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1.
杨本有  张春生 《天文学报》1999,40(3):279-285,T001
1996年9月至11月间,对Hale-Bopp彗星进行了照相和光电观测,给出观测结果包括风次爆发和可能的爆发活动。  相似文献   

2.
北京天文台1 .02 .0GHz 太阳射电频谱仪从1994 年开始观测至1998 年9 月记录到太阳射电爆发171 个,2 .63 .8GHz 太阳射电频谱仪1996 年9 月投入观测至1998 年9 月,记录到146 个太阳射电爆发。1998 年4 月15 日太阳射电爆发同时在这两台频谱仪上记录到。这个事件在时间和频率上显示了丰富的幅度和结构的变化。发现了微波Ⅲ型爆发对群,并存在着丰富的快速活动现象。取得了高时间分辨率、高质量的动态谱资料,为研究耀斑各种尺度的时间及空间演化过程提供了丰富的信息。  相似文献   

3.
对云南天文台“四波段太阳射电高时间分辨率同步观测系统”自1989年12月—1994年1月期间观测到的100个射电爆发和与其共生的29个快速精细结构在日球和日面的经度分布做了统计,并做了初步的分析和讨论。  相似文献   

4.
据中国科学院北京天文台与电子工业部22所的联合观测,证认出1994年7月21日的木星十米波爆发中,有一个爆发可能是由于彗星木星碰撞引起的。  相似文献   

5.
对云南天文台“四波段太阳射电高时间分辨率同步观测系统”自1989年12月-1994年1月期间观测到的100个射电爆发和与其共生的29个快速精细结构在日球和日面的经度分布做了统计,并做了初步的分析的讨论。  相似文献   

6.
据中国科学院北京天文台与电子工业部22所的联合观测,证认出1994年7月21日的木星十米波爆发中,有一个爆发可能是由于彗星木星碰撞引起的。  相似文献   

7.
云南天文台“四波段(1.42GHz,2.13GHz,2.84GHz和4.26GHz)太阳射电高时间同步观测系统”在1990.1~1994.1期间,观测到5个具有短时标漂移结构的射电爆发事件,也就是微波Ⅲ型爆发。本文从中选取较典型的1991年3月13日事件,对Ⅲ型爆发的时间轮廓(持续时间,衰减时间)作了分析,并与米波,分米波和微波段其它观测结果作了一些比较,以求对长厘米~短分米波段(微波低端)Ⅲ型爆发的时间轮廓的特征有一个初步的了解,最后对爆发的物理参数作了估计。  相似文献   

8.
太阳二十二周峰年云南天文台四波段射电同步观测结果   总被引:1,自引:1,他引:0  
本文主要介绍云南天文台“四波段太阳射电高时间分辨率同步观测系统”1989年12月至1993年4月观测事件的统计结果,对102个射电爆发进行了初步分析,着重揭示几个类别典型事件的时间轮廓,说明射电高时间分辨率观测的意义。  相似文献   

9.
本文主要介绍云南天文台“四波段太阳射电高时间分辨率同步观测系统”(1.42,2.13,2.84和4.26GHz)1989年12月至1993年4月观测事件的统计结果,对102个射电爆发进行了初步分析,着重揭示几个类别典型事件的时间轮廓,说明射电高时间分辨率观测的意义。  相似文献   

10.
叙述了1997年1月至1998年4月,使用北京天文台7m射电望远镜在1-2GHz频率上观测的微波Ⅲ型爆发的分析结果.共分析60个事件,获得了单峰、多峰、群集和负吸收微波Ⅲ型爆发的四种型别.通过对它们的频宽、频漂、偏振等重要参量的分析,初步得出微波Ⅲ型爆发在1-2GHz上的一些基本特性.  相似文献   

11.
通过对活动区NOAA 6891中三个X级耀斑前后的向量磁场分析 ,研究耀斑发生条件与耀斑发生前后横向磁场和磁剪切变化的关系。我们发现与Hagyard的耀斑发生条件不同的是 ,强的横向磁场和磁剪切不是活动区中耀斑发生的充要条件。我们的结果表明 ,活动区NOAA 6891 1 991年 30日的耀斑发生在横向磁场和磁剪切剧烈下降后。尽管 1 0月 2 7日的耀斑发生后横向磁场和磁剪切变化很大 ,但由于有新磁流浮现 ,造成磁中性线的改变 ,使得横向磁场和磁剪切变化与耀斑发生的联系变得比较复杂。  相似文献   

