Comet Leonard (C/2021 A1)
Comet Leonard (C/2021 A1) is in the constellation of
Ophiuchus,
at a distance of
Finder Charts
View interactive star map
High precision deep sky finder chart, 60 arcmin wide, showing where Comet Leonard (C/2021 A1) is right now. Click on the image to see a more detailed fullscreen tracker view.
Also check out Where is Comet Leonard (C/2021 A1)?, a page that provides all the information needed to find Comet Leonard (C/2021 A1) in the sky and additional links to sky charts.
Celestial Coordinates
Apparent
J2000
Additional Information
The observed values of Magnitude, Coma Diameter and Tail Length are derived from the most recent observation recorded at the Comet Observers Database. The value of Predicted Magnitude comes from the JPL Horizons ephemerides service and, in the case of comets, might be inaccurate given the highly dynamic and unpredictable behavior of these objects. When available, please refer to the Observed Magnitude value and consider the Predicted Magnitude as a directional indication. We acknowledge with thanks the comet observations from the COBS Comet Observation Database contributed by observers worldwide and used in this table to report recent comet observations.
Rise and Set Times
Today's rise, transit and set times of Comet Leonard (C/2021 A1) from Greenwich, UK (all times relative to the local timezone Europe/London):
- C/2021 A1 (Leonard) is below the horizon from Greenwich, UK.
- Given its current magnitude, C/2021 A1 (Leonard) is visible only through long exposure photography.
- Go to interactive sky chart
If you need to access this information frequently for your observations, you can create a simple customized Quick Access page, so that you can easily bookmark it in your browser favorites or add a shortcut to your mobile phones' home screen.
Distance from Earth
The distance of Comet Leonard (C/2021 A1) from Earth is currently
The following chart shows the distance of Comet Leonard (C/2021 A1) from Earth as a function of time. In the chart the distance data is measured in Astronomical Units and sampled with an interval of 1 day.
The value of the reported distance might be somewhat inaccurate around the times of closest approach for objects passing extremely close to Earth. The value of the distance of C/2021 A1 (Leonard) from Earth is also available as a real time updated value in the Live Position and Data Tracker.
Closest Approach
Between 1 January 2000 and 31 December 2099, the closest approach of Comet Leonard (C/2021 A1) to Earth happens on Mon Dec 13 2021 at a distance of 0.233994 Astronomical Units, or 35,005,003 kilometers:
NOTE: values for the closest approach are computed with a sampling interval of 1 day.
Light Curve
The following chart is the predicted light curve (visual magnitude as a function of time) of Comet Leonard (C/2021 A1), according to the most recent ephemerides data. Magnitude data is sampled with a 2 days interval and there might be inaccuracies for objects changing brightness very rapidly during the course of a few days. For comets there could be large discrepancies between the observed and predicted brightness because of their highly dynamic behaviour.
Orbital Elements
The following table lists the orbital elements of Comet Leonard (C/2021 A1) at epoch 10 July 2021 00:00 UTC (JD: 2459406.5). Source: JPL Small-Body Database
| Element | Symbol | Value |
|---|---|---|
| Orbit eccentricity | e | 1.00010048 |
| Orbit inclination | i | 132.68581262° |
| Perihelion distance | q | 0.61523019 AU 92,037,127 km |
| Aphelion distance | Q | n.a. |
| Semi-major axis | a | n.a. |
| Orbital period | period | n.a. |
| Date of perihelion transit | Tp | 2022-Jan-03 07:01:27 2,459,582.7927 JD |
| Argument of perihelion | peri | 225.08771303871° |
| Longitude of the ascending node | node | 255.88910373877° |
| Mean anomaly | M | -0.00036266407886569° |
| Mean motion | n | 0.00000206°/day |
Orbit Visualization
View Comet Leonard (C/2021 A1) in the 3D Solar System Simulator
15 Days Ephemeris
The following table lists the ephemerides of Comet Leonard (C/2021 A1) computed for the past and next 7 days, with a 24 hours interval. Apparent celestial coordinates are provided.
| Date | Right AscensionR.A. | DeclinationDec. | MagnitudeMag | Constellation |
|---|---|---|---|---|
| 2025 Apr 05 | 16h 31m 22s | -07° 19’ 51” | 22.55 | Ophiuchus |
| 2025 Apr 06 | 16h 31m 08s | -07° 17’ 54” | 22.55 | Ophiuchus |
| 2025 Apr 07 | 16h 30m 54s | -07° 15’ 57” | 22.55 | Ophiuchus |
| 2025 Apr 08 | 16h 30m 39s | -07° 14’ 00” | 22.55 | Ophiuchus |
| 2025 Apr 09 | 16h 30m 24s | -07° 12’ 04” | 22.55 | Ophiuchus |
| 2025 Apr 10 | 16h 30m 09s | -07° 10’ 08” | 22.55 | Ophiuchus |
| 2025 Apr 11 | 16h 29m 54s | -07° 08’ 12” | 22.55 | Ophiuchus |
| 2025 Apr 12 | 16h 29m 38s | -07° 06’ 15” | 22.55 | Ophiuchus |
| 2025 Apr 13 | 16h 29m 22s | -07° 04’ 20” | 22.55 | Ophiuchus |
| 2025 Apr 14 | 16h 29m 06s | -07° 02’ 24” | 22.55 | Ophiuchus |
| 2025 Apr 15 | 16h 28m 49s | -07° 00’ 29” | 22.55 | Ophiuchus |
| 2025 Apr 16 | 16h 28m 32s | -06° 58’ 34” | 22.55 | Ophiuchus |
| 2025 Apr 17 | 16h 28m 15s | -06° 56’ 40” | 22.55 | Ophiuchus |
| 2025 Apr 18 | 16h 27m 58s | -06° 54’ 46” | 22.55 | Ophiuchus |
Additional Resources
- Position and finder charts (see also Where is Comet Leonard (C/2021 A1)?)
- Distance from Earth (see also How far is Comet Leonard (C/2021 A1) from Earth?)
- When does Comet Leonard (C/2021 A1) rise and set?
- Brightness (see also How bright is Comet Leonard (C/2021 A1)?)
- Orbital elements. Detailed information about Comet Leonard (C/2021 A1) orbital parameters.
- Interactive orbit visualization. 3d visualization showing the orbit of Comet Leonard (C/2021 A1) with respect to the major Solar System objects.
- 15 days ephemerides. Table showing celestial coordinates and magnitude of Comet Leonard (C/2021 A1) for the past and next 7 days.
- Interactive sky chart. An online planetarium application that shows where to locate Comet Leonard (C/2021 A1) in the sky from your location.
- Live position tracker. A high precision sky chart that uses real deep sky imagery to help locate Comet Leonard (C/2021 A1) with your telescope or on your astrophotographies.