Month: January 2021

The Pinwheel Galaxy M101

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The Pinwheel Galaxy (also known as Messier 101, M101 or NGC 5457) remotely imaged by Kuldip Vora, from Ahmedabad, India.

Image:
Object: M101
DATE-OBS: 2021-01-11T22:44:46.166400
EXPTIME: 2160.00 (seconds)
SUBFRMS: 120
OBJCTRA: 14 03 13.633
OBJCTDEC: +54 20 39.20
Instrument:
Catalog: UCAC4
Bessell (B): +*.*, Bessell (V): +*.*
Bessell (R): +7.76, 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:
K.Vora, V.K.Agnihotri, B. Kumar, S. Mahawar,
Remark:
Sky Foggy and Hazy
End

Pinwheel Galaxy/Messier 101/NGC 5457)

Comet 398P/Boattini

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Image:
Object: Comet 398P/Boattini
DATE-OBS: 2021-01-06T15:17:36
EXPTIME: 3600.00 (seconds)
SUBFRMS: 30
OBJCTRA: 04 53 19.101
OBJCTDEC: +03 14 12.738
Instrument:
Catalog: UCAC4
Bessell (B): +*.*, Bessell (V): +*.*
Bessell (R): +14.6, 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:
NIL
End

Bright Star Cluster GAIA DR3

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Our friend, Willie Buning, Netherlands, provided the Gaia DR3 data within 30 Kparsec for bright star clusters (Globular as well as open clusters). The table generated by the python code developed by Joseph Karpinski. Willie modified the code a bit for plotting dominated bright star clusters in SQL or Excel. The spectral classification of stars inside clusters and their numbers presented in map. The image of Gaia DR3 map is shown below.

Useful Links

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http://simbad.u-strasbg.fr/simbad/sim-fbasic

https://aladin.u-strasbg.fr/#AladinLite

https://www.raben.com/maps/

http://lucadavino.lahost.org/blog/static.php?page=polar_finder

https://www.stsci.edu/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/calspec

https://archive.stsci.edu/hlsps/reference-atlases/cdbs/current_calspec/

https://www.techspot.com/downloads/3689-adobe-photoshop-cs2.html

http://www.rochesterastronomy.org/snimages/

http://www.cbat.eps.harvard.edu/unconf/tocp.html

https://openphdguiding.org/development-snapshots/

https://hyperion-astronomy.com/downloads/

http://skytechx.eu/?page=download

http://var2.astro.cz/ETD/protocol.php

http://www.astronomy.ohio-state.edu/asassn/transients.html

https://www.wis-tns.org/

https://www.aavso.org/

https://ascom-standards.org/

https://www.atik-cameras.com/software-downloads/

https://www.sxccd.com/support/resources/

Best Spectrophotometric Standards

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Best spectrophotometric standards:
                                      epoch  mu a cosd  mu d  Class   V Mag

LTT377         00 41 02.9  -33 44 06  1985                    f       11.2
Feige 24       02 32 30.9  +03 30 51  1950   +0.083   +0.010  DAwke   12.42
EG21           03 10 22.1  -68 39 28  1985                    DA      11.4 
G191B2B=EG247  05 01 31.5  +52 45 52  1950   +0.10    -0.0873 DAwk    11.78
GD71           05 49 34.79 +15 52 37  1950   +        -0.1898 DA1     13.03
LTT2415        05 56 24.2  -27 51 26  1985                            12.2
EG54           07 40 19.52 -17 24 41  2000  +1.136"/y -0.52"  DF      12.98 
LTT3218        08 41 33.6  -32 56 55  1985                    DA      11.8
EG63           08 47 29.6  -18 59 50  2000  -0.12"/y -0.05"/y DB      15.55
LTT3864        10 31 33.1  -35 33 03  1985                    f       12.1
Feige 34=EG71  10 36 41.1  +43 21 50  1950                    sdO     11.24
GD153          12 54 35.21 +22 18 09  1950            -0.1898 DA1     13.35
HZ 43 =EG98    13 14 00.7  +29 21 49  1950   -0.149   -0.0813 DAwk    12.91
HZ 44          13 21 19.1  +36 23 38  1950   -0.062   +0.031  sdO     11.67
EG274          16 23 33.7  -39 13 48  2000                    DA      11.0
LTT7379        18 36 26.2  -44 18 37  1985                    G0      10.2
HD 192281      20 10 46.8  +40 07 01  1950                    O5f      7.54
BD+284211=J256 21 48 57.1  +28 37 48  1950                    sdOp    10.56
LTT9239        22 52 40.88 -20 35 26  2000                    f       12.0
Feige110=EG158 23 17 23.5  -05 26 22  1950   +0.003   -0.003  sdO     11.88

