Serbian Astronomical Journal最新文献_第2页

Did old Maya observe Mercury? 古玛雅观测到水星了吗?

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2022-01-01 DOI: 10.2298/saj211222002v

J. Vondrák, V. Böhm, B. Böhm

{"title":"Did old Maya observe Mercury?","authors":"J. Vondrák, V. Böhm, B. Böhm","doi":"10.2298/saj211222002v","DOIUrl":"https://doi.org/10.2298/saj211222002v","url":null,"abstract":"It is well known that the rich culture of old Maya contained, among other, also a very complicated and complex calendar, in which they recorded not only historical events, but also significant astronomical phenomena. Main source of information is the Dresden Codex, roughly covering the interval between 280 and 1325 AD. The problem of the so-called correlation between Mayan and our calendars (expressing the difference between Long Count of Mayan calendar and Julian date) is very old, there exist about fifty different solutions that mutually differ by up to hundreds of years. Out of these, historians mostly accept the so-called Goodman-Mart?nez-Thompson (GMT) value of 584 283 days, which is based almost entirely on historical events. On the contrary, we stressed very precisely dated astronomical data, demonstrated the contradictions of GMT with them, and derived the so-called B?hm correlation (BB) of 622 261 days, which is in excellent agreement with astronomical phenomena recorded in Dresden Codex. Maya researchers are mostly convinced that Maya did not pay much attention to Mercury. Here we conclude that the truth is opposite; we analyze the data in Dresden Codex and find many records corresponding to visibility of Mercury near its maximum elongations from the Sun, and also to their conjunctions.","PeriodicalId":48878,"journal":{"name":"Serbian Astronomical Journal","volume":"1 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68674792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Large-scale homogeneity in the distribution of quasars in the Hercules-Corona Borealis Great Wall region 大力神-北冕长城区域类星体分布的大尺度均匀性

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2022-01-01 DOI: 10.2298/saj2204029f

H. Fujii

引用次数: 0

Stellar and dust properties in a sample of blue early type galaxies 蓝色早期星系样本中的恒星和尘埃特性

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2022-01-01 DOI: 10.2298/saj2205023d

S. P. Deshmukh, N. Vagshette, M. Patil

{"title":"Stellar and dust properties in a sample of blue early type galaxies","authors":"S. P. Deshmukh, N. Vagshette, M. Patil","doi":"10.2298/saj2205023d","DOIUrl":"https://doi.org/10.2298/saj2205023d","url":null,"abstract":"This paper presents a comparative study of physical properties of a sample of 89 blue early-type galaxies (ETGs) from the local universe by fitting SEDs to their multi-wavelength photometric and spectroscopic data. The detailed template-based SED fitting analysis using the MAGPHY S and SED3FIT codes on the interstellar dust extinction corrected UV-to-far-IR spectro-photometric data enabled us to trace the evolutionary sequence of the blue ETGs on the color-magnitude diagram. This study evidenced a decreasing trend of the SFR, sSFR, dust mass, and dust mass fraction over the sequence from the SF - to - the Seyferts - to - the LINERs. The UV-optical colors also enabled us to estimate the look-back time of the last starburst phase in SF, Seyfert, and LINER galaxies, probably pointing towards the evolutionary sequence of the blue ETGs. Despite the blue colors and strong emission lines in the optical regime of the electromagnetic spectrum, the blue ETGs in the present sample occupy a position off the main sequence, commonly known as the green valley, on the CMD plot and hence indicate the transitional state of their non-secular evolution. A marginal positive correlation was noticed between SFR per unit dust mass and the temperature of the cool ISM. The declining trend of the cold dust temperature Tc over the sequence from the SF-to-Seyfert-to-LINER implies that the AGNs in the systems are not enough powerful to affect the cold component of the ISM.","PeriodicalId":48878,"journal":{"name":"Serbian Astronomical Journal","volume":"1 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68674929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Can the China's fast telescope detect extraterrestrial von-Neumann probes? 中国的快速望远镜能探测到外星冯？诺依曼探测器吗？

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2021-10-01 DOI: 10.2298/saj2103047o

Z. Osmanov

引用次数: 1

Prospects of SETI by small size optical telescopes 小型光学望远镜对SETI的展望

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2021-09-22 DOI: 10.2298/SAJ210922003O

Z. Osmanov, V. Berezhiani

引用次数: 0

BVRI photometric calibration of the Nedeljkovic telescope Nedeljkovic望远镜的BVRI光度校准

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2021-07-07 DOI: 10.2298/SAJ210404003V

A. Vudragovic, M. Jurkovic

引用次数: 0

Long-term optical photometric monitoring of the FUor star V900 Mon FUor恒星V900Mon的长期光学光度监测

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2021-05-31 DOI: 10.2298/saj2102031s