12.
Two events of outburst of Garnet Hale - Bopp occurred on Oct. 9,1996 and Nov. 13,1996 are observed by means of photoelectric integrating photometer mounted on the 60cm reflector of Purple Mountain Observatory. The results are shown in Tab. 3, Fig. 1 (Oct. 9, 1996) and in Tab.4,Fig.2(Nov.13,1996).  相似文献   

13.
Hoyt & Schatten (1998) claim that Simon Marius would have observed the sun from 1617 Jun 7 to 1618 Dec 31 (Gregorian calendar) all days, except three short gaps in 1618, but would never have detected a sunspot – based on a quotation from Marius in Wolf (1857), but mis‐interpreted by Hoyt & Schatten. Marius himself specified in early 1619 that for one and a half year... rather few or more often no spots could be detected... which was never observed before (Marius 1619). The generic statement by Marius can be interpreted such that the active day fraction was below 0.5 (but not zero) from fall 1617 to spring 1619 and that it was 1 before fall 1617 (since August 1611). Hoyt & Schatten cite Zinner (1952), who referred to Zinner (1942), where observing dates by Marius since 1611 are given but which were not used by Hoyt & Schatten. We present all relevant texts from Marius where he clearly stated that he observed many spots in different form on and since 1611 Aug 3 (Julian) = Aug 13 (Greg.) (on the first day together with Ahasverus Schmidnerus); 14 spots on 1612 May 30 (Julian) = Jun 9 (Greg.), which is consistent with drawings by Galilei and Jungius for that day, the latter is shown here for the first time; at least one spot on 1611 Oct 3 and/or 11 (Julian), i.e. Oct 13 and/or 21 (Greg.), when he changed his sunspot observing technique; he also mentioned that he has drawn sunspots for 1611 Nov 17 (Julian) = Nov 27 (Greg.); in addition to those clearly datable detections, there is evidence in the texts for regular observations. For all the information that can be compared to other observers, the data from Marius could be confirmed, so that his texts are highly credible. We also correct several shortcomings or apparent errors in the database by Hoyt & Schatten (1998) regarding 1612 (Harriot), 1615 (Saxonius, Tard´e), 1616 (Tard´e), 1617–1619 (Marius, Riccioli/Argoli), and Malapert (for 1618, 1620, and 1621). Furthermore, Schmidnerus, Cysat, David & Johann Fabricius, Tanner, Perovius, Argoli, and Wely are not mentioned as observers for 1611, 1612, 1618, 1620, and 1621 in Hoyt & Schatten. Marius and Schmidnerus are among the earliest datable telescopic sunspot observers (1611 Aug 3, Julian), namely after Harriot, the two Fabricius (father and son), Scheiner, and Cysat. Sunspots records by Malapert from 1618 to 1621 show that the last low‐latitude spot was seen in Dec 1620, while the first high‐latitude spots were noticed in June and Oct 1620, so that the Schwabe cycle turnover (minimum) took place around that time, which is also consistent with the sunspot trend mentioned by Marius and with naked‐eye spots and likely true aurorae. We consider discrepancies in the Hoyt & Schatten (1998) systematics, we compile the active day fractions for the 1610s, and we critically discuss very recent publications on Marius which include the following Maunder Minimum. Our work should be seen as a call to go back to the historical sources. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

14.
The results of photographic observations of Comet Hale-Bopp made at Qingdao Station of Purple Mountain Observatory during the period from September to November of 1996 are given. It is shown that three events of outburst occurred on Sept. 24, Oct. 26 and Nov. 13, and a large jet appeared in the plate of Sept.23,1996.  相似文献   

