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) (Aug 05, 2021).
| Type | Comet name | Obs date | Mag | App | T | Pow | Dia | DC | Tail | PA | Obs |
|---|---|---|---|---|---|---|---|---|---|---|---|
| V | C/2017 K2 | 2021 08 02.94 | 12.0: | 25.0 | L | 167 | & 1 | 3 | FIL04 | ||
| V | C/2015 K2 | 2021 08 02.00 | 12.7 | 29.8 | L | 132 | 0.9 | 2 | HAR11 | ||
| C | 7P | 2021 07 31.97 | 10.5 | 20.0 | L | a720 | 19 | 0.14 | 267 | LEHaa | |
| C | C/2020 F5 | 2021 07 31.95 | 14.4 | 20.0 | L | a900 | 1.6 | 0.16 | 207 | LEHaa | |
| C | C/2017 K2 | 2021 07 31.94 | 13.2 | 10.0 | R | A202 | 2.5 | 0.06 | 19 | FRIaa | |
| C | C/2018 U1 | 2021 07 31.77 | 15.3 | 20.0 | L | a900 | 1.3 | 0.07 | 41 | LEHaa | |
| V | 7P | 2021 07 31.51 | 11.8 | 40.0 | L | 59 | 6 | 3/ | WYA | ||
| V | C/2019 F1 | 2021 07 31.51 | 14.7 | 40.0 | L | 261 | 0.5 | 5/ | WYA | ||
| V | C/2018 U1 | 2021 07 31.50 | 15.0 | 40.0 | L | 261 | 0.5 | 3/ | WYA | ||
| V | C/2020 F5 | 2021 07 31.50 | 14.7 | 40.0 | L | 182 | 0.5 | 6 | WYA | ||
| V | C/2020 T2 | 2021 07 31.48 | 10.4 | 40.0 | L | 59 | 4 | 6 | WYA | ||
| V | C/2017 K2 | 2021 07 31.48 | 13.2 | 40.0 | L | 108 | 1 | 3/ | WYA | ||
| C | C/2019 L3 | 2021 07 30.97 | 11.7 | 27.9 | L | A320 | 2.9 | 0.07 | 310 | LEHaa | |
| C | C/2019 U5 | 2021 07 30.92 | 16.4 | 27.9 | L | A440 | 0.7 | 0.4m | 86 | LEHaa | |
| C | C/2021 A1 | 2021 07 30.89 | 16.2 | 27.9 | L | B520 | 0.7 | 1.2m | 67 | LEHaa | |
| V | C/2020 T2 | 2021 07 30.88 | 9.7 | 12.0 | R | 50 | 4 | 1 | PIL01 | ||
| C | C/2020 T2 | 2021 07 30.76 | 10.0 | 20.0 | L | a720 | 16 | 0.15 | 100 | LEHaa | |
| C | 117P | 2021 07 30.74 | 15.8 | 20.0 | L | A080 | 1.5 | 0.04 | 305 | LEHaa | |
| V | C/2020 F5 | 2021 07 30.50 | 14.9 | 40.0 | L | 182 | 0.6 | 5/ | WYA | ||
| V | 7P | 2021 07 30.50 | 13.0 | 40.0 | L | 108 | 1.9 | 6 | WYA |
| Comet name | Mag | Trend | Observable | Visiblity 45N |
Visiblity 45S |
|---|---|---|---|---|---|
| 8P/Tuttle | 10.0 | bright | 90N to 69S | Early evening | Early evening |
| C/2020 T2 (Palomar) | 10.5 | fade | 84N to 90S | Evening | Best evening |
| C/2021 O1 (Nishimura) | 11.0 | bright | 90N to 59S | Poor elongation | Poor elongation |
| 342P/SOHO | 11.0 | bright | 43N to 90S | Never up | Never up |
| C/2019 L3 (ATLAS) | 11.0 | bright | 90N to 43S | All night | Never up |
| 15P/Finlay | 11.5 | fade | 90N to 65S | Early evening | Early evening |
| 4P/Faye | 12.0 | bright | 90N to 72S | Best morning | Early evening |
| 7P/Pons-Winnecke | 12.0 | fade | 42N to 90S | Never up | Never up |
| C/2020 X3 (SOHO) | 12.5 | fade | 68N to 90S | Evening | Best evening |
| C/2017 K2 (PANSTARRS) | 13.0 | steady | 90N to 52S | Best morning | Evening |
| 67P/Churyumov-Gerasimenko | 13.5 | bright | 90N to 83S | Best morning | Best morning |
| P/2013 PA104 (PANSTARRS) | 13.5 | fade | 84N to 90S | Best evening | Best evening |
| C/2020 J1 (SONEAR) | 14.0 | fade | 83N to 90S | Evening | Evening |
| 205P-B/Giacobini | 14.0 | bright | 90N to 76S | Best morning | Best morning |
| 29P/Schwassmann-Wachmann | 14.0 | steady | 90N to 60S | Best morning | Early evening |
| C/2019 T4 (ATLAS) | 14.0 | steady | 68N 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 xxxx & MPEC 2021-P05, issued on 2021, August 01, announce the discovery of a new comet (magnitude ~20) on CCD images taken on July 26.5 UT with the Pan-STARRS1 1.8-m Ritchey-Chretien reflector at Haleakala. The new comet has been designated C/2021 O3 (PANSTARRS).
CBET 5003 & MPEC 2021-O39, issued on 2021, July 22, announce the discovery of a new comet (magnitude ~20.5) on CCD images taken on July 13.5 UT with the Pan-STARRS1 1.8-m Ritchey-Chretien reflector at Haleakala (numerous pre-discovery observations going back an additional month were later identified). The new comet has been designated C/2021 N3 (PANSTARRS).
CBET 5000 & MPEC 2021-N137, issued on 2021, July 15, announce the discovery of a new comet (magnitude ~18.3) on CCD images taken on July 09.4 UT with the Catalina Sky Survey's 0.68-m Schmidt reflector (pre-discovery Catalina observations from June 27 were identified later). The new comet has been designated P/2021 N2 (Fuls).
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).