E. Semkov, S. Peneva, S. Ibryamov

{"title":"Long-term optical photometric monitoring of the FUor star V900 Mon","authors":"E. Semkov, S. Peneva, S. Ibryamov","doi":"10.2298/saj2102031s","DOIUrl":"https://doi.org/10.2298/saj2102031s","url":null,"abstract":"We present results from photometric monitoring of V900 Mon, one of the newly\u0000 discovered and still under-studied object from the FU Orionis type. The\u0000 FUor phenomenon is very rarely observed, but it is essential for stellar\u0000 evolution. Since we only know about twenty stars of this type, the study of\u0000 each new object is very important for our knowledge. Our data were obtained\u0000 in optical spectral region with the BVRI Johnson-Cousins set of filters\u0000 during the period from September 2011 to April 2021. In order to follow the\u0000 photometric history of the object, we measured its stellar magnitudes on\u0000 available plates from the Mikulski Archive for Space Telescopes. The\u0000 collected archival data suggest that the rise in brightness of V900 Mon\u0000 began after January 1989 and the outburst goes on so far. In November 2009,\u0000 when the outburst was registered, the star had already reached the level of\u0000 brightness close to the current one. Our observations indicate that during\u0000 the period 2011-2017 the stellar magnitude increased gradually in each pass\u0000 band. The observed amplitude of the outburst is about 4 magnitudes (R).\u0000 During the last three years, the increase in brightness has stopped and\u0000 there has even been a slight decline. The comparison of light curves of the\u0000 known FUor objects shows that they are very diverse and are rarely repeated.\u0000 However, the photometric data we have so far show that V900 Mon's light\u0000 curve is somewhat similar to those of V1515 Cyg and V733 Cep.","PeriodicalId":48878,"journal":{"name":"Serbian Astronomical Journal","volume":"1 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45046692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Survey of secular resonances in the asteroid belt 小行星带长期共振的调查

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2021-01-01 DOI: 10.2298/saj210903004k

Z. Knežević

{"title":"Survey of secular resonances in the asteroid belt","authors":"Z. Knežević","doi":"10.2298/saj210903004k","DOIUrl":"https://doi.org/10.2298/saj210903004k","url":null,"abstract":"Using a recently introduced synthetic method to compute the asteroid secular frequencies (Knezevic and Milani 2019), in this paper we survey the locations of secular resonances in the 9 dynamically distinct zones of the asteroid belt. Positions of all resonances up to order four, of a significant fraction of the order six resonances, and of a several order eight ones were determined, plotted in the space of proper elements, and discussed in relation to the local dynamics and to the structure and shape of the nearby asteroid collisional families. Only the resonant combinations with fundamental frequencies of Jupiter and Saturn were considered, with a few special cases involving other planets and largest asteroids. Accuracy of the polynomial fit to determine the frequencies was found to be satisfactory for the purpose of determination of secular resonance positions. This enabled a precise identification of dynamical mechanisms affecting the computation of frequencies (close vicinity of the mean motion resonances and libration in secular resonances), and of the cycle slips\" as a primary technical drawback causing deterioration of the results. For each zone we also presented and discussed a fairly complete sample of recent works dealing with interaction of the secular resonances with asteroid families present in that zone. Finally, a few words were devoted to possibilities for future work.","PeriodicalId":48878,"journal":{"name":"Serbian Astronomical Journal","volume":"1 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68675140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Investigating close binary supermassive black holes at high angular resolution 以高角分辨率研究近距离双星超大质量黑洞

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2021-01-01 DOI: 10.2298/saj2102001k

A. Kovačević

{"title":"Investigating close binary supermassive black holes at high angular resolution","authors":"A. Kovačević","doi":"10.2298/saj2102001k","DOIUrl":"https://doi.org/10.2298/saj2102001k","url":null,"abstract":"Gravitational waves (GW) in the nano-Hz domain are expected to be radiated by close-binaries of supermassive black holes (CB-SMBHs; components bound in a Keplerian binary at mutual distance less than ~ 0.1 pc), which are relicts of galaxy mergers and anticipated to be measured via the Pulsar Timing Array (PTA) technique. The challenge of present CB-SMBH investigations is that their signatures are elusive and not easily disentangled from a single SMBH. PTAs will typically have a glimpse of an early portion of the binary inspiral to catch the frequency evolution of the binary only with sufficiently high mass and initially high eccentricity. Thus, we have to make use of electromagnetic observations to determine orbital parameters of CB-SMBHs and test nano-Hz GW properties. The 2D reverberation mapping (RM) is a powerful tool for probing kinematics and geometry of ionized gas in the SMBHs (single or binary) vicinity, yet it can lose information due to projection on the line of sight of the observer. Nevertheless, spectroastrometry with AMBER, GRAVITY, and successors can provide an independent measurement of the emitting region's size, geometry, and kinematics. These two techniques combined can resolve CB-SMBHs. In this review, we focus on RM and spectroastrometry observational signatures of CB-SMBHs with non-zero eccentricity from recent simulations with particular attention to recent developments and open issues.","PeriodicalId":48878,"journal":{"name":"Serbian Astronomical Journal","volume":"1 1","pages":""},"PeriodicalIF":0.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68674706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The past, present and future of gravitational wave astronomy 引力波天文学的过去、现在和未来

IF 0.5 4区物理与天体物理

Serbian Astronomical Journal Pub Date : 2021-01-01 DOI: 10.2298/saj210518001l

H. Leverenz, M. Filipović

引用次数: 0