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Comet C/2021 A4 (NEOWISE)

Comet C/2021 A4 (NEOWISE) is currently in the constellation of Taurus. The current Right Ascension of Comet C/2021 A4 (NEOWISE) is 04h 31m 26s and the Declination is +15° 10’ 25” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet C/2021 A4 (NEOWISE) is 15.74 (JPL) while the latest observed magnitude is 14.1 (COBS).

Summary of key facts about Comet C/2021 A4 (NEOWISE) [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]:

04h 31m 26s
+15° 10’ 25”
  • C/2021 A4 (NEOWISE) is above the horizon from Greenwich, United Kingdom [change].
  • It is visible looking in the East-North-East direction at an altitude of 5° above the horizon.
  • Given its current magnitude, C/2021 A4 (NEOWISE) is visible with the help of a telescope havng an aperture of 14 inches (350mm) or more.
  • See also C/2021 A4 (NEOWISE) 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 A4 (NEOWISE) available on TheSkyLive:

Available Resources

Comet C/2021 A4 (NEOWISE) Position and Finder Charts

Below we provide Comet C/2021 A4 (NEOWISE) 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 A4 (NEOWISE) in Taurus on March, 01 2021
Field of view: 50x30 degrees
View fullscreen
Map showing Comet C/2021 A4 (NEOWISE) in Taurus on March, 01 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 A4 (NEOWISE) is right now. Click on the image to see a more detailed fullscreen tracker view.

C/2021 A4 (NEOWISE)
RA: 04h 31m 26s
Dec: +15° 10’ 25”
Deep sky finder chart for Comet C/2021 A4 (NEOWISE)
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet C/2021 A4 (NEOWISE)?, a page that provides all the information needed to find Comet C/2021 A4 (NEOWISE) in the sky and additional links to sky charts.

Comet C/2021 A4 (NEOWISE) Distance from Earth

The distance of Comet C/2021 A4 (NEOWISE) from Earth is currently 102,622,137 kilometers, equivalent to 0.685987 Astronomical Units. Light takes 5 minutes and 42.3106 seconds to travel from Comet C/2021 A4 (NEOWISE) and arrive to us.

5 minutes and 42.3106 seconds

The following chart shows the distance of Comet C/2021 A4 (NEOWISE) 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 A4 (NEOWISE) 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 A4 (NEOWISE) from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet C/2021 A4 (NEOWISE) to Earth

Between January 2014 and January 2100, the closest approach of Comet C/2021 A4 (NEOWISE) to Earth happens on Fri Feb 12 2021 at a distance of 0.434065 Astronomical Units, or 64,935,252 kilometers:

Fri Feb 12 2021

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

Comet C/2021 A4 (NEOWISE) brightness

The current visual magnitude of Comet C/2021 A4 (NEOWISE) is 15.74.


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 A4 (NEOWISE), 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 A4 (NEOWISE) between January 2014 and January 2100

Comet C/2021 A4 (NEOWISE) 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 C/2021 A4 (NEOWISE) rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 74.8°
Max altitude: 53.3°
Azimuth: 285.8°

The rise and set times are defined as the time at which the upper limb of Comet C/2021 A4 (NEOWISE) 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 A4 (NEOWISE) Orbital Elements

The following table lists the orbital elements of Comet C/2021 A4 (NEOWISE) at epoch 12 January 2021 00:00 UTC (JD: 2459227.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.97457445
Orbit inclination i 111.58298641°
Perihelion distance q 1.14567157 AU
171,390,028 km
Aphelion distance Q 88.97403579 AU
13,310,326,328 km
Semi-major axis a 45.05985368 AU
6,740,858,178 km
Orbital period period 302.4800 years
110,479.8542 days
Date of perihelion transit Tp 2021-Mar-20 00:06:05
2,459,293.5042 JD
Argument of perihelion peri 204.63175110872°
Longitude of the ascending node node 307.07779508793°
Mean anomaly M 359.78492438848°
Mean motion n 0.00325851°/day

Visualization of Comet C/2021 A4 (NEOWISE) Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet C/2021 A4 (NEOWISE) with respect of the Sun and the orbits of the major planets. The position of Comet C/2021 A4 (NEOWISE) 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 A4 (NEOWISE)
View Comet C/2021 A4 (NEOWISE) in the 3D Solar System Simulator

Comet C/2021 A4 (NEOWISE) 15 Days Ephemeris

The following table lists the ephemerides of Comet C/2021 A4 (NEOWISE) 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 A4 (NEOWISE) in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2021 Feb 22 04h 54m 15s +30° 17’ 09” 15.42 Auriga
2021 Feb 23 04h 49m 51s +27° 47’ 08” 15.46 Taurus
2021 Feb 24 04h 46m 00s +25° 26’ 48” 15.50 Taurus
2021 Feb 25 04h 42m 37s +23° 15’ 44” 15.54 Taurus
2021 Feb 26 04h 39m 36s +21° 13’ 28” 15.58 Taurus
2021 Feb 27 04h 36m 54s +19° 19’ 31” 15.63 Taurus
2021 Feb 28 04h 34m 30s +17° 33’ 15” 15.67 Taurus
2021 Mar 01 04h 32m 20s +15° 54’ 07” 15.72 Taurus
2021 Mar 02 04h 30m 24s +14° 21’ 38” 15.76 Taurus
2021 Mar 03 04h 28m 39s +12° 55’ 13” 15.81 Taurus
2021 Mar 04 04h 27m 03s +11° 34’ 23” 15.85 Taurus
2021 Mar 05 04h 25m 37s +10° 18’ 42” 15.90 Taurus
2021 Mar 06 04h 24m 20s +09° 07’ 42” 15.95 Taurus
2021 Mar 07 04h 23m 08s +08° 01’ 04” 15.99 Taurus