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🌎  Greenwich, United Kingdom [change]

Comet 77P/Longmore

Comet 77P/Longmore is currently in the constellation of Lynx. The current Right Ascension of Comet 77P/Longmore is 07h 51m 15s and the Declination is +40° 59’ 40” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet 77P/Longmore is 19.01 (JPL).

Summary of key facts about Comet 77P/Longmore [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]:

07h 51m 15s
+40° 59’ 40”
  • 77P/Longmore is above the horizon from Greenwich, United Kingdom [change].
  • It is visible looking in the South-South-East direction at an altitude of 78° above the horizon.
  • Given its current magnitude, 77P/Longmore is visible only through long exposure photography.
  • See also 77P/Longmore 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 77P/Longmore available on TheSkyLive:

Available Resources

Comet 77P/Longmore Position and Finder Charts

Below we provide Comet 77P/Longmore 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 77P/Longmore in Lynx on May, 16 2022
Field of view: 50x30 degrees
View fullscreen
Map showing Comet 77P/Longmore in Lynx on May, 16 2022
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 77P/Longmore is right now. Click on the image to see a more detailed fullscreen tracker view.

RA: 07h 51m 15s
Dec: +40° 59’ 40”
Deep sky finder chart for Comet 77P/Longmore
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet 77P/Longmore?, a page that provides all the information needed to find Comet 77P/Longmore in the sky and additional links to sky charts.

Comet 77P/Longmore Distance from Earth

The distance of Comet 77P/Longmore from Earth is currently 518,750,945 kilometers, equivalent to 3.467636 Astronomical Units. Light takes 28 minutes and 50.3669 seconds to travel from Comet 77P/Longmore and arrive to us.

28 minutes and 50.3669 seconds

The following chart shows the distance of Comet 77P/Longmore 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 77P/Longmore 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 77P/Longmore from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet 77P/Longmore to Earth

Between January 2013 and December 2100, the closest approach of Comet 77P/Longmore to Earth happens on Sun Apr 22 2063 at a distance of 1.005962 Astronomical Units, or 150,489,794 kilometers:

Sun Apr 22 2063

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

Comet 77P/Longmore brightness

The current visual magnitude of Comet 77P/Longmore is 19.01.


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 77P/Longmore, 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 77P/Longmore between January 2013 and December 2100

Comet 77P/Longmore rise and set times

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

Comet 77P/Longmore is circumpolar and transits at 16:13 UTC (altitude: 79.5°)

The rise and set times are defined as the time at which the upper limb of Comet 77P/Longmore 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 77P/Longmore Orbital Elements

The following table lists the orbital elements of Comet 77P/Longmore at epoch 22 December 2010 00:00 UTC (JD: 2455553.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.35771105
Orbit inclination i 24.40067420°
Perihelion distance q 2.31291378 AU
346,006,977 km
Aphelion distance Q 4.88918354 AU
731,411,449 km
Semi-major axis a 3.60104866 AU
538,709,213 km
Orbital period period 6.8336 years
2,495.9847 days
Date of perihelion transit Tp 2009-Jul-08 02:07:09
2,455,020.5883 JD
Next perihelion transit 2016-May-08 01:45
2,457,516.5730 JD
Argument of perihelion peri 196.84236777537°
Longitude of the ascending node node 14.908258861823°
Mean anomaly M 76.862735844051°
Mean motion n 0.14423166°/day

Visualization of Comet 77P/Longmore Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet 77P/Longmore with respect of the Sun and the orbits of the major planets. The position of Comet 77P/Longmore 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 77P/Longmore
View Comet 77P/Longmore in the 3D Solar System Simulator

Comet 77P/Longmore 15 Days Ephemeris

The following table lists the ephemerides of Comet 77P/Longmore computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet 77P/Longmore in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2022 May 09 07h 40m 31s +42° 08’ 25” 19.03 Lynx
2022 May 10 07h 41m 53s +41° 59’ 30” 19.03 Lynx
2022 May 11 07h 43m 15s +41° 50’ 34” 19.02 Lynx
2022 May 12 07h 44m 39s +41° 41’ 36” 19.02 Lynx
2022 May 13 07h 46m 03s +41° 32’ 39” 19.02 Lynx
2022 May 14 07h 47m 27s +41° 23’ 39” 19.02 Lynx
2022 May 15 07h 48m 52s +41° 14’ 39” 19.02 Lynx
2022 May 16 07h 50m 18s +41° 05’ 36” 19.01 Lynx
2022 May 17 07h 51m 44s +40° 56’ 34” 19.01 Lynx
2022 May 18 07h 53m 11s +40° 47’ 29” 19.01 Lynx
2022 May 19 07h 54m 38s +40° 38’ 22” 19.01 Lynx
2022 May 20 07h 56m 05s +40° 29’ 14” 19.01 Lynx
2022 May 21 07h 57m 33s +40° 20’ 06” 19.00 Lynx
2022 May 22 07h 59m 02s +40° 10’ 55” 19.00 Lynx