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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 4:52  
clear_day Transit: 12:55  
SunsetSet: 20:59 south
wb_twilight Astronomical TwilightWhat's Visible Now
Comets » 

Comet Leonard (C/2021 A1)

Comet Leonard (C/2021 A1) is currently in the constellation of Ophiucus.

The current Right Ascension of Comet Leonard (C/2021 A1) is 16h 38m 47s and the Declination is -14° 04’ 35” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom edit_location_alt). The current estimated magnitude of Comet Leonard (C/2021 A1) is 19.84 (JPL).

16h 38m 47s
-14° 04’ 35”

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.

Today's rise, transit and set times of Comet Leonard (C/2021 A1) from Greenwich, United Kingdom edit_location_alt (all times relative to the local timezone Europe/London):

Azimuth: 104.1°
Max altitude: 24.4°
Azimuth: 255.9°
  • C/2021 A1 (Leonard) is above the horizon from Greenwich, United Kingdom edit_location_alt.
  • Right now it is placed in the South-South-East direction at an altitude of 20° above the horizon.
  • 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.

Available Resources

Comet Leonard (C/2021 A1) Position and Finder Charts

Below we provide Comet Leonard (C/2021 A1) finder charts showing where the object is right now in the sky with respect to the brightest stars. The first finder chart has a field of view of 50 degrees, while the second one has a field of view of 10 degrees. Click on each finder chart to access a full screen interactive Online Planetarium.

Finder chart of C/2021 A1 (Leonard) in Ophiucus on May,28 2023
Map showing Comet Leonard (C/2021 A1) in Ophiucus on May, 28 2023
Field of view: 50x30 degrees
View fullscreen
Finder chart of C/2021 A1 (Leonard)
Map showing Comet Leonard (C/2021 A1) in Ophiucus on May, 28 2023
Field of view: 10x6 degrees
View fullscreen

Higher 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.

C/2021 A1 (Leonard)
RA: 16h 38m 47s
Dec: -14° 04’ 35”
Deep sky finder chart for Comet Leonard (C/2021 A1)
Field of view: 60x40 arcmins
View fullscreen

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.

Comet Leonard (C/2021 A1) Distance from Earth

The distance of Comet Leonard (C/2021 A1) from Earth is currently 817,215,911 kilometers, equivalent to 5.462751 Astronomical Units. Light takes 45 minutes and 25.9389 seconds to travel from Comet Leonard (C/2021 A1) and arrive to us.

45 minutes and 25.9389 seconds

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.

Chart of the distance of Comet Leonard (C/2021 A1) from Earth in Astronomical Units (au)

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 of Comet Leonard (C/2021 A1) to Earth

Between 1 January 2013 and 30 December 2100, 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 35,005,002 kilometers:

Mon Dec 13 2021

NOTE: values for the closest approach are computed with a sampling interval of 1 day.

Comet Leonard (C/2021 A1) Brightness and 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.

Chart of the magnitude of Comet Leonard (C/2021 A1) as a function of time

Comet Leonard (C/2021 A1) 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 1.00010051
Orbit inclination i 132.68581276°
Perihelion distance q 0.61523023 AU
92,037,132 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 225.0877083271°
Longitude of the ascending node node 255.8891008128°
Mean anomaly M -0.00036284404038465°
Mean motion n 0.00000206°/day

Visualization of Comet Leonard (C/2021 A1) Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet Leonard (C/2021 A1) with respect of the Sun and the orbits of the major planets. The position of Comet Leonard (C/2021 A1) and the planets along their orbits in this diagram accurately represents the current configuration of the objects in the Solar System. This is an experimental feature and it requires a WebGL enabled browser. Please provide us feedback!

Orbit Diagram of Comet Leonard (C/2021 A1)
View Comet Leonard (C/2021 A1) in the 3D Solar System Simulator

Comet Leonard (C/2021 A1) 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. Click on each row of the table to locate Comet Leonard (C/2021 A1) in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2023 May 21 16h 45m 11s -14° 28’ 50” 19.79 Ophiucus
2023 May 22 16h 44m 21s -14° 25’ 42” 19.80 Ophiucus
2023 May 23 16h 43m 33s -14° 22’ 36” 19.80 Ophiucus
2023 May 24 16h 42m 44s -14° 19’ 31” 19.81 Ophiucus
2023 May 25 16h 41m 57s -14° 16’ 27” 19.81 Ophiucus
2023 May 26 16h 41m 08s -14° 13’ 23” 19.82 Ophiucus
2023 May 27 16h 40m 19s -14° 10’ 20” 19.82 Ophiucus
2023 May 28 16h 39m 32s -14° 07’ 21” 19.83 Ophiucus
2023 May 29 16h 38m 44s -14° 04’ 20” 19.84 Ophiucus
2023 May 30 16h 37m 55s -14° 01’ 23” 19.84 Ophiucus
2023 May 31 16h 37m 08s -13° 58’ 26” 19.85 Ophiucus
2023 Jun 01 16h 36m 20s -13° 55’ 30” 19.85 Ophiucus
2023 Jun 02 16h 35m 31s -13° 52’ 36” 19.86 Ophiucus
2023 Jun 03 16h 34m 45s -13° 49’ 44” 19.87 Ophiucus