Gamma-ray Burst 170121B

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 21 Jan 17 14:44:46 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      46
TRIGGER_NUM:     506702667
GRB_RA:           78.200d {+05h 12m 48s} (J2000),
                  78.419d {+05h 13m 41s} (current),
                  77.558d {+05h 10m 14s} (1950)
GRB_DEC:          +0.383d {+00d 22' 60"} (J2000),
                  +0.403d {+00d 24' 09"} (current),
                  +0.325d {+00d 19' 29"} (1950)
GRB_ERROR:       17.28 [deg radius, statistical plus systematic]
GRB_INTEN:       116 [cnts/sec]
DATA_SIGNIF:     7.50 [sigma]
INTEG_TIME:      2.048 [sec]
GRB_DATE:        17774 TJD;    21 DOY;   17/01/21
GRB_TIME:        53062.41 SOD {14:44:22.41} UT
GRB_PHI:         122.00 [deg]
GRB_THETA:        60.00 [deg]
DATA_TIME_SCALE: 2.0480 [sec]
HARD_RATIO:      0.77
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   3%  GRO_J0422_32
DETECTORS:       0,0,0, 0,1,0, 0,0,0, 1,0,0, 0,0,
SUN_POSTN:       304.01d {+20h 16m 02s}  -19.77d {-19d 45' 58"}
SUN_DIST:        131.37 [deg]   Sun_angle= -9.0 [hr] (East of Sun)
MOON_POSTN:      228.99d {+15h 15m 59s}  -12.88d {-12d 53' 00"}
MOON_DIST:       148.28 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      200.75,-21.61 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       77.21,-22.53 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170121614/quicklook/glg_lc_medres34_bn170121614.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 109.35,4.42 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 21 Jan 17 14:44:56 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      58
TRIGGER_NUM:     506702667
GRB_RA:           75.400d {+05h 01m 36s} (J2000),
                  75.613d {+05h 02m 27s} (current),
                  74.777d {+04h 59m 06s} (1950)
GRB_DEC:          -3.667d {-03d 40' 00"} (J2000),
                  -3.643d {-03d 38' 34"} (current),
                  -3.738d {-03d 44' 17"} (1950)
GRB_ERROR:       7.70 [deg radius, statistical plus systematic]
GRB_INTEN:       335 [cnts/sec]
DATA_SIGNIF:     28.70 [sigma]
INTEG_TIME:      4.096 [sec]
GRB_DATE:        17774 TJD;    21 DOY;   17/01/21
GRB_TIME:        53062.41 SOD {14:44:22.41} UT
GRB_PHI:         122.00 [deg]
GRB_THETA:        65.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO:      0.65
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      94%  GRB
2nd_MOST_LIKELY:   3%  Generic Transient
DETECTORS:       0,0,0, 0,1,0, 0,0,0, 1,0,0, 0,0,
SUN_POSTN:       304.01d {+20h 16m 02s}  -19.77d {-19d 45' 58"}
SUN_DIST:        127.02 [deg]   Sun_angle= -8.8 [hr] (East of Sun)
MOON_POSTN:      229.00d {+15h 15m 59s}  -12.88d {-12d 53' 00"}
MOON_DIST:       148.82 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      203.13,-26.02 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       73.71,-26.28 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170121614/quicklook/glg_lc_medres34_bn170121614.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 109.35,4.42 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 21 Jan 17 14:45:00 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      57
TRIGGER_NUM:     506702667
GRB_RA:           70.920d {+04h 43m 41s} (J2000),
                  71.124d {+04h 44m 30s} (current),
                  70.322d {+04h 41m 17s} (1950)
GRB_DEC:          -9.180d {-09d 10' 47"} (J2000),
                  -9.149d {-09d 08' 56"} (current),
                  -9.272d {-09d 16' 20"} (1950)
GRB_ERROR:       3.14 [deg radius, statistical only]
DATA_SIGNIF:     22.50 [sigma]
DATA_INTERVAL:   4.096 [sec]
GRB_DATE:        17774 TJD;    21 DOY;   17/01/21
GRB_TIME:        53062.41 SOD {14:44:22.41} UT
GRB_PHI:         121.00 [deg]
GRB_THETA:        72.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:       304.01d {+20h 16m 02s}  -19.77d {-19d 45' 58"}
SUN_DIST:        120.46 [deg]   Sun_angle= -8.5 [hr] (East of Sun)
MOON_POSTN:      229.00d {+15h 15m 59s}  -12.88d {-12d 53' 01"}
MOON_DIST:       148.88 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      206.38,-32.52 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       67.84,-31.16 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170121614/quicklook/glg_lc_medres34_bn170121614.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_506702667.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 21 Jan 17 14:45:41 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      1
