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🌎 Location: Greenwich, United Kingdom [change]

Comet C/2020 H4 (Leonard)

Comet C/2020 H4 (Leonard) is currently in the constellation of Sextans. The current Right Ascension of Comet C/2020 H4 (Leonard) is 10h 49m 58s and the Declination is +02° 21’ 02” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet C/2020 H4 (Leonard) is 18.35 (JPL).

Summary of key facts about Comet C/2020 H4 (Leonard) [tip: you can also create a Quick Access page for this data if you access it frequently and would like to have a simpler view]:

10h 49m 58s
+02° 21’ 02”

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Additional information about Comet C/2020 H4 (Leonard) available on TheSkyLive:

Available Resources

Comet C/2020 H4 (Leonard) Position and Finder Charts

Below we provide Comet C/2020 H4 (Leonard) 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.

Map showing Comet C/2020 H4 (Leonard) in Sextans on October, 28 2020
Field of view: 50x30 degrees
View fullscreen
Map showing Comet C/2020 H4 (Leonard) in Sextans on October, 28 2020
Field of view: 10x6 degrees
View fullscreen
 = visible to the naked eye
 = binocular, brighter than 10th magnitude
= current altitude ≥ 30°   = current altitude < 30°   = below the horizon
Location: Greenwich, United Kingdom [change]

Higher precision deep sky finder chart, 60 arcmin wide, showing where Comet C/2020 H4 (Leonard) is right now. Click on the image to see a more detailed fullscreen tracker view.

C/2020 H4 (Leonard)
RA: 10h 49m 58s
Dec: +02° 21’ 02”
Deep sky finder chart for Comet C/2020 H4 (Leonard)
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet C/2020 H4 (Leonard)?, a page that provides all the information needed to find Comet C/2020 H4 (Leonard) in the sky and additional links to sky charts.

Comet C/2020 H4 (Leonard) Distance from Earth

The distance of Comet C/2020 H4 (Leonard) from Earth is currently 262,130,186 kilometers, equivalent to 1.752232 Astronomical Units. Light takes 14 minutes and 34.3722 seconds to travel from Comet C/2020 H4 (Leonard) and arrive to us.

14 minutes and 34.3722 seconds

The following chart shows the distance of Comet C/2020 H4 (Leonard) 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.

Distance of Comet C/2020 H4 (Leonard) from Earth between January 2013 and December 2100

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/2020 H4 (Leonard) from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet C/2020 H4 (Leonard) to Earth

Between January 2013 and December 2100, the closest approach of Comet C/2020 H4 (Leonard) to Earth happens on Thu Jul 9 2020 at a distance of 1.151026 Astronomical Units, or 172,191,085 kilometers:

Thu Jul 9 2020

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

Comet C/2020 H4 (Leonard) brightness

The current visual magnitude of Comet C/2020 H4 (Leonard) is 18.35.


The observed magnitude and coma diameter values are derived from the Comet Observers Database by averaging the values reported in recent observations (more recent than 4 days), when available. The Estimated Magnitude comes from the JPL Horizons ephemerides service and might be inaccurate given the highly dynamic and unpredictable behavior of comets. When available, please refer to the Observed Magnitude value and consider the Estimated 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.

The following chart is the predicted light curve (visual magnitude as a function of time) of Comet C/2020 H4 (Leonard), 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.

Predicted magnitude of Comet C/2020 H4 (Leonard) between January 2013 and December 2100

Comet C/2020 H4 (Leonard) rise and set times

Location: Greenwich, United Kingdom [change]
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

Today's Comet C/2020 H4 (Leonard) rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 87.7°
Max altitude: 40.7°
Azimuth: 272.0°

The rise and set times are defined as the time at which the upper limb of Comet C/2020 H4 (Leonard) touches the horizon, considering the effect of the atmospheric refraction. As the atmospheric conditions cannot be modeled precisely the times reported here should be considered correct with an approximation of few minutes.

Comet C/2020 H4 (Leonard) Orbital Elements

The following table lists the orbital elements of Comet C/2020 H4 (Leonard) at epoch 29 April 2020 00:00 UTC (JD: 2458969.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.99332064
Orbit inclination i 84.32043228°
Perihelion distance q 0.93829415 AU
140,366,807 km
Aphelion distance Q 280.01482273 AU
41,889,621,329 km
Semi-major axis a 140.47655844 AU
21,014,994,068 km
Orbital period period 1,665.0000 years
608,140.9037 days
Date of perihelion transit Tp 2020-Aug-29 05:57:35
2,459,090.7483 JD
Next perihelion transit 3685-Sep-10 03:38
3,067,231.6520 JD
Argument of perihelion peri 116.77252619229°
Longitude of the ascending node node 307.76792764424°
Mean anomaly M 359.92822486082°
Mean motion n 0.00059197°/day

Visualization of Comet C/2020 H4 (Leonard) Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet C/2020 H4 (Leonard) with respect of the Sun and the orbits of the major planets. The position of Comet C/2020 H4 (Leonard) 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 C/2020 H4 (Leonard)
View Comet C/2020 H4 (Leonard) in the 3D Solar System Simulator

Comet C/2020 H4 (Leonard) 15 Days Ephemeris

The following table lists the ephemerides of Comet C/2020 H4 (Leonard) computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet C/2020 H4 (Leonard) in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2020 Oct 21 10h 50m 38s +06° 47’ 17” 18.26 Leo
2020 Oct 22 10h 50m 35s +06° 09’ 29” 18.27 Sextans
2020 Oct 23 10h 50m 31s +05° 31’ 37” 18.29 Sextans
2020 Oct 24 10h 50m 26s +04° 53’ 47” 18.30 Sextans
2020 Oct 25 10h 50m 21s +04° 15’ 52” 18.31 Sextans
2020 Oct 26 10h 50m 15s +03° 37’ 58” 18.33 Sextans
2020 Oct 27 10h 50m 07s +03° 00’ 00” 18.34 Sextans
2020 Oct 28 10h 49m 59s +02° 22’ 00” 18.35 Sextans
2020 Oct 29 10h 49m 49s +01° 43’ 58” 18.36 Sextans
2020 Oct 30 10h 49m 37s +01° 05’ 52” 18.38 Sextans
2020 Oct 31 10h 49m 26s +00° 27’ 42” 18.39 Sextans
2020 Nov 01 10h 49m 12s -00° 10’ 27” 18.40 Sextans
2020 Nov 02 10h 48m 56s -00° 48’ 43” 18.41 Sextans
2020 Nov 03 10h 48m 41s -01° 27’ 02” 18.42 Sextans