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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 4:49  
clear_day Transit: 12:56  
SunsetSet: 21:04 south
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Comets » 

Comet C/2023 H2 (Lemmon)

Comet C/2023 H2 (Lemmon) is currently in the constellation of Canes Venatici.

The current Right Ascension of Comet C/2023 H2 (Lemmon) is 12h 35m 37s and the Declination is +46° 34’ 09” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom edit_location_alt). The current estimated magnitude of Comet C/2023 H2 (Lemmon) is 19.52 (JPL).

12h 35m 37s
+46° 34’ 09”
Canes Venatici

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 C/2023 H2 (Lemmon) from Greenwich, United Kingdom edit_location_alt (all times relative to the local timezone Europe/London):

Today Comet C/2023 H2 (Lemmon) is circumpolar and transits at 19:55 UTC reaching a maximum altitude of 85.1°.
  • C/2023 H2 (Lemmon) is above the horizon from Greenwich, United Kingdom edit_location_alt.
  • Right now it is placed in the East-North-East direction at an altitude of 51° above the horizon.
  • Given its current magnitude, C/2023 H2 (Lemmon) 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 C/2023 H2 (Lemmon) Position and Finder Charts

Below we provide Comet C/2023 H2 (Lemmon) 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/2023 H2 (Lemmon) in Canes Venatici on June,01 2023
Map showing Comet C/2023 H2 (Lemmon) in Canes Venatici on June, 01 2023
Field of view: 50x30 degrees
View fullscreen
Finder chart of C/2023 H2 (Lemmon)
Map showing Comet C/2023 H2 (Lemmon) in Canes Venatici on June, 01 2023
Field of view: 10x6 degrees
View fullscreen

Higher precision deep sky finder chart, 60 arcmin wide, showing where Comet C/2023 H2 (Lemmon) is right now. Click on the image to see a more detailed fullscreen tracker view.

C/2023 H2 (Lemmon)
RA: 12h 35m 37s
Dec: +46° 34’ 09”
Deep sky finder chart for Comet C/2023 H2 (Lemmon)
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet C/2023 H2 (Lemmon)?, a page that provides all the information needed to find Comet C/2023 H2 (Lemmon) in the sky and additional links to sky charts.

Comet C/2023 H2 (Lemmon) Distance from Earth

The distance of Comet C/2023 H2 (Lemmon) from Earth is currently 335,507,882 kilometers, equivalent to 2.242732 Astronomical Units. Light takes 18 minutes and 39.1338 seconds to travel from Comet C/2023 H2 (Lemmon) and arrive to us.

18 minutes and 39.1338 seconds

The following chart shows the distance of Comet C/2023 H2 (Lemmon) 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 C/2023 H2 (Lemmon) 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/2023 H2 (Lemmon) from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest Approach of Comet C/2023 H2 (Lemmon) to Earth

Between 1 January 2000 and 31 December 2099, the closest approach of Comet C/2023 H2 (Lemmon) to Earth happens on Sat Nov 11 2023 at a distance of 0.193016 Astronomical Units, or 28,874,757 kilometers:

Sat Nov 11 2023

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

Comet C/2023 H2 (Lemmon) Brightness and Light Curve

The following chart is the predicted light curve (visual magnitude as a function of time) of Comet C/2023 H2 (Lemmon), 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 C/2023 H2 (Lemmon) as a function of time

Comet C/2023 H2 (Lemmon) Orbital Elements

The following table lists the orbital elements of Comet C/2023 H2 (Lemmon) at epoch 01 May 2023 00:00 UTC (JD: 2460066.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.99637280
Orbit inclination i 113.75162616°
Perihelion distance q 0.89438096 AU
133,797,487 km
Aphelion distance Q 492.25855692 AU
73,640,832,097 km
Semi-major axis a 246.57646894 AU
36,887,314,792 km
Orbital period period 3,872.0026 years
1,414,248.9678 days
Date of perihelion transit Tp 2023-Oct-29 04:23:20
2,460,246.6829 JD
Argument of perihelion peri 150.64704509475°
Longitude of the ascending node node 217.04191916104°
Mean anomaly M 359.95413407645°
Mean motion n 0.00025455°/day

Visualization of Comet C/2023 H2 (Lemmon) Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet C/2023 H2 (Lemmon) with respect of the Sun and the orbits of the major planets. The position of Comet C/2023 H2 (Lemmon) 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/2023 H2 (Lemmon)
View Comet C/2023 H2 (Lemmon) in the 3D Solar System Simulator

Comet C/2023 H2 (Lemmon) 15 Days Ephemeris

The following table lists the ephemerides of Comet C/2023 H2 (Lemmon) computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet C/2023 H2 (Lemmon) in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2023 May 25 12h 52m 45s +45° 58’ 15” 19.81 Canes Venatici
2023 May 26 12h 50m 25s +46° 04’ 28” 19.77 Canes Venatici
2023 May 27 12h 48m 06s +46° 10’ 13” 19.74 Canes Venatici
2023 May 28 12h 45m 50s +46° 15’ 29” 19.70 Canes Venatici
2023 May 29 12h 43m 35s +46° 20’ 17” 19.66 Canes Venatici
2023 May 30 12h 41m 21s +46° 24’ 38” 19.62 Canes Venatici
2023 May 31 12h 39m 11s +46° 28’ 33” 19.59 Canes Venatici
2023 Jun 01 12h 37m 01s +46° 32’ 04” 19.55 Canes Venatici
2023 Jun 02 12h 34m 54s +46° 35’ 11” 19.51 Canes Venatici
2023 Jun 03 12h 32m 49s +46° 37’ 54” 19.47 Canes Venatici
2023 Jun 04 12h 30m 47s +46° 40’ 14” 19.43 Canes Venatici
2023 Jun 05 12h 28m 46s +46° 42’ 11” 19.40 Canes Venatici
2023 Jun 06 12h 26m 48s +46° 43’ 47” 19.36 Canes Venatici
2023 Jun 07 12h 24m 53s +46° 45’ 03” 19.32 Canes Venatici