C/2020 R4 (ATLAS)
Image of comet C/2020 R4 (ATLAS), obtained on 2021 May 10 (20h24-20h49UT) with 19-cm, f/4 Flat Field Camera and Canon EOS 700D DSLR. Exposure time was 23x60 seconds at ISO 3200. Total exposure time 23 minutes.
Copyright © 2021 by H. Mikuz, Črni Vrh Observatory.
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Light-curve of C/2020 T2 (Palomar) (Jun 18, 2021).
| Type | Comet name | Obs date | Mag | App | T | Pow | Dia | DC | Tail | PA | Obs |
|---|---|---|---|---|---|---|---|---|---|---|---|
| C | C/2017 K2 | 2021 06 17.01 | 13.2 | 10.0 | R | B100 | 2.7 | 0.4m | 220 | DEK01 | |
| C | C/2020 J1 | 2021 06 16.98 | 13.6 | 10.0 | R | A350 | 1.3 | DEK01 | |||
| V | C/2017 K2 | 2021 06 16.97 | 12.7 | 29.8 | L | 132 | 0.7 | 3 | HAR11 | ||
| C | C/2020 T2 | 2021 06 16.96 | 10.7 | 10.0 | R | A800 | 6.7 | 9.7m | 118 | DEK01 | |
| C | C/2021 A1 | 2021 06 16.93 | 16.9 | 10.0 | R | C150 | 0.5 | DEK01 | |||
| V | C/2020 T2 | 2021 06 16.92 | 10.4 | 25.0 | L | 60 | 2 | d3/ | FIL04 | ||
| V | C/2017 K2 | 2021 06 16.09 | 14.5 | 25.0 | L | 120 | TRAab | ||||
| C | C/2017 K2 | 2021 06 16.05 | 12.8 | 10.0 | R | B100 | 2 | DEK01 | |||
| C | C/2020 T2 | 2021 06 15.96 | 10.6 | 10.0 | R | A800 | 6.7 | 8.0m | 127 | DEK01 | |
| C | C/2021 A1 | 2021 06 15.93 | 16.7 | 10.0 | R | C150 | 0.5 | DEK01 | |||
| C | 7P | 2021 06 15.83 | 10.5 | 10.6 | R | a600 | 17.5 | 8.5m | 260 | HER02 | |
| C | 15P | 2021 06 15.81 | 11.6 | 51.0 | Y | a120 | 4.5 | 4 | 2.5m | 243 | CHAab |
| C | 7P | 2021 06 15.81 | 11.2 | 51.0 | Y | a120 | 6 | 6.0m | 264 | CHAab | |
| V | C/2017 K2 | 2021 06 15.50 | 13.5 | 40.0 | L | 108 | 1.3 | 4 | WYA | ||
| V | C/2020 J1 | 2021 06 15.48 | 13.6 | 40.0 | L | 182 | 1.8 | 6 | WYA | ||
| V | C/2019 F1 | 2021 06 15.47 | 14.7 | 40.0 | L | 182 | 0.6 | 6 | WYA | ||
| V | C/2020 T2 | 2021 06 15.46 | 10.6 | 40.0 | L | 59 | 4 | 6 | 8.0m | 118 | WYA |
| C | C/2020 S3 | 2021 06 15.45 | 15.8 | 61.0 | Y | a480 | 1.7 | > 0.25 | 260 | HER02 | |
| C | C/2020 S3 | 2021 06 15.45 | 17.0 | 61.0 | Y | a480 | 0.4 | HER02 | |||
| V | 7P | 2021 06 15.22 | 11.2 | 22.0 | L | 160 | 3 | 3/ | GOI |
| Comet name | Mag | Trend | Observable | Visiblity 45N |
Visiblity 45S |
|---|---|---|---|---|---|
| C/2020 T2 (Palomar) | 10.5 | steady | 90N to 75S | Best morning | Best evening |
| 6P/dArrest | 11.0 | bright | 90N to 73S | Best morning | Best morning |
| 7P/Pons-Winnecke | 11.5 | fade | 66N to 90S | Early evening | Best morning |
| C/2019 L3 (ATLAS) | 12.0 | bright | 90N to 40S | All night | Never up |
| C/2020 X3 (SOHO) | 12.5 | fade | 68N to 90S | Evening | Best evening |
| 15P/Finlay | 12.5 | bright | 90N to 83S | Early evening | Early evening |
| C/2020 J1 (SONEAR) | 13.0 | fade | 73N to 90S | Best evening | Best evening |
| C/2017 K2 (PANSTARRS) | 13.0 | bright | 90N to 47S | Best morning | Best morning |
| 8P/Tuttle | 13.0 | bright | 90N to 48S | Early evening | Early evening |
| P/2013 PA104 (PANSTARRS) | 13.5 | fade | 84N to 90S | Best evening | Best evening |
| 246P/NEAT | 13.5 | steady | 59N to 90S | Best morning | Best morning |
| 4P/Faye | 13.5 | bright | 90N to 78S | Early evening | Early evening |
| 29P/Schwassmann-Wachmann | 14.0 | steady | 90N to 61S | Early evening | Early evening |
| C/2019 T4 (ATLAS) | 14.0 | steady | 66N to 90S | Early evening | Evening |
| 342P/SOHO | 14.0 | bright | 56N to 90S | Early evening | Best morning |
| C/2020 K5 (PANSTARRS) | 14.0 | fade | 53N to 90S | Early evening | Evening |
The observable region is an approximate indication of the latitude at which the comet may be seen. The period when visible is calculated for latitude 45°N and 45°S.
CBET 4975 & MPEC 2021-L89, issued on 2021, June 09, announce the discovery of a new comet (magnitude ~19.0) on CCD images taken on May 23.0 UT with the "Mobile Astronomical System of the Telescope-Robots" (MASTER) auto-detection system (double 0.40-m f/2.5 reflector) at the South African Astronomical Observatory. The object was reported by MASTER as a new NEO candidate and has been found to show cometary activity by CCD astrometrists elsewhere. The new comet has been designated C/2021 K2 (MASTER).
CBET 4972 & MPEC 2021-L11, issued on 2021, June 02, announce the discovery of a new comet (magnitude ~19.0) on CCD images taken by A. Maury and G. Attard on May 09.3 UT with the 0.28-m f/2.2 Rowe-Ackermann Schmidt astrograph at San Pedro de Atacama, Chile in the course of the MAP (W94) survey. The new comet has been designated C/2021 J1 (Maury-Attard). This is the first amateur comet discovery of 2021. It is also the first comet ever discovered using the synthetic tracking technique (using TYCHO software).
CBET 4968 & MPEC 2021-K89, issued on 2021, May 27, announce the discovery of a new comet (magnitude ~17.0) on CCD images taken on May 14.5 UT with the 0.5-m reflector + CCD in the course of the ATLAS-HKO (T05) survey. The object was originally found by Peter Veres of Minor Planet Center (MPC) as unusually bright among the MPC's isolated tracklet file (ITF) and linked to the detections from May 22 (F51) and May 14 (T08). A review of the ATLAS images revealed the cometary nature of this object.
New reference catalog keys were assigned for GAIA DR catalog and APASS catalog.
CBET xxxx & MPEC 2021-J71 , issued on 2021, May 06, announce the discovery of an apparently asteroidal object (magnitude ~19.5) on CCD images taken on March 09.5 UT with the 1.2-m Schmidt telescope at Palomar in the course of the "Zwicky Transient Facility" (ZTF) search program. This object has been found to show cometary appearance by CCD astrometrists elsewhere. The new comet has been designated C/2021 E3 (ZTF).
