Comet C/2021 A1 (Leonard)
Image of comet C/2021 A1 (Leonard), obtained on 2021 December 28 (around 20h UT) from the ORM Observatory
on La Palma, Canary Islands, with 200 mm, f/3.2 hypergraph and Canon 6D camera. Exposure time was 5 minutes at ISO 3200.
Copyright © 2021 by Jure Skvarč.
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Light-curve of C/2021 A1 (Leonard) (Jan 28, 2022).
| Type | Comet name | Obs date | Mag | App | T | Pow | Dia | DC | Tail | PA | Obs |
|---|---|---|---|---|---|---|---|---|---|---|---|
| V | C/2017 K2 | 2022 01 28.21 | 12.1 | 30.5 | L | 188 | 1 | 2/ | KAR02 | ||
| C | 173P | 2022 01 27.96 | [17.5 | 20.3 | Y | B400 | BUIaa | ||||
| C | 116P | 2022 01 27.94 | 14.4 | 20.3 | Y | A980 | & 0.3 | & 2.5m | 285 | BUIaa | |
| V | 67P | 2022 01 27.90 | 9.5 | 20.0 | L | 42 | & 5 | 3 | SCH04 | ||
| C | 67P | 2022 01 27.90 | 9.8 | 20.3 | Y | C600 | & 4 | >21.0m | 288 | BUIaa | |
| V | C/2019 L3 | 2022 01 27.89 | 9.3 | 20.0 | L | 42 | 3 | 6 | SCH04 | ||
| C | 4P | 2022 01 27.87 | 12.6 | 20.3 | Y | a720 | & 0.8 | BUIaa | |||
| C | 104P | 2022 01 27.84 | 10.5 | 20.3 | Y | a720 | & 4 | BUIaa | |||
| C | 19P | 2022 01 27.83 | 9.7 | 20.3 | Y | A200 | & 4 | BUIaa | |||
| C | C/2019 L3 | 2022 01 27.81 | 9.2 | 28.0 | T | A468 | 6 | JAMaa | |||
| V | C/2019 L3 | 2022 01 27.80 | 9.2 | 25.4 | T | 96 | 3.4 | 5 | COLac | ||
| V | 67P | 2022 01 27.80 | 10.2 | 25.4 | T | 96 | 2.2 | 3/ | COLac | ||
| V | 104P | 2022 01 27.79 | 10.0 | 25.4 | T | 96 | 2.6 | 3 | COLac | ||
| V | 19P | 2022 01 27.78 | 9.1 | 25.4 | T | 96 | 2.9 | 4/ | COLac | ||
| V | 19P | 2022 01 26.78 | 9.6 | 25.0 | C | 96 | 3 | 6 | 5.0m | 25 | DECaa |
| V | C/2019 L3 | 2022 01 26.77 | 8.5 | 25.0 | C | 96 | 1 | 4 | DECaa | ||
| V | 104P | 2022 01 26.76 | 9.7 | 25.0 | C | 62 | 6 | 2 | DECaa | ||
| C | 19P | 2022 01 26.74 | 9.1 | 30.0 | A | a 30 | 3 | PAP04 | |||
| V | C/2019 L3 | 2022 01 26.74 | 9.0 | 5.0 | B | 12 | 3 | 7 | PAP04 | ||
| C | 67P | 2022 01 26.73 | 9.6 | 30.0 | A | a 30 | 1 | PAP04 |
| Comet name | Mag | Trend | Observable | Visiblity 45N |
Visiblity 45S |
|---|---|---|---|---|---|
| 19P/Borrelly | 9.0 | steady | 90N to 88S | Evening | Evening |
| C/2021 A1 (Leonard) | 9.0 | fade | 54N to 90S | Early evening | Evening |
| C/2019 L3 (ATLAS) | 9.0 | steady | 90N to 63S | Best morning | Best evening |
| 104P/Kowal | 10.0 | fade | 90N to 87S | Evening | Evening |
| 67P/Churyumov-Gerasimenko | 10.0 | fade | 90N to 61S | Best morning | Best morning |
| 29P/Schwassmann-Wachmann | 11.5 | steady | 90N to 60S | Best evening | Evening |
| C/2017 K2 (PANSTARRS) | 11.5 | bright | 90N to 78S | Early evening | Early evening |
| 9P/Tempel 1 | 12.0 | bright | 70N to 90S | Early evening | Early evening |
| 4P/Faye | 12.5 | fade | 90N to 80S | Best evening | Best evening |
| 83D/Russell | 12.5 | bright | 66N to 90S | Early evening | Early evening |
| C/2019 T4 (ATLAS) | 12.5 | bright | 60N to 90S | Best morning | Best morning |
| 8P/Tuttle | 13.5 | fade | 35N to 90S | Never up | Never up |
| 116P/Wild | 13.5 | bright | 90N to 72S | Best morning | Best morning |
| P/2013 PA104 (PANSTARRS) | 13.5 | fade | 84N to 90S | Best evening | Best evening |
| 97P/Metcalf-Brewington | 13.5 | fade | 88N to 90S | Evening | Evening |
| 181P/Shoemaker-Levy | 13.5 | fade | 87N to 90S | Evening | Early evening |
| 100P/Hartley | 14.0 | bright | 90N to 55S | Best morning | 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.
A study has solved a 90-year-old mystery by proving the mechanism by which dicarbon -- the chemical that makes some comets' heads green -- is broken up by sunlight. This explains why the vibrant green color never reaches the comet's tail.
Recently we have observed a rapid change in brightness of comet C/2021 A1 (Leonard). Magnitude of this comet should be strongly enhanced by forward scattering around 14. and 15. December 2021 and the days around this date. However observations indicating possible outburst near this date.
CBET 5064 & MPEC 2021-V21, issued on 2021, November 02, announce the discovery of a new comet (magnitude ~19) by A. Maury and G. Attard on CCD images taken on October 24.3 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 P/2021 U3 (Attard-Maury). This is the 4th amateur comet discovery of 2021. It is also the second comet discovered using the synthetic tracking technique (using TYCHO software).
A new article proposes that space probes could hitch a ride with 'centaurs' as they become comets. Along the way, the spacecraft would gather data that would otherwise be impossible to record -- including how comets, Earth-like planets, and even the solar system formed.
CBET 5029 & MPEC 2021-R98 , issued on 2021, September 06, announce the discovery of a new comet (magnitude ~17) on CCD images taken on August 29.6 UT with a 0.5-m f/2 Schmidt reflector at Haleakala, Hawaii, in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program. The new comet has been designated P/2021 Q5 (ATLAS).
