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🌎  Greenwich, United Kingdom [change]

Comet C/2021 P4 (ATLAS)

Comet C/2021 P4 (ATLAS) is currently in the constellation of Lacerta. The current Right Ascension of Comet C/2021 P4 (ATLAS) is 22h 31m 07s and the Declination is +56° 24’ 55” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet C/2021 P4 (ATLAS) is 17.14 (JPL) while the latest observed magnitude is 17.7 (COBS).

Summary of key facts about Comet C/2021 P4 (ATLAS) [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]:

22h 31m 07s
+56° 24’ 55”
Lacerta
17.7
17.14
  • C/2021 P4 (ATLAS) is above the horizon from Greenwich, United Kingdom [change].
  • It is visible looking in the West-North-West direction at an altitude of 62° above the horizon.
  • Given its current magnitude, C/2021 P4 (ATLAS) is visible only through long exposure photography.
  • See also C/2021 P4 (ATLAS) 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 C/2021 P4 (ATLAS) available on TheSkyLive:

Available Resources

Comet C/2021 P4 (ATLAS) Position and Finder Charts

Below we provide Comet C/2021 P4 (ATLAS) 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 C/2021 P4 (ATLAS) in Lacerta on December, 04 2021
Field of view: 50x30 degrees
View fullscreen
Map showing Comet C/2021 P4 (ATLAS) in Lacerta on December, 04 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 C/2021 P4 (ATLAS) is right now. Click on the image to see a more detailed fullscreen tracker view.

C/2021 P4 (ATLAS)
RA: 22h 31m 07s
Dec: +56° 24’ 55”
Deep sky finder chart for Comet C/2021 P4 (ATLAS)
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet C/2021 P4 (ATLAS)?, a page that provides all the information needed to find Comet C/2021 P4 (ATLAS) in the sky and additional links to sky charts.

Comet C/2021 P4 (ATLAS) Distance from Earth

The distance of Comet C/2021 P4 (ATLAS) from Earth is currently 454,624,560 kilometers, equivalent to 3.038977 Astronomical Units. Light takes 25 minutes and 16.4643 seconds to travel from Comet C/2021 P4 (ATLAS) and arrive to us.

454,624,560
3.038977
25 minutes and 16.4643 seconds

The following chart shows the distance of Comet C/2021 P4 (ATLAS) 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 C/2021 P4 (ATLAS) from Earth between January 2014 and January 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 C/2021 P4 (ATLAS) from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet C/2021 P4 (ATLAS) to Earth

Between January 2014 and January 2100, the closest approach of Comet C/2021 P4 (ATLAS) to Earth happens on Wed Jul 13 2022 at a distance of 1.958002 Astronomical Units, or 292,912,937 kilometers:

Wed Jul 13 2022
292,912,937
1.958002

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

Comet C/2021 P4 (ATLAS) brightness

The current visual magnitude of Comet C/2021 P4 (ATLAS) is 17.14.

17.14
17.7
0.4'

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 C/2021 P4 (ATLAS), 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 C/2021 P4 (ATLAS) between January 2014 and January 2100

Comet C/2021 P4 (ATLAS) rise and set times

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

Comet C/2021 P4 (ATLAS) is circumpolar and transits at 17:36 UTC (altitude: 85.1°)

The rise and set times are defined as the time at which the upper limb of Comet C/2021 P4 (ATLAS) 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 C/2021 P4 (ATLAS) Orbital Elements

The following table lists the orbital elements of Comet C/2021 P4 (ATLAS) at epoch 21 September 2021 00:00 UTC (JD: 2459479.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.99645717
Orbit inclination i 56.31146489°
Perihelion distance q 1.08046893 AU
161,635,851 km
Aphelion distance Q 608.86621605 AU
91,085,089,645 km
Semi-major axis a 304.97334249 AU
45,623,362,748 km
Orbital period period 5,325.9983 years
1,945,320.8711 days
Date of perihelion transit Tp 2022-Jul-30 09:37:28
2,459,790.9010 JD
Argument of perihelion peri 175.8267980647°
Longitude of the ascending node node 348.09579046065°
Mean anomaly M 359.94237229875°
Mean motion n 0.00018506°/day

Visualization of Comet C/2021 P4 (ATLAS) Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet C/2021 P4 (ATLAS) with respect of the Sun and the orbits of the major planets. The position of Comet C/2021 P4 (ATLAS) 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/2021 P4 (ATLAS)
View Comet C/2021 P4 (ATLAS) in the 3D Solar System Simulator

Comet C/2021 P4 (ATLAS) 15 Days Ephemeris

The following table lists the ephemerides of Comet C/2021 P4 (ATLAS) computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet C/2021 P4 (ATLAS) in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2021 Nov 27 22h 33m 57s +57° 46’ 12” 17.29 Cepheus
2021 Nov 28 22h 33m 28s +57° 35’ 47” 17.27 Cepheus
2021 Nov 29 22h 33m 00s +57° 25’ 22” 17.25 Cepheus
2021 Nov 30 22h 32m 35s +57° 14’ 58” 17.23 Cepheus
2021 Dec 01 22h 32m 12s +57° 04’ 36” 17.21 Cepheus
2021 Dec 02 22h 31m 53s +56° 54’ 16” 17.20 Cepheus
2021 Dec 03 22h 31m 35s +56° 43’ 59” 17.18 Lacerta
2021 Dec 04 22h 31m 18s +56° 33’ 44” 17.16 Lacerta
2021 Dec 05 22h 31m 05s +56° 23’ 35” 17.14 Lacerta
2021 Dec 06 22h 30m 56s +56° 13’ 27” 17.12 Lacerta
2021 Dec 07 22h 30m 47s +56° 03’ 25” 17.10 Lacerta
2021 Dec 08 22h 30m 41s +55° 53’ 29” 17.08 Lacerta
2021 Dec 09 22h 30m 38s +55° 43’ 36” 17.06 Lacerta
2021 Dec 10 22h 30m 36s +55° 33’ 51” 17.04 Lacerta