Comet 77P/Longmore

Comet 77P/Longmore is currently in the constellation of Perseus. The current Right Ascension of Comet 77P/Longmore is 04h 23m 42s and the Declination is +39° 28’ 03” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet 77P/Longmore is 21.75 (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]:

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Additional information about Comet 77P/Longmore available on TheSkyLive:

Available Resources

• Position and finder charts (see also Where is Comet 77P/Longmore?)
• Distance from Earth (see also How far is Comet 77P/Longmore from Earth?)
• Rise and set times (see also When does Comet 77P/Longmore rise and set?)
• Brightness (see also How bright is Comet 77P/Longmore?)
• Orbital elements. Detailed information about Comet 77P/Longmore orbital parameters.
• Interactive orbit visualization. 3d visualization showing the orbit of Comet 77P/Longmore with respect to the major Solar System objects.
• 15 days ephemerides. Table showing celestial coordinates and magnitude of Comet 77P/Longmore for the past and next 7 days.
• Interactive sky chart. An online planetarium application that shows where to locate Comet 77P/Longmore in the sky from your location.
• Live position tracker. A high precision sky chart that uses real deep sky imagery to help locate Comet 77P/Longmore with your telescope or on your astrophotographies.

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.

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 760,549,605 kilometers, equivalent to 5.083960 Astronomical Units. Light takes 42 minutes and 16.9204 seconds to travel from Comet 77P/Longmore and arrive to us.

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.

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 1.005967 Astronomical Units, or 150,490,463 kilometers:

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 21.75.

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.

Comet 77P/Longmore rise and set times

Comet 77P/Longmore is circumpolar and transits at 13:01 UTC (altitude: 78.0°)

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.

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!

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
2021 May 05	04h 13m 56s	+39° 09’ 51”	21.77	Perseus
2021 May 06	04h 15m 14s	+39° 12’ 15”	21.77	Perseus
2021 May 07	04h 16m 32s	+39° 14’ 39”	21.76	Perseus
2021 May 08	04h 17m 48s	+39° 17’ 04”	21.76	Perseus
2021 May 09	04h 19m 06s	+39° 19’ 30”	21.76	Perseus
2021 May 10	04h 20m 26s	+39° 21’ 56”	21.76	Perseus
2021 May 11	04h 21m 43s	+39° 24’ 23”	21.76	Perseus
2021 May 12	04h 23m 03s	+39° 26’ 49”	21.75	Perseus
2021 May 13	04h 24m 23s	+39° 29’ 17”	21.75	Perseus
2021 May 14	04h 25m 41s	+39° 31’ 45”	21.75	Perseus
2021 May 15	04h 27m 02s	+39° 34’ 14”	21.75	Perseus
2021 May 16	04h 28m 22s	+39° 36’ 42”	21.74	Perseus
2021 May 17	04h 29m 43s	+39° 39’ 11”	21.74	Perseus
2021 May 18	04h 31m 03s	+39° 41’ 42”	21.74	Perseus