TRIGGER_NUM:     506702667
GRB_RA:           67.460d {+04h 29m 50s} (J2000),
                  67.664d {+04h 30m 39s} (current),
                  66.862d {+04h 27m 27s} (1950)
GRB_DEC:          -9.350d {-09d 20' 59"} (J2000),
                  -9.314d {-09d 18' 49"} (current),
                  -9.458d {-09d 27' 28"} (1950)
GRB_ERROR:       1.80 [deg radius, statistical only]
DATA_SIGNIF:     22.00 [sigma]
DATA_INTERVAL:   9.216 [sec]
GRB_DATE:        17774 TJD;    21 DOY;   17/01/21
GRB_TIME:        53062.41 SOD {14:44:22.41} UT
GRB_PHI:         118.00 [deg]
GRB_THETA:        74.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41531 (Gnd S/W Version number)
SUN_POSTN:       304.01d {+20h 16m 02s}  -19.77d {-19d 45' 57"}
SUN_DIST:        117.38 [deg]   Sun_angle= -8.2 [hr] (East of Sun)
MOON_POSTN:      229.00d {+15h 16m 00s}  -12.89d {-12d 53' 06"}
MOON_DIST:       151.08 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      204.72,-35.65 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       63.88,-30.77 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170121614/quicklook/glg_lc_medres34_bn170121614.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_506702667.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This is likely a Long GRB.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(0.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=7668).

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 21 Jan 17 14:45:59 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      3
TRIGGER_NUM:     506702667
GRB_RA:           71.740d {+04h 46m 58s} (J2000),
                  71.943d {+04h 47m 46s} (current),
                  71.145d {+04h 44m 35s} (1950)
GRB_DEC:          -9.700d {-09d 41' 59"} (J2000),
                  -9.670d {-09d 40' 12"} (current),
                  -9.789d {-09d 47' 18"} (1950)
GRB_ERROR:       1.00 [deg radius, statistical only]
DATA_SIGNIF:     48.10 [sigma]
DATA_INTERVAL:   15.360 [sec]
GRB_DATE:        17774 TJD;    21 DOY;   17/01/21
GRB_TIME:        53062.41 SOD {14:44:22.41} UT
GRB_PHI:         122.00 [deg]
GRB_THETA:        72.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41531 (Gnd S/W Version number)
SUN_POSTN:       304.01d {+20h 16m 02s}  -19.77d {-19d 45' 57"}
SUN_DIST:        120.90 [deg]   Sun_angle= -8.5 [hr] (East of Sun)
MOON_POSTN:      229.00d {+15h 16m 01s}  -12.89d {-12d 53' 08"}
MOON_DIST:       147.94 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      207.36,-32.02 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       68.69,-31.80 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170121614/quicklook/glg_lc_medres34_bn170121614.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_506702667.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        This is likely a Long GRB.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.  
COMMENTS:           
COMMENTS:        NOTE: This GBM event is temporally(0.0<100sec) coincident with the INTEGRAL_SPIACS event (trignum=7668).

GCN Circular #20502
V. Lipunov, E. Gorbovskoy, E.Popova, N.Tyurina, V.Kornilov, D.Kuvshinov, N.Tyurina, A.V.Krylov, I.Gorbunov, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D.Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institut of MSU
V.Yurkov, Yu.Sergienko Blagoveschensk Educational State University, Blagoveschensk
K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk, O. Ershova Irkutsk State University
A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
R.Podesta, C.Lopez, F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) , National University of San Juan, Argentina
H. Levato, C. Saffe Instituto de Ciencias Astronomicas,de la Tierra y del Espacio (ICATE), San Juan, Argentina
D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Blagoveschensk was pointed to the Fermi trigger Number 506702667 72 sec after notice time and 171 sec after trigger time at 2017-01-21 14:47:14 UT.
MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 04h 50m 17.73s -09d 16m 02.0s . The OT unfiltered magnitude is 14.9m (limit 16.0 m).
The OT is seen in 5 images. OT detected before maximum and shown decay on last images 4 minutes after detection.
