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) (May 25, 2021).
| Type | Comet name | Obs date | Mag | App | T | Pow | Dia | DC | Tail | PA | Obs |
|---|---|---|---|---|---|---|---|---|---|---|---|
| C | 7P | 2021 05 25.15 | 14.6 | 61.0 | C | a300 | STIaa | ||||
| C | 67P | 2021 05 24.14 | 16.9 | 31.5 | C | a420 | 0.4 | CARah | |||
| C | C/2019 T3 | 2021 05 24.11 | 17.2 | 31.5 | C | a600 | 0.4 | CARah | |||
| C | 7P | 2021 05 24.06 | 11.4 | 10.0 | R | A443 | 6 | FRIaa | |||
| C | C/2019 T3 | 2021 05 24.03 | 17.5 | 10.0 | R | A563 | 0.6 | FRIaa | |||
| C | C/2017 K2 | 2021 05 24.00 | 13.7 | 10.0 | R | A924 | 2.6 | 1.0m | 316 | FRIaa | |
| C | C/2020 M5 | 2021 05 23.97 | 16.0 | 10.0 | R | A924 | 1 | FRIaa | |||
| C | C/2020 T2 | 2021 05 23.93 | 10.3 | 10.0 | R | A924 | 9.7 | FRIaa | |||
| C | C/2020 R4 | 2021 05 23.89 | 12.1 | 10.0 | R | B887 | 8 | 0.11 | 111 | FRIaa | |
| C | 7P | 2021 05 20.07 | 13.9 | 20.3 | Y | B340 | BUIaa | ||||
| C | C/2021 A1 | 2021 05 19.91 | 17.5 | 20.3 | B | D800 | BUIaa | ||||
| C | C/2020 H6 | 2021 05 19.90 | 15.7 | 20.3 | Y | B160 | BUIaa | ||||
| C | C/2020 T2 | 2021 05 19.87 | 10.5 | 20.3 | Y | A200 | & 3 | BUIaa | |||
| V | C/2020 F5 | 2021 05 19.64 | 15.1 | 40.0 | L | 182 | 0.6 | 3/ | WYA | ||
| V | C/2017 K2 | 2021 05 19.63 | 13.8 | 40.0 | L | 182 | 0.8 | 5 | WYA | ||
| V | 7P | 2021 05 19.62 | 12.8 | 40.0 | L | 108 | 2 | 4/ | WYA | ||
| V | C/2020 T2 | 2021 05 19.62 | 11.1 | 40.0 | L | 59 | 3.5 | 6 | WYA | ||
| V | C/2019 F1 | 2021 05 19.61 | 14.9 | 40.0 | L | 261 | 0.5 | 6 | WYA | ||
| V | 246P | 2021 05 19.60 | 14.3 | 40.0 | L | 182 | 0.8 | 4/ | WYA | ||
| V | C/2018 U1 | 2021 05 19.59 | 15.1 | 40.0 | L | 182 | 0.4 | 5/ | WYA |
| Comet name | Mag | Trend | Observable | Visiblity 45N |
Visiblity 45S |
|---|---|---|---|---|---|
| C/2020 T2 (Palomar) | 10.5 | bright | 90N to 65S | Best morning | Best evening |
| 6P/dArrest | 11.5 | bright | 90N to 73S | Best morning | 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 |
| C/2020 R4 (ATLAS) | 12.5 | fade | 90N to 67S | Best evening | Evening |
| 7P/Pons-Winnecke | 12.5 | bright | 82N to 90S | Best morning | Best morning |
| 15P/Finlay | 13.0 | bright | 83N to 90S | Early evening | Early evening |
| C/2020 J1 (SONEAR) | 13.5 | steady | 64N to 90S | Best evening | Best morning |
| P/2013 PA104 (PANSTARRS) | 13.5 | fade | 84N to 90S | Best evening | Best evening |
| 246P/NEAT | 13.5 | bright | 62N to 90S | Best morning | Best morning |
| C/2017 K2 (PANSTARRS) | 13.5 | bright | 90N to 47S | Best morning | Early evening |
| C/2019 T4 (ATLAS) | 14.0 | steady | 64N to 90S | Early evening | Best evening |
| 29P/Schwassmann-Wachmann | 14.0 | steady | 90N to 62S | Poor elongation | Poor elongation |
| C/2020 K5 (PANSTARRS) | 14.0 | steady | 46N to 90S | Early evening | Best morning |
| 4P/Faye | 14.0 | bright | 90N to 83S | Early evening | Early 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.
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).
The world's first ground-based observations of the bare nucleus of a comet nearing the end of its active life revealed that the nucleus has a diameter of 800 meters and is covered with large grains of phyllosilicate; on Earth large grains of phyllosilicate are commonly available as talcum powder. This discovery provides clues to piece together the history of how this comet evolved into its current burnt-out state.
CBET 4953 & MPEC 2021-G80, issued on 2021, April 07, announce that an apparently asteroidal object (magnitude ~21.0) discovered on CCD images obtained with the F51 Pan-STARRS 1 survey's 1.8m Ritchey-Chretien on 2019, October 22.22 and designated A/2019 U5 (cf. MPEC 2019-V10) has been found to show cometary appearance by other CCD observers over the past half year. The new comet has been designated C/2019 U5 (PANSTARRS).
New observations indicate that the rogue comet 2I/Borisov, which is only the second and most recently detected interstellar visitor to our Solar System, is one of the most pristine ever observed. Astronomers suspect that the comet most likely never passed close to a star, making it an undisturbed relic of the cloud of gas and dust it formed from.
CBET 4949 & MPEC 2021-F110, issued on 2021, March 25, announce that an apparently asteroidal object (magnitude ~21.0) discovered on CCD images obtained with the Mt. Lemmon Survey's 1.5-m reflector on 2020 Mar. 22 and designated A/2020 F7 (cf. MPEC 2020-G78) has been found to show cometary appearance by numerous other CCD observers over the past half year. The new comet has been designated C/2020 F7 (Lemmon).
