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public LocationGreenwich, United Kingdom
Sunrise: 4:42 
Transit: 13:00 
Sunset: 21:17
sunny   (Daytime)   What's Visible Now?

Comet C/2021 S3 (PANSTARRS)

Above the horizon.  Circumpolar today
Altitude: 74.6°   Azimuth: 316.6°   Direction: North-West

Comet C/2021 S3 (PANSTARRS) is currently in the constellation of Cepheus, at a distance of 293,876,695 kilometers from Earth. The current Right Ascension of Comet C/2021 S3 (PANSTARRS) is 20h 26m 36s and the Declination is +60° 59’ 48” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom). The current estimated magnitude of Comet C/2021 S3 (PANSTARRS) is 10.12 (JPL) while the latest observed magnitude is 11.9 (COBS).

Finder chart of C/2021 S3 (PANSTARRS) in Cepheus on June,19 2024
Map showing Comet C/2021 S3 (PANSTARRS) in Cepheus on June, 19 2024. Field of view: 50x30 degrees
View interactive star map

20h 26m 36s
+60° 59’ 48”

The observed values of Magnitude, Coma Diameter and Tail Length are derived from the most recent observation recorded at the Comet Observers Database. The value of Predicted Magnitude comes from the JPL Horizons ephemerides service and, in the case of comets, might be inaccurate given the highly dynamic and unpredictable behavior of these objects. When available, please refer to the Observed Magnitude value and consider the Predicted 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.

Today's rise, transit and set times of Comet C/2021 S3 (PANSTARRS) from Greenwich, United Kingdom (all times relative to the local timezone Europe/London):

Today Comet C/2021 S3 (PANSTARRS) is circumpolar and transits at 02:35 UTC reaching a maximum altitude of 80.5°.
  • C/2021 S3 (PANSTARRS) is above the horizon from Greenwich, United Kingdom.
  • Right now it is placed in the North-West direction at an altitude of 75° above the horizon.
  • Given its current magnitude, C/2021 S3 (PANSTARRS) is visible with the help of a telescope having an aperture of 8 inches (200mm) or more.
  • 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 Resources

Comet C/2021 S3 (PANSTARRS) Position and Finder Charts

Finder chart of C/2021 S3 (PANSTARRS)
Map showing Comet C/2021 S3 (PANSTARRS) in Cepheus on June, 19 2024
Field of view: 10x6 degrees
View fullscreen

Higher precision deep sky finder chart, 60 arcmin wide, showing where Comet C/2021 S3 (PANSTARRS) is right now. Click on the image to see a more detailed fullscreen tracker view.

RA: 20h 26m 36s
Dec: +60° 59’ 48”
Deep sky finder chart for Comet C/2021 S3 (PANSTARRS)
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet C/2021 S3 (PANSTARRS)?, a page that provides all the information needed to find Comet C/2021 S3 (PANSTARRS) in the sky and additional links to sky charts.

Comet C/2021 S3 (PANSTARRS) Distance from Earth

The distance of Comet C/2021 S3 (PANSTARRS) from Earth is currently 293,876,695 kilometers, equivalent to 1.964444 Astronomical Units. Light takes 16 minutes and 20.2671 seconds to travel from Comet C/2021 S3 (PANSTARRS) and arrive to us.

16 minutes and 20.2671 seconds

The following chart shows the distance of Comet C/2021 S3 (PANSTARRS) 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.

Chart of the distance of Comet C/2021 S3 (PANSTARRS) from Earth in Astronomical Units (au)

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 S3 (PANSTARRS) from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest Approach of Comet C/2021 S3 (PANSTARRS) to Earth

Between 1 January 2013 and 30 December 2100, the closest approach of Comet C/2021 S3 (PANSTARRS) to Earth happens on Fri Mar 15 2024 at a distance of 1.297933 Astronomical Units, or 194,167,957 kilometers:

Fri Mar 15 2024

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

Comet C/2021 S3 (PANSTARRS) Brightness and Light Curve

The following chart is the predicted light curve (visual magnitude as a function of time) of Comet C/2021 S3 (PANSTARRS), 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.

Chart of the magnitude of Comet C/2021 S3 (PANSTARRS) as a function of time

Comet C/2021 S3 (PANSTARRS) Orbital Elements

The following table lists the orbital elements of Comet C/2021 S3 (PANSTARRS) at epoch 27 September 2022 00:00 UTC (JD: 2459850.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.99990918
Orbit inclination i 58.53533581°
Perihelion distance q 1.31952176 AU
197,397,646 km
Aphelion distance Q 29,057.43050524 AU
4,346,929,740,314 km
Semi-major axis a 14,529.37501350 AU
2,173,563,568,980 km
Orbital period period 1,751,372.8071 years
639,688,917.8025 days
Date of perihelion transit Tp 2024-Feb-14 18:17:22
2,460,355.2621 JD
Next perihelion transit 4214-Jul-12 16:13
642,149,273.0646 JD
Argument of perihelion peri 6.8874262186992°
Longitude of the ascending node node 215.62759532093°
Mean anomaly M 359.99971593326°
Mean motion n 0.00000056°/day

Visualization of Comet C/2021 S3 (PANSTARRS) Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet C/2021 S3 (PANSTARRS) with respect of the Sun and the orbits of the major planets. The position of Comet C/2021 S3 (PANSTARRS) 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 S3 (PANSTARRS)
View Comet C/2021 S3 (PANSTARRS) in the 3D Solar System Simulator

Comet C/2021 S3 (PANSTARRS) 15 Days Ephemeris

The following table lists the ephemerides of Comet C/2021 S3 (PANSTARRS) 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 S3 (PANSTARRS) in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2024 Jun 12 20h 32m 17s +59° 33’ 32” 9.90 Cygnus
2024 Jun 13 20h 31m 36s +59° 47’ 02” 9.93 Cygnus
2024 Jun 14 20h 30m 55s +60° 00’ 02” 9.96 Cepheus
2024 Jun 15 20h 30m 10s +60° 12’ 36” 9.99 Cepheus
2024 Jun 16 20h 29m 22s +60° 24’ 41” 10.02 Cepheus
2024 Jun 17 20h 28m 32s +60° 36’ 16” 10.05 Cepheus
2024 Jun 18 20h 27m 39s +60° 47’ 25” 10.08 Cepheus
2024 Jun 19 20h 26m 45s +60° 58’ 03” 10.11 Cepheus
2024 Jun 20 20h 25m 49s +61° 08’ 12” 10.14 Cepheus
2024 Jun 21 20h 24m 50s +61° 17’ 53” 10.17 Cepheus
2024 Jun 22 20h 23m 48s +61° 27’ 06” 10.19 Cepheus
2024 Jun 23 20h 22m 45s +61° 35’ 49” 10.22 Cepheus
2024 Jun 24 20h 21m 39s +61° 44’ 04” 10.25 Cepheus
2024 Jun 25 20h 20m 31s +61° 51’ 51” 10.28 Cepheus