We have reference image without OT on 2017-01-21.61560 UT with unfiltered magnitude limit 20.5 m.
Spectral observations are required.
The message may be cited.
GCN Circular #20504
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a ToO observation of the Fermi/GBM GRB 170121B. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/ToO_GRBs/00020729
Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. These are not necessarily related to the Fermi/GBM event. Any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration.
Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).
This circular is an official product of the Swift-XRT team.
GCN Circular #20505
R. Hamburg (UAH), C. Meegan (UAH), and P. Veres (UAH) report on behalf of the Fermi GBM Team:
"At 14:44:22.41 UT on 21 January 2017, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 160121B (trigger 506702667 / 170121614).
It may be noted that this burst is distinct from GRB 170121A (trigger 506655418 / 170121067), which was also detected by POLAR (H.L. Xiao et al. 2017, GCN 20501).
A potential optical counterpart to GRB 170121B was detected by MASTER, although it was referenced as GRB 170121A (V. Lipunov et al. 2017, GCN 20502).
The on-ground calculated location, using the GBM trigger data, is RA = 72.84, DEC = -12.65, with an uncertainty of 1.78 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which we have characterized as a core-plus-tail model, with 90% of GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32] ).
The angle from the Fermi LAT boresight at the GBM trigger time is 74 degrees.
The GBM light curve shows two main peaks with a duration (T90) of about 46 s (50-300 keV). The time-averaged spectrum from T0-2.05 s to T0+43.01 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.00 +/- 0.02 and the cutoff energy, parameterized as Epeak, is 455.90 +/- 27.70 keV.
The event fluence (10-1000 keV) in this time interval is (2.97 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+24.6 s in the 10-1000 keV band is 9.4 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN Circular #20508
C. Guidorzi (U. Ferrara), S. Kobayashi, I.A. Steele (LJMU), A. Gomboc (U. Nova Gorica), C.G. Mundell (U. Bath) on behalf of a large collaboration report:
We observed Fermi GRB 170121B (Hamburg et al. GCN 20505) on January 23, 07:21 UT (1.7 days since the GRB) with the 2-m LCO Faulkes Telescope North in Hawaii with SDSS r and i filters. We do not detect the MASTER optical counterpart (Lipunov et al. GCN 20502) down to the following limits:
```
Mid Time      Exposure       Filter       Magnitude (AB)
(days)           (s)
-------------------------------------------------------
1.69            2x120        SDSS-R        > 21.0
1.69            2x120        SDSS-I        > 19.5
-------------------------------------------------------
```
as calibrated against nearby USNO-URAT1 sources.
GCN Circular #20510
B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), A.P. Beardmore (U. Leicester), S.L. Gibson (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), A. Cholden-Brown (PSU), P.A. Evans (U. Leicester) and A.A. Breeveld (UCL-MSSL) report on behalf of the Swift team:
Swift-XRT has performed follow-up observations of the optical transient reported by Lipunov et al. (GCN Circ. 20502) as a possible candidate afterglow of the Fermi/GBM-detected burst GRB 170121B (Hamburg et al. GCN Circ. 20505), collecting 4.5 ks of Photon Counting (PC) mode data between T0+124.0 ks and T0+147.4 ks.
No X-ray sources have been detected at the position of the optical transient reported by Lipunov et al. (GCN Circ. 20502).
An uncatalogued X-ray source is detected within the XRT field of view at the position RA, Dec 72.6361, -9.2424 which is equivalent to:
```
   RA(J2000)  = 04h 50m 32.66s
   Dec(J2000) = -09d 14' 32.5"
```
with an uncertainty of 2.7 arcseconds (radius, 90% containment). The source has a 0.3-10 keV count rate of about 9e-3 ct/sec. We cannot determine fading at this time.
The 3-sigma upper limit in the field ranges from ~2e-3 to ~3e-3 ct s^-1, corresponding to a 0.3-10 keV observed flux of 6.5e-14 to 1.0e-13 erg cm^-2 s^-1 (assuming a typical GRB spectrum).
The results of the XRT-team automatic analysis of the XRT observations, including a position specific upper limit calculator, are available at http://www.swift.ac.uk/ToO_GRBs/00020729.
