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) (Jul 30, 2021).
| Type | Comet name | Obs date | Mag | App | T | Pow | Dia | DC | Tail | PA | Obs |
|---|---|---|---|---|---|---|---|---|---|---|---|
| V | C/2017 K2 | 2021 07 29.91 | 12.7 | 29.8 | L | 108 | 1.3 | 3 | HAR11 | ||
| C | C/2017 K2 | 2021 07 29.91 | 13.1 | 10.0 | R | C126 | 3.5 | 0.12 | 9 | FRIaa | |
| C | C/2020 T2 | 2021 07 29.86 | 10.2 | 10.0 | R | B043 | 13 | FRIaa | |||
| C | C/2017 K2 | 2021 07 29.01 | 13.0 | 25.4 | Y | a880 | 1.2 | BAMaa | |||
| C | C/2020 PV6 | 2021 07 27.98 | 14.3 | 8.0 | C | a840 | 0.8 | CARah | |||
| C | C/2021 D2 | 2021 07 27.96 | 18.1 | 31.5 | C | a900 | 0.4 | CARah | |||
| C | C/2019 O3 | 2021 07 27.95 | 17.0 | 31.5 | C | A080 | 0.4 | CARah | |||
| C | C/2017 K2 | 2021 07 27.93 | 13.2 | 31.5 | C | a900 | 1.3 | CARah | |||
| V | C/2017 K2 | 2021 07 27.92 | 12.2 | 20.3 | T | 133 | 1 | 4/ | GON05 | ||
| C | C/2019 K7 | 2021 07 27.91 | 17.2 | 31.5 | C | A080 | 0.4 | CARah | |||
| V | C/2020 T2 | 2021 07 27.91 | 9.9 | 20.3 | T | 77 | 6 | 3/ | GON05 | ||
| V | C/2020 J1 | 2021 07 27.90 | 11.3 | 20.3 | T | 77 | 4 | 1/ | GON05 | ||
| C | C/2020 T2 | 2021 07 27.89 | 10.9 | 31.5 | C | a720 | 4.1 | CARah | |||
| V | C/2017 K2 | 2021 07 27.41 | 13.5 | 25.0 | L | 179 | 0.8 | 3 | WYA | ||
| V | C/2020 T2 | 2021 07 27.40 | 10.4 | 25.0 | L | 40 | 5 | 5 | WYA | ||
| C | C/2017 K2 | 2021 07 26.03 | 13.0 | 10.0 | R | B160 | 3.3 | DEK01 | |||
| C | C/2020 PV6 | 2021 07 23.91 | 14.4 | 10.0 | R | a841 | 1.3 | FRIaa | |||
| C | C/2020 T2 | 2021 07 23.88 | 10.5 | 10.0 | R | B644 | 8.1 | FRIaa | |||
| C | 4P | 2021 07 23.01 | 12.7 | 10.0 | R | A200 | 1.7 | DEK01 | |||
| C | C/2017 K2 | 2021 07 22.96 | 12.9 | 10.0 | R | B400 | 3.3 | DEK01 |
| Comet name | Mag | Trend | Observable | Visiblity 45N |
Visiblity 45S |
|---|---|---|---|---|---|
| C/2020 T2 (Palomar) | 10.5 | fade | 87N to 90S | Evening | Best evening |
| 8P/Tuttle | 10.5 | bright | 90N to 65S | Early evening | Early evening |
| 15P/Finlay | 11.0 | fade | 90N to 66S | Early evening | Early evening |
| C/2021 O1 (Nishimura) | 11.0 | bright | 90N to 59S | Early evening | Early evening |
| 342P/SOHO | 11.5 | bright | 43N to 90S | Never up | Never up |
| 7P/Pons-Winnecke | 11.5 | fade | 43N to 90S | Never up | Never up |
| C/2019 L3 (ATLAS) | 11.5 | bright | 90N to 42S | All night | Never up |
| 4P/Faye | 12.0 | bright | 90N to 72S | Best morning | Early evening |
| C/2020 X3 (SOHO) | 12.5 | fade | 68N to 90S | Evening | Best evening |
| C/2017 K2 (PANSTARRS) | 13.0 | bright | 90N to 51S | 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 | 82N to 90S | Evening | Evening |
| C/2019 T4 (ATLAS) | 14.0 | steady | 68N to 90S | Early evening | Evening |
| 29P/Schwassmann-Wachmann | 14.0 | steady | 90N to 60S | Best morning | Early evening |
| 67P/Churyumov-Gerasimenko | 14.0 | bright | 90N to 85S | Best morning | Best morning |
| 205P-B/Giacobini | 14.0 | bright | 90N to 75S | Best morning | Best morning |
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 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).
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.
