父变星的研究对观测天文学和理论天体物理学都有深远的影响。它们独特的脉动特性为测量宇宙距离和理解宇宙动态提供了宝贵的数据。随着我们继续探索宇宙，造父变星无疑将继续成为研究的重点，帮助我们揭示宇宙的奥秘以及我们在其中的位置。对造父变星研究的遗产证明了科学探究的力量，以及推动人类前进的对知识的无尽追求。