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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 6:43  
clear_day Transit: 12:51  
SunsetSet: 18:59 south
sunny DaytimeWhat's Visible Now
Comets » 

Comet C/2021 S3 (PANSTARRS)

Altitude: -22.0°   Azimuth: 247.6°   Direction: West-South-West

Comet C/2021 S3 (PANSTARRS) is currently in the constellation of Antlia. The current Right Ascension of Comet C/2021 S3 (PANSTARRS) is 09h 39m 56s and the Declination is -30° 55’ 54” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom edit_location_alt). The current estimated magnitude of Comet C/2021 S3 (PANSTARRS) is 11.46 (JPL).

09h 39m 56s
-30° 55’ 54”

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 edit_location_alt (all times relative to the local timezone Europe/London):

Azimuth: 120.9°
Max altitude: 7.6°
Azimuth: 239.1°
  • C/2021 S3 (PANSTARRS) is below the horizon from Greenwich, United Kingdom edit_location_alt.
  • Given its current magnitude, C/2021 S3 (PANSTARRS) is visible with the help of a telescope having an aperture of 6 inches (150mm) 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.

Available Resources

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

Below we provide Comet C/2021 S3 (PANSTARRS) 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.

Finder chart of C/2021 S3 (PANSTARRS) in Antlia on September,21 2023
Map showing Comet C/2021 S3 (PANSTARRS) in Antlia on September, 21 2023
Field of view: 50x30 degrees
View fullscreen
Finder chart of C/2021 S3 (PANSTARRS)
Map showing Comet C/2021 S3 (PANSTARRS) in Antlia on September, 21 2023
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: 09h 39m 56s
Dec: -30° 55’ 54”
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 454,083,272 kilometers, equivalent to 3.035359 Astronomical Units. Light takes 25 minutes and 14.6588 seconds to travel from Comet C/2021 S3 (PANSTARRS) and arrive to us.

25 minutes and 14.6588 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
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
2023 Sep 14 09h 22m 23s -29° 46’ 50” 11.67 Pyxis
2023 Sep 15 09h 24m 38s -29° 55’ 41” 11.64 Pyxis
2023 Sep 16 09h 26m 54s -30° 04’ 33” 11.61 Pyxis
2023 Sep 17 09h 29m 12s -30° 13’ 32” 11.59 Antlia
2023 Sep 18 09h 31m 28s -30° 22’ 32” 11.56 Antlia
2023 Sep 19 09h 33m 47s -30° 31’ 36” 11.53 Antlia
2023 Sep 20 09h 36m 06s -30° 40’ 45” 11.51 Antlia
2023 Sep 21 09h 38m 26s -30° 49’ 55” 11.48 Antlia
2023 Sep 22 09h 40m 46s -30° 59’ 09” 11.45 Antlia
2023 Sep 23 09h 43m 08s -31° 08’ 26” 11.43 Antlia
2023 Sep 24 09h 45m 29s -31° 17’ 44” 11.40 Antlia
2023 Sep 25 09h 47m 53s -31° 27’ 06” 11.37 Antlia
2023 Sep 26 09h 50m 16s -31° 36’ 29” 11.34 Antlia
2023 Sep 27 09h 52m 41s -31° 45’ 55” 11.32 Antlia