与春天有个约会

春天到了,万物复苏,生机渐浓,璀璨温馨的春夜星空,如约而至。人们对春天星象归结为"参横斗转(猎户座横于西天),狮子怒吼(狮子座是春季星空最为壮丽的星座),银河回家(春夜星空,银河沉于地平线之下,春不能看见),双角东守(牧夫座的大角星和室女座的角宿一,正在东方天空熠熠发光)"。本文就春季星空中的一些重要星座以及可观测天体做一个概要性的梳理,让我们与春夜星空有一个愉快的约会。     

2020年3月重要天象预告

本月天象的主角是5颗肉眼可见的行星。水星和金星将分别达到西大距和东大距;火星、木星,以及土星的可见时间都是在后半夜,其中火星将在本月下旬分别与木星和土星相合,在10天左右的时间里它们彼此之间的角距离都很小。此外,矩尺座γ流星雨也将在3月迎来极大,但它更适合在南半球观测。     

流星雨双站观测的预备计算

本文叙述了流星雨双站观测预备计算的原理,这些原理自1987年以来已在实践中应用。     

帮你建造天象馆

四川金都天仪器厂是中国兵器装备集团公司所属的专业生产天仪器的骨干军工企业。产品主要有“金都”E-6型、S-10型、S-10A型、SA-15型等天象仪系列近二十种规格,直径5～23米的天幕系列,及太阳系、流星雨等十几种附属仪器和各种天节目。     

2014年10月日、月及行星动态

木星由巨蟹座顺行至狮子座。日出时位于东南方天空,升起时间为次日凌晨约0时52分,观测条件持续好转,后半夜可见。18日12时木星合月,木星位于月亮之北5°。     

2014年12月重要天象预告

12月2日 凤凰座流星雨 12月的天象被三场流星雨主宰,首先来临的是我们几乎从没听说过,但是在今年却值得推荐的一场流星雨——凤凰座流星雨。 凤凰座流星雨是一个很奇怪又神秘的流星雨,它只在1956年12月5日爆发过一次,ZHR达到300,从那之后就销声匿迹,每年的ZHR只有1～5左右。而它的母彗星D／1819 W1（Blanpain）也只在1819年被观测到过一次。这些现象都给凤凰座流星雨蒙上了一层神秘的面纱。     

The Multi-Wavelength Quasar Survey Ⅳ. Quasars in the Leo Cluster

We aim to provide a quasar sample that is more complete than any previous surveys by using a combined selection technique to reduce the selection effects. Here we present the observational results for the X-ray candidates in the field of the Leo Cluster. We found 33 X-ray AGNs in this field of which 10 are new discoveries. The X-ray data and optical spectra of these AGNs are given. We also study the near-IR properties of the X-ray-selected AGNs by using the data from 2MASS. Most of the AGNs in our sample span the color range 0.0〈B-J〈2.5,1.0〈 J-Ks 〈2.0 and 0.5〈H-Ks〈1.2.     

The Third Peak of the 1998 Leonid Meteor Shower

1 INTRODUCTIONThe Leonid meteor shower is a well-known periodic meteor shower. Its history is tied upwith the development of the theory of meteor stream astronomy itself. It was the very st.rongshowers of 1799 and 1833 that played a sghficant pat in the recoghtion of the ealstence ofmeteoroid streams. These evellts started the obse~ions of Leoaid meteor shower and broughtabout the birth of meteoritiCS. It is known that the Leould parent comet, 55P/Tempel-TUttle,has an orbital period a…     

RT Leonis Minoris： an Unstable W Ursae Majoris System with a Spotted Component

Complete BV light curves of the W UMa type binary RT LMi are presented. From the observations, four times of minimum light were determined. Based on the new times of minimum light and those collected from the literature, changes in the orbital period of the system were found and analyzed with Kalimeris et al.'s method. The result shows that the orbital period possibly oscillates with a cycle of about 64 years and an amplitude of 1.2 × 10-6 days. The present CCD photometric observations reveal that the light curves are obviously asymmetrical, and show a positive O'Connell effect, while the light curves obtained in 1982 exhibit a negative O'Connell effect. The present light curves were analyzed by means of the latest version of the Wilson-Devinney code, which was also used to correct the photometric effects, including the distortion on the radial-velocity curves obtained by Rucinski et al. The following absolute dimensions have been derived: MI -1.28 ±0.08 M⊙, M2 = 0.48 ±0.06 M⊙, R1 = 1.28 ±0.06 R⊙,     

2012年1月重要天象预告

又是一年的天象预报与您见面了,在接下来的12期里,我很荣幸能和大家一同见证2012年精彩的天象。同时,也希望有更多朋友通过天象预报开始关注天文,进行天文观测,并能从中收获更多的快乐。2012年虽然有很多值得关注的重要天象,但一月的天象剧场并没有给大家带来眼前一亮的感觉。象限仪流星雨是全年为数不多观测会受到月光干扰的大流量流星雨,而过近日点的P／2006 T1（levy）彗星预计也不会达到肉眼可见的亮度。只是金星、火星、木星和土星这几颗经典行星的观测条件还都不错,大家可以尽情发挥,拍些行星合月的天象照片。