OK standards:

Feige 25       02 36 00.0  +05 15 16  1950                    B6V     12.01
Hiltner 600    06 42 37.2  +02 11 25  1950                    B1V     10.42
Feige 56       12 04 13.8  +11 56 55  1950                    B5p     11.11
Feige 92       14 09 41.3  +50 21 07  1950                    Bp      11.62
BD+33 2642     15 50 02.9  +33 05 49  1950                    B2 IVp  10.88
BD+40 4032     20 06 40.0  +41 06 15  1950                    B2 III  10.45

The first set contains O stars without much Balmer absorption plus
faint southern standards from the list of Stone & Baldwin 1983, MN 204, 347.
The second set is mostly B stars that have a bit of Balmer absorption
and are usually OK.

from Link: https://www.cfa.harvard.edu/~dfabricant/huchra/standards.specp

Optical Spectroscopy of Comet C/2014 Q2 (Lovejoy) from MIRO

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Authors: Kumar Venkataramani, Satyesh Ghetiya, Shashikiran Ganesh, U. C. Joshi, Vikrant K. Agnihotri, K. S. Baliyan

Abstract: Spectra of comet C/2014 Q2 (Lovejoy) were taken with a low resolution spectrograph mounted on the 0.5 m telescope at the Mount Abu Infrared Observatory (MIRO), India during January to May 2015 covering the perihelion and post-perihelion periods. The spectra showed strong molecular emission bands (C2, C3 and CN) in January, close to perihelion. We have obtained the scale lengths for these molecules by fitting the Haser model to the observed column densities. The variation of gas production rates and production rate ratios with heliocentric distance were studied. The extent of the dust continuum using the Af-rho parameter and its variation with the heliocentric distance were also investigated. The comet is seen to become more active in the post-perihelion phase, thereby showing an asymmetric behaviour about the perihelion. 

https://arxiv.org/abs/1607.06682

Submitted 22 July, 2016; originally announced July 2016.

Comments: Accepted for publication in MNRAS

Journal ref: MNRAS 463, 2137, 2016

Optical photometry of recurrent nova M31N 2008-12a

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We report optical photometry and astrometry observation of recurrent nova M31N 2008-12a (ATel #12179, #12181, #12182) on 2018 November 7.82 UT. The observation was obtained using the 0.28m Schmidt-cassegran telescope, Cepheid’s Observatory, Rawatbhata, India. The UCAC4 and PRISMv10 Catalog are used for astrometry and photometry. The V and R band magnitudes are estimated to be 18.91 +/- 0.27 and 19.06 +/- 0.37 respectively. The coordinates for the nova is RA: 00h45m28.819s, DEC: +41°54’10.05” from astrometry. We plan to monitor this interesting nova on regular basis in coming time.

Additional BVRI photometry of recurrent nova M31N 2008-12a

We report our follow-up photometric observations of recurrent nova M31N 2008-12a. The nova brightened by ~3 mag after discovery in one day and declined back to 20-21 mag in ~ 4 days after discovery (ATels #12177, #12179, #12181, #12182, #12189, #12190, #12195, #12200, #12203). The observations were obtained using the 0.28m Schmidt-Cassegrain telescope, Cepheid’s Observatory, Rawatbhata, India. The UCAC4 and PRISMv10 Catalog are used for photometry. Nova was below the detection limit (> 19.5) in our next observations taken on 2018 November 09.77 UT .

DATE(2018)     EXP(s)   BAND     MAG
Nov 8.78 UT    1800     I     19.34 +/- 0.55
Nov 8.80 UT    1800     R    19.28 +/- 0.39
Nov 8.83 UT    1800    V    19.43 +/- 0.43
Nov 8.85 UT    1800    B    19.30 +/ -0.58

http://www.astronomerstelegram.org/?read=12189

http://www.astronomerstelegram.org/?read=12204