The Swift/UVOT began settled observations 124 ks after the trigger (Hamburg et al, GCN Circ. 20505). Summing up the early white data at the position of the OT found by Lipunov et al. (GCN Circ. 20502) we do not find any source to an upper limit of 22.2 mags in 3430s. At the position of the new uncatalogued XRT source described above we do see a source already listed in the USNO-B1.0 catalogue and it is not fading.
This circular is an official product of the Swift team.
GCN Circular #20511
V.Sharma, D. Bhattacharya and V. Bhalerao (IUCAA), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the Astrosat CZTI collaboration:
Analysis of AstroSat CZTI data showed clear detection of GRB170121B (Fermi GBM detection: R.Hamburg et al., GCN Circ. 20505) in the 40-200 keV energy range. The light curve shows two peaks structure with brightest peak at 14:44:31.41 UT, 9 seconds after the Fermi trigger. The measured peak count rate is 320.2 counts/sec above the background in combined data of four quadrants, with a total of 4185.9 counts. The local mean background count rate was 344.2 counts/sec. Using cumulative rates, we measure a T90 of 28.3 secs.
CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb . CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.
GCN Circular #20514
V. Lipunov, E. Gorbovskoy, E.Popova, N.Tyurina, V.Kornilov, D.Kuvshinov, N.Tyurina, A.V.Krylov, I.Gorbunov, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D.Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institut of MSU
V.Yurkov, Yu.Sergienko Blagoveschensk Educational State University, Blagoveschensk
K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk, O. Ershova Irkutsk State University
A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
R.Podesta, C.Lopez, F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) , National University of San Juan, Argentina
H. Levato, C. Saffe Instituto de Ciencias Astronomicas,de la Tierra y del Espacio (ICATE), San Juan, Argentina
D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Blagoveschensk was pointed to the Fermi trigger Number 506702667 (Hamburg et al., 20505) 72 sec after notice time and 171 sec after trigger time at 2017-01-21 14:47:14 UT.
MASTER-Amur auto-detection system discovered MASTER OT J045017.73-091602.0 with unfiltered magnitude is 14.9m (limit 16.0 m) (Lipunov et al., GCN 20502).
We do not see any optical source at Swift XRT position (Sbarufatti et al., GCN 20510) with next limits:
```
  Date         UT        Exp        Type        Limit
             start

2017-01-21 14:50:48 	60	Alert (FERMI)	16.6
2017-01-21 14:49:21     60	Alert (FERMI)	16.1
2017-01-21 14:48:11     40	Alert (FERMI)	16.4
2017-01-21 14:47:14     30	Alert (FERMI)	16.0
2017-01-21 14:46:28     20	Alert (FERMI)	16.0
```
The message may be cited.
GCN Circular #20516
E. Mazaeva (IKI), A. Pozanenko (IKI), R. Inasaridze (AbAO), A. Volnova (IKI), V. Ayvazian (AbAO), O.Kvaratskhelia (AbAO), G. Inasaridze (AbAO), I. Molotov (KIAM), report on behalf of larger GRB follow-up collaboration:
We observed the field of optical transient reported by Lipunov et al. (GCN 20502) as a possible candidate of the Fermi/GBM GRB 170121B (Hamburg et al. GCN Circ. 20505) and XRT afterglow candidate reported by Sbarufatti et al. (GCN 20510) with AS-32 (0.7m) telescope of Abastumani Observatory starting on Jan., 23 (UT) 16:14:49. We obtained several unfiltered images of the field. We do not find any source at coordinates of the optical transient (Lipunov et al., GCN 20502). Within XRT error circle (Sbarufatti et al., GCN 20510) we find the source which is also presented in DSS2 and USNO-B1.0 as the star USNO-B1.0 0807-0048671 (magnitudes R1 = 17.94, R2 = 17.07). Preliminary photometry of the source and the field of the optical transient (Lipunov et al., GCN 20502) is following
```
Date        UT start   t-T0      Filter Exp.   OT    Err UpLim (3 sigma)
                       (mid, days)       (s)

2017-01-23 16:14:49.   2.09866   CR     60*60  17.76  0.07  22.9
```
Photometry is based on nearby USNO-B1.0 stars (R2 magnitudes)
```
USNO-B.1_id    R2
0807-0048576 16.37
0806-0049543 18.47
0807-0048525 17.28
0807-0048536 17.23
0806-0049637 15.57
0807-0048826 15.71
0807-0048833 15.41
0807-0048816 17.22
```

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Jochen Greiner, last update: 26-Jan-2017 [Disclaimer]