15.
The peculiar nova-like star PU Vul was observed spectroscopically from 1981 Sept 12 to 1983 Dec 11 at Yunnan Observatory and Beijing Observatory. In 1981 Sept, the star showed an absorption spectrum of the Balmer lines, the H,K and D lines, and some FeII, SrII and TiII lines. H was seen in emission in 1982 Oct and Hβ, in 1983 Sept. Both emissions were enhanced in 1983 Oct. and then dimmed since 1983 Nov. On 1983 Dec 11, Hβ might be absent, but the H was still visible. The spectral type was similar to that of an F giant during this period. This object may be an exceptionally slow nova and a binary consisting of an M giant and a hot companion.  相似文献   

16.
The list of mass ejections published in Solar Geophysical Data during the period of Jan. 1981 to Oct. 1987 contains about 1300 Surges, Sprays and Type II bursts. The relationship between the mass ejection events and the shock front events is investigated by means of correlation of time and position. The result shows that type II bursts start as frequently after the mass ejections as prior to them.  相似文献   

17.
程凌翔  李惕碚 《天文学报》1994,35(1):109-112
脉冲星PSR1951+32的X射线脉冲辐射程凌翔,李惕碚,孙学军,马宇蒨,吴枚(中国科学院高能物理研究所,北京100039)主题词:脉冲星-X射线源1987年6月,用频率387MHz的射电观测发现了脉冲星PSR1951+32[1],同年7月,在180...  相似文献   

18.
According to the data of fast UBVRI photometry of the red flaring dwarf star EV Lac obtained in the course of international cooperative observations, a fine temporal structure of two large flares (15 Oct 1996 and 10 Oct 1998) with amplitudes of 3.73 and 2.72 magnitudes in the U band have been studied. A detailed colorimetric analysis allowed us to trace variations in the flare plasma characteristics such as the optical thickness, electron density, and temperature during the development of the flare. It was revealed that, in the time period up to the maximum brightness, both flares are in the state of hydrogen plasma, which is optically thin in the Balmer continuum. In the region of the brightness maximum, both flares emit for about 1 min as an absolutely black body (ABB), the temperature of which varies from 20000 to 12000 K and 16000 to 14000 K, respectively. Then, these flares pass to the plasma state, is optically thick in the Balmer continuum. At the brightness maximum, the flares emitted as an ABB with a temperature of about 15000 and 16000 K. In the ABB approximation, the linear sizes of the flares are approximately 5 and 3% of the stellar radius at luminosity maximum. The area is 5.1 × 1018 cm2 and 1.6 × 1018 cm2.  相似文献   

19.
1974年10月11日耀斑的光谱分析表明,连续发射和微波爆发几乎同时达到极大。在连续辐射极大时刻出现了高项巴耳末发射线和微弱的巴耳末跳跃,所有这些说明这个耀斑是I型白光耀斑。我们发现,在这个耀斑连续发射的极大时刻,CaIIK线的K1处强度大大增强,约达到连续辐射强度的一半,对应的辐射温度达到5716K。这个反常增强的持续时间小于4分钟。现有的半经验模型似不能给出这样的结果。色球压缩区也不能给出解释  相似文献   

20.
The proper motion of the faint (V = 25.6 mag) neutron star RXJ1856.5‐3754 as measured consistently with both the FORS1 optical imager on the ESO Very Large Telescope (VLT) as well as with the ROSAT High Resolution Imager is presented. With two VLT images obtained with a 0.95 year epoch difference in Apr 1999 and Apr 2000, a proper motion of μα = 0.326 ± 0.064″ per year to the east and no detectable motion in declination is found, consistent with simultaneous findings by Walter (2001) using three HST observations. Also, by comparing the positional differences between the strong X‐ray source RXJ1856.5‐3754 and other X‐ray sources detected in the same ROSAT High Resolution Imager field (observed in Oct 1994 and Oct 1997), a proper motion of 0.34 ± 0.12″ to the east is detected. This may be the first star, where a proper motion is clearly detected in X‐ray images. Additional VLT images taken in half‐year intervals give an upper limit to the parallax of ∼51 mas. Furthermore, in archived VLT observations, the first B‐band detection of this object is found with B = 25.14 ± 0.41 mag.  相似文献   

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