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🌎  Greenwich, United Kingdom [change]

Comet 27P/Crommelin

Comet 27P/Crommelin is currently in the constellation of Ophiucus. The current Right Ascension of Comet 27P/Crommelin is 17h 17m 52s and the Declination is -18° 04’ 59” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet 27P/Crommelin is 53.43 (JPL).

Summary of key facts about Comet 27P/Crommelin [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]:

17h 17m 52s
-18° 04’ 59”
  • 27P/Crommelin is above the horizon from Greenwich, United Kingdom [change].
  • It is visible looking in the East-South-East direction at an altitude of 1° above the horizon.
  • Given its current magnitude, 27P/Crommelin is visible only through long exposure photography.
  • See also 27P/Crommelin 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 27P/Crommelin available on TheSkyLive:

Available Resources

Comet 27P/Crommelin Position and Finder Charts

Below we provide Comet 27P/Crommelin 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 27P/Crommelin in Ophiucus on December, 09 2021
Field of view: 50x30 degrees
View fullscreen
Map showing Comet 27P/Crommelin in Ophiucus on December, 09 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 27P/Crommelin is right now. Click on the image to see a more detailed fullscreen tracker view.

RA: 17h 17m 52s
Dec: -18° 04’ 59”
Deep sky finder chart for Comet 27P/Crommelin
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet 27P/Crommelin?, a page that provides all the information needed to find Comet 27P/Crommelin in the sky and additional links to sky charts.

Comet 27P/Crommelin Distance from Earth

The distance of Comet 27P/Crommelin from Earth is currently 2,672,709,617 kilometers, equivalent to 17.865960 Astronomical Units. Light takes 2 hours, 28 minutes and 35.1997 seconds to travel from Comet 27P/Crommelin and arrive to us.

2 hours, 28 minutes and 35.1997 seconds

The following chart shows the distance of Comet 27P/Crommelin 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 27P/Crommelin 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 27P/Crommelin from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet 27P/Crommelin to Earth

Between January 2013 and December 2100, the closest approach of Comet 27P/Crommelin to Earth happens on Thu Jul 8 2066 at a distance of 1.663966 Astronomical Units, or 248,925,805 kilometers:

Thu Jul 8 2066

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

Comet 27P/Crommelin brightness

The current visual magnitude of Comet 27P/Crommelin is 53.43.


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 27P/Crommelin, 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 27P/Crommelin between January 2013 and December 2100

Comet 27P/Crommelin 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 27P/Crommelin rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 108.1°
Max altitude: 20.4°
Azimuth: 251.9°

The rise and set times are defined as the time at which the upper limb of Comet 27P/Crommelin 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 27P/Crommelin Orbital Elements

The following table lists the orbital elements of Comet 27P/Crommelin at epoch 12 March 2013 00:00 UTC (JD: 2456364.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.91898109
Orbit inclination i 28.96687279°
Perihelion distance q 0.74828747 AU
111,942,212 km
Aphelion distance Q 17.72363442 AU
2,651,417,976 km
Semi-major axis a 9.23596094 AU
1,381,680,094 km
Orbital period period 28.0693 years
10,252.3060 days
Date of perihelion transit Tp 2011-Aug-03 21:23:10
2,455,777.3911 JD
Next perihelion transit 2039-Aug-29 04:43
2,466,029.6971 JD
Argument of perihelion peri 196.02539689138°
Longitude of the ascending node node 250.62640983902°
Mean anomaly M 20.615772516836°
Mean motion n 0.03511405°/day

Visualization of Comet 27P/Crommelin Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet 27P/Crommelin with respect of the Sun and the orbits of the major planets. The position of Comet 27P/Crommelin 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 27P/Crommelin
View Comet 27P/Crommelin in the 3D Solar System Simulator

Comet 27P/Crommelin 15 Days Ephemeris

The following table lists the ephemerides of Comet 27P/Crommelin computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet 27P/Crommelin in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2021 Dec 02 17h 16m 02s -18° 03’ 39” 53.42 Ophiucus
2021 Dec 03 17h 16m 18s -18° 03’ 51” 53.42 Ophiucus
2021 Dec 04 17h 16m 32s -18° 04’ 02” 53.43 Ophiucus
2021 Dec 05 17h 16m 48s -18° 04’ 14” 53.43 Ophiucus
2021 Dec 06 17h 17m 03s -18° 04’ 24” 53.43 Ophiucus
2021 Dec 07 17h 17m 17s -18° 04’ 36” 53.43 Ophiucus
2021 Dec 08 17h 17m 33s -18° 04’ 45” 53.43 Ophiucus
2021 Dec 09 17h 17m 48s -18° 04’ 55” 53.43 Ophiucus
2021 Dec 10 17h 18m 02s -18° 05’ 04” 53.43 Ophiucus
2021 Dec 11 17h 18m 17s -18° 05’ 13” 53.43 Ophiucus
2021 Dec 12 17h 18m 33s -18° 05’ 22” 53.43 Ophiucus
2021 Dec 13 17h 18m 47s -18° 05’ 30” 53.44 Ophiucus
2021 Dec 14 17h 19m 02s -18° 05’ 39” 53.44 Ophiucus
2021 Dec 15 17h 19m 18s -18° 05’ 47” 53.44 Ophiucus