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Comet 261P/Larson

Comet 261P/Larson is currently in the constellation of Cancer. The current Right Ascension of Comet 261P/Larson is 08h 42m 48s and the Declination is +15° 07’ 21” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet 261P/Larson is 28.03 (JPL).

Summary of key facts about Comet 261P/Larson [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]:

08h 42m 48s
+15° 07’ 21”
  • 261P/Larson is above the horizon from Greenwich, United Kingdom [change].
  • It is visible looking in the East direction at an altitude of 23° above the horizon.
  • Given its current magnitude, 261P/Larson is visible only through long exposure photography.
  • See also 261P/Larson rise and set times.
  • 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.

Additional information about Comet 261P/Larson available on TheSkyLive:

Available Resources

Comet 261P/Larson Position and Finder Charts

Below we provide Comet 261P/Larson 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 261P/Larson in Cancer on May, 18 2021
Field of view: 50x30 degrees
View fullscreen
Map showing Comet 261P/Larson in Cancer on May, 18 2021
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 261P/Larson is right now. Click on the image to see a more detailed fullscreen tracker view.

RA: 08h 42m 48s
Dec: +15° 07’ 21”
Deep sky finder chart for Comet 261P/Larson
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet 261P/Larson?, a page that provides all the information needed to find Comet 261P/Larson in the sky and additional links to sky charts.

Comet 261P/Larson Distance from Earth

The distance of Comet 261P/Larson from Earth is currently 682,056,950 kilometers, equivalent to 4.559269 Astronomical Units. Light takes 37 minutes and 55.0971 seconds to travel from Comet 261P/Larson and arrive to us.

37 minutes and 55.0971 seconds

The following chart shows the distance of Comet 261P/Larson 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 261P/Larson 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 261P/Larson from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet 261P/Larson to Earth

Between January 2013 and December 2100, the closest approach of Comet 261P/Larson to Earth happens on Sat Sep 1 2091 at a distance of 1.072415 Astronomical Units, or 160,430,959 kilometers:

Sat Sep 1 2091

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

Comet 261P/Larson brightness

The current visual magnitude of Comet 261P/Larson is 28.03.


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 261P/Larson, 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 261P/Larson between January 2013 and December 2100

Comet 261P/Larson 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 261P/Larson rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 74.9°
Max altitude: 53.6°
Azimuth: 285.1°

The rise and set times are defined as the time at which the upper limb of Comet 261P/Larson 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 261P/Larson Orbital Elements

The following table lists the orbital elements of Comet 261P/Larson at epoch 02 February 2014 00:00 UTC (JD: 2456691.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.39180443
Orbit inclination i 6.33623094°
Perihelion distance q 2.18441329 AU
326,783,578 km
Aphelion distance Q 4.99884623 AU
747,816,754 km
Semi-major axis a 3.59162976 AU
537,300,166 km
Orbital period period 6.8100 years
2,486.1983 days
Date of perihelion transit Tp 2012-Sep-30 01:37:27
2,456,200.5677 JD
Next perihelion transit 2019-Jul-22 06:23
2,458,686.7660 JD
Argument of perihelion peri 58.973808538968°
Longitude of the ascending node node 298.42595846818°
Mean anomaly M 71.086700702213°
Mean motion n 0.14479939°/day

Visualization of Comet 261P/Larson Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet 261P/Larson with respect of the Sun and the orbits of the major planets. The position of Comet 261P/Larson 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 261P/Larson
View Comet 261P/Larson in the 3D Solar System Simulator

Comet 261P/Larson 15 Days Ephemeris

The following table lists the ephemerides of Comet 261P/Larson computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet 261P/Larson in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2021 May 11 08h 38m 26s +15° 23’ 17” 27.91 Cancer
2021 May 12 08h 38m 58s +15° 21’ 19” 27.93 Cancer
2021 May 13 08h 39m 33s +15° 19’ 18” 27.94 Cancer
2021 May 14 08h 40m 06s +15° 17’ 13” 27.96 Cancer
2021 May 15 08h 40m 41s +15° 15’ 07” 27.97 Cancer
2021 May 16 08h 41m 17s +15° 12’ 59” 27.99 Cancer
2021 May 17 08h 41m 53s +15° 10’ 46” 28.01 Cancer
2021 May 18 08h 42m 29s +15° 08’ 31” 28.02 Cancer
2021 May 19 08h 43m 06s +15° 06’ 14” 28.04 Cancer
2021 May 20 08h 43m 44s +15° 03’ 53” 28.05 Cancer
2021 May 21 08h 44m 22s +15° 01’ 31” 28.07 Cancer
2021 May 22 08h 45m 01s +14° 59’ 04” 28.08 Cancer
2021 May 23 08h 45m 39s +14° 56’ 36” 28.09 Cancer
2021 May 24 08h 46m 19s +14° 54’ 06” 28.11 Cancer