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🌎  Greenwich, United Kingdom [change]

Comet C/2019 Q4 (Borisov)

Comet C/2019 Q4 (Borisov) is currently in the constellation of Ara. The current Right Ascension of Comet C/2019 Q4 (Borisov) is 16h 57m 44s and the Declination is -55° 48’ 04” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet C/2019 Q4 (Borisov) is 24.74 (JPL).

Summary of key facts about Comet C/2019 Q4 (Borisov) [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]:

16h 57m 44s
-55° 48’ 04”

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/2019 Q4 (Borisov) available on TheSkyLive:

Available Resources

Comet C/2019 Q4 (Borisov) Position and Finder Charts

Below we provide Comet C/2019 Q4 (Borisov) 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/2019 Q4 (Borisov) in Ara on October, 26 2021
Field of view: 50x30 degrees
View fullscreen
Map showing Comet C/2019 Q4 (Borisov) in Ara on October, 26 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/2019 Q4 (Borisov) is right now. Click on the image to see a more detailed fullscreen tracker view.

C/2019 Q4 (Borisov)
RA: 16h 57m 44s
Dec: -55° 48’ 04”
Deep sky finder chart for Comet C/2019 Q4 (Borisov)
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet C/2019 Q4 (Borisov)?, a page that provides all the information needed to find Comet C/2019 Q4 (Borisov) in the sky and additional links to sky charts.

Comet C/2019 Q4 (Borisov) Distance from Earth

The distance of Comet C/2019 Q4 (Borisov) from Earth is currently 2,212,820,646 kilometers, equivalent to 14.791792 Astronomical Units. Light takes 2 hours, 3 minutes and 1.1752 seconds to travel from Comet C/2019 Q4 (Borisov) and arrive to us.

2 hours, 3 minutes and 1.1752 seconds

The following chart shows the distance of Comet C/2019 Q4 (Borisov) 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/2019 Q4 (Borisov) 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 C/2019 Q4 (Borisov) from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet C/2019 Q4 (Borisov) to Earth

Between January 2013 and December 2100, the closest approach of Comet C/2019 Q4 (Borisov) to Earth happens on Sat Dec 28 2019 at a distance of 1.936750 Astronomical Units, or 289,733,622 kilometers:

Sat Dec 28 2019

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

Comet C/2019 Q4 (Borisov) brightness

The current visual magnitude of Comet C/2019 Q4 (Borisov) is 24.74.


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/2019 Q4 (Borisov), 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/2019 Q4 (Borisov) between January 2013 and December 2100

Comet C/2019 Q4 (Borisov) rise and set times

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

Comet C/2019 Q4 (Borisov) is currently not visible from Greenwich, United Kingdom [change]

The rise and set times are defined as the time at which the upper limb of Comet C/2019 Q4 (Borisov) 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/2019 Q4 (Borisov) 15 Days Ephemeris

The following table lists the ephemerides of Comet C/2019 Q4 (Borisov) computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet C/2019 Q4 (Borisov) in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2021 Oct 19 16h 54m 18s -55° 58’ 58” 24.69 Ara
2021 Oct 20 16h 54m 45s -55° 57’ 24” 24.70 Ara
2021 Oct 21 16h 55m 12s -55° 55’ 53” 24.70 Ara
2021 Oct 22 16h 55m 38s -55° 54’ 24” 24.71 Ara
2021 Oct 23 16h 56m 07s -55° 52’ 55” 24.72 Ara
2021 Oct 24 16h 56m 35s -55° 51’ 29” 24.72 Ara
2021 Oct 25 16h 57m 02s -55° 50’ 06” 24.73 Ara
2021 Oct 26 16h 57m 29s -55° 48’ 43” 24.74 Ara
2021 Oct 27 16h 57m 59s -55° 47’ 23” 24.75 Ara
2021 Oct 28 16h 58m 27s -55° 46’ 05” 24.75 Ara
2021 Oct 29 16h 58m 55s -55° 44’ 48” 24.76 Ara
2021 Oct 30 16h 59m 25s -55° 43’ 33” 24.77 Ara
2021 Oct 31 16h 59m 53s -55° 42’ 20” 24.77 Ara
2021 Nov 01 17h 00m 23s -55° 41’ 08” 24.78 Ara