We examine the astrometry and photometry of globular star cluster M13 using Gaia EDR3 and ATLAS catalogs. The Gaia EDR3 catalog is for astrometry and ATLAS catalog is for high precession differential photometry. The software Tycho 8.0 supports both the catalogs upto +22.0 magnitudes. If stars are well resolved (imaged at higher focal length), the results will be promising.
Image: Object: M13 DATE-OBS: 2021-03-27T20:56:25.69 EXPTIME: 1320.00 (seconds) SUBFRMS: 22 OBJCTRA: 16 41 46.016 OBJCTDEC: +36 27 13.50 Instrument: Catalog: Gaia EDR3 + ATLAS Bessell (B): +*.*, Bessell (V): +*.* Bessell (R): +*.*, Bessell (I): +*.* CCD: ATIK-383L+ FILTERS: R TELESCOPE: C11, 1623.0mm PRiSMv10, Tycho Site: ORIGIN: Cepheid Observatory, India, Vorion Scientific, India SITELAT: +24:55:00:00 SITELONG:+75:33:58:99 Observers: V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora Remark: High Moon, Sky Clear. End
The offline variant, “GRAPPA”, was developed by Marc Serrau. Please also include the following acknowledgements if using the catalog in a published paper:
ESA GAIA Mission as GRAPPA3 has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium).
The acknowledgements for ALTAS catalog, to be used when publishing a paper, are as follows: This work has made use of data from the Asteroid Terrestrial-impact Last Alert System (ATLAS) project. ATLAS is primarily funded to search for near earth asteroids through NASA grants NN12AR55G, 80NSSC18K0284, and 80NSSC18K1575; byproducts of the NEO search include images and catalogs from the survey area. The ATLAS science products have been made possible through the contributions of the University of Hawaii Institute for Astronomy, the Queen’s University Belfast, the Space Telescope Science Institute, and the South African Astronomical Observatory.
References: Tonry, J.L., Denneau, L., Flewelling, H., Heinze, A.N., Onken, C.A., Smartt, S.J., Stalder, B., Weiland, H.J., Wolf, C. (2018). “The ATLAS All-Sky Stellar Reference Catalog.” Astrophys. J. 867, A105. Kostov, A., Bonev, T. (2017). “Transformation of Pan-STARRS1 gri to Stetson BVRI magnitudes. Photometry of small bodies observations.” Bulgarian Astron. J. 28, 3 (AriXiv:1706.06147v2).
Our minimal contribution appeared here!. International Churyumov readings “CAMMAC-2020”.
THE DISINTEGRATIONS OF COMETATLAS BY OBSERVATIONS IN TAJIKISTAN AND INDIA:
G.I.Kokhirova1, О.V.Ivanova2,3,4, F.Dzh.Rakhmatullaeva1,S.Borysenko3, V.K.Agnihotri5, A.M. Buriev1.1. Institute of Astrophysics of the National Academy of Sciences of Tajikistan,2. Astronomical Institute of the Slovak Academy of Sciences,3. Main astronomical observatory of the National Academy of Sciences of Ukraine,4. Astronomical Observatory named after T. ShevchenkoKyiv National University5. Cepheid Observatory, Rawabhata Via Kota,Raj, India
Long-period comet C/2019Y4 (Atlas) discovered 28 on December 2019, has passed the perihelion on May 31, 2020.At the end of March 2020, observations by the Hubble Space Telescope were registered the disintegrations ofthe comet’s nucleus into several fragments. To study the nuclear fragmentation observations of comet C/2019Y4(Atlas)in the Cepheid Observatory of India, the International Astronomical Observatory Sanglokh (IAOS)and the Hissar Astronomical Observatory (HissAO) of the Institute of Astrophysics of the National Academy of Science of Tajikistanwere out carried in March-April 2020.Some physical properties of the main nucleus fragment were evaluated using the photometric measurements of comet images.These data confirm the disintegrations of the comet’s nucleus. The coordinates of the comet were determined, the orbit was calculated.and it was shown that the disintegration of the nucleus did not affect the stability of the orbit of the main.Key words: comet, photometry, light curve, astrometry, nucleus, coordinates, orbit. Page35/36 https://cammac.univ.kiev.ua/book-of-abstracts
In March of 2021 I reached out to the Cepheid Observatory team (V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora) requesting an imaging run on asteroid Apophis. I was impressed by their effort to obtain that data, which I will use in teaching a class on Asteroid studies.
The follow on lightcurve study they performed on the data is quite interesting and is indicative of the scientific rigor of their work
Asteroid research is conducted by a small community of highly dedicated astronomers. I for one greatly appreciate the opportunity to work together with my fellow researchers on the other side of our pale blue dot. I am only just beginning my collaboration with this team of bright thinkers, and look forward to working with them in the future! Please accept my thanks for your assistance!
Jerry Hilburn(San Diego California, USA)– He is working at catfish Software Inc. and also an amateur astronomer. He is contributor in many papers on Astrometric and Photometric Measurements of double stars. For more visit:http://jdso.org/
Asteroid photometry is nothing but the study of fraction of solar radiation, which is reflected by the surface of small body. Here we examined the photometry of Apophis, a big/elongate metal rich asteroid passing by near to earth.
If we assume that asteroid Apophis is metal rich, it could reflect good part of solar radiation at V band as well as R Band. The tendency of photon reflection decrease from V (short wavelengths) to R (longer wavelengths) band. Here we took the assumption that sun is G2V type star, so most of photons are towards yellow + red end and hence small body is reflecting more photons at R band. These are just assumption to make task interesting. Anyway!
The second point is that if asteroid is perfect spherical body, spinning around random axis will reflect same flux towards telescope, but case will be different if small body have irregular structure. In this case the flux reflected will be proportional to the cosine of area seen by telescope and depend on angle between sun/asteroid/earth.
In our study, we dragged the R band flux w.r.t time. The FITS generated and examined using PriSMv10 batch photometry using UCAC4 catalog. The results are shown below.
We should not forget that Apophis photometric curve was measured w.r.t standard stars and as soon as sun and asteroid changes the position in sky, the incident solar flux does not remain constant. It can be seen that the magnitude at the end of observation goes too high.
Instrument: Catalog: UCAC4 Bessell (B): +*.*, Bessell (V): +*.* Bessell (R): +15.2, Bessell (I): +*.* CCD: ATIK-383L+ FILTERS: R TELESCOPE: C11, 1623.0mm PRiSMv10, Astrometrica Site: ORIGIN: Cepheid Observatory, India, Vorion Scientific, India SITELAT: +24:55:00:00 SITELONG:+75:33:58:99 Observers: V.K.Agnihotri, B. Kumar, S. Mahawar, K.Vora Remark: Sky Clear. End