Comet C/2017 K2 (PANSTARRS) is a comet that was discovered on May 21, 2017, by the Pan-STARRS telescope in Hawaii. It has a hyperbolic orbit with a high inclination with respect to the ecliptic plane (close to 90°), indicating that it likely originated from the Oort Cloud. Its closest approach to the Sun, or perihelion, occurred on December 19, 2022, at a distance of 1.8 astronomical units (AU), and it reached its maximum brightness between December 2022 and February 2023. After perihelion, it is slowly becoming fainter as it continues on its journey back to the outer reaches of the solar system.

Find it in the Sky

Chose a date & time and view the position of Comet C/2017 K2 (PANSTARRS) in the sky on our interactive planetarium.

Time: : UTC

Comets »

Comet C/2017 K2 (PANSTARRS)

Above the horizon. Rise: 6:17 | Tran: 14:40 | Set: 23:03

Alt: 17.64° Az: 288.69° Direction: West-North-West

Comet C/2017 K2 (PANSTARRS) is in the constellation of Taurus, at a distance of 1,438,240,995.0 kilometers from Earth. The current Right Ascension is 05h 42m 04s and the Declination is +25° 17’ 31” (apparent coordinates). The predicted magnitude of Comet C/2017 K2 (PANSTARRS) is 17.74 (data provided by JPL Horizons).

Finder Charts

Loading map...

Map showing Comet C/2017 K2 (PANSTARRS) in Taurus on May, 22 2025. Field of view: 50x30 degrees
View interactive star map

Loading map...

Sky map showing Comet C/2017 K2 (PANSTARRS) in Taurus on May, 22 2025. Field of view: 15x9 degrees. View in interactive sky chart

High precision deep sky finder chart, 60 arcmin wide, showing where Comet C/2017 K2 (PANSTARRS) is right now. Click on the image to see a more detailed fullscreen tracker view.

C/2017 K2 (PANSTARRS)
RA: 05h 40m 30s
Dec: +25° 16’ 50”

Deep sky finder chart for Comet C/2017 K2 (PANSTARRS). Field of view: 60x40 arcmins. View in deep sky object tracker

Also check out Where is Comet C/2017 K2 (PANSTARRS)?, a page that provides all the information needed to find Comet C/2017 K2 (PANSTARRS) in the sky and additional links to sky charts.

Celestial Coordinates

Apparent

Right Ascension 05h 42m 04s

Declination +25° 17’ 31”

Hour Angle 06h 12m 43s

Sidereal Time 11h 54m 48s

J2000

Right Ascension 05h 40m 30s

Declination +25° 16’ 50”

Additional Information

Constellation Taurus

Observed Magnitude (COBS) n/a

Coma Diameter (COBS) n/a

Tail Length (COBS) n/a

Observation Date (COBS) n/a

Predicted Magnitude (JPL) 17.74

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.

Rise and Set Times

Today's rise, transit and set times of Comet C/2017 K2 (PANSTARRS) from Greenwich, UK (all times relative to the local timezone Europe/London):

Azimuth: 64.7° RISE 6:17

Max altitude: 63.8° TRANSIT 14:40

Azimuth: 295.3° SET 23:03

VISIBILITY RIGHT NOW

C/2017 K2 (PANSTARRS) is above the horizon from Greenwich, UK.
Right now it is placed in the West-North-West direction at an altitude of 17.64° above the horizon.
Given its current magnitude, C/2017 K2 (PANSTARRS) is visible only through long exposure photography.
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.

Distance from Earth

The distance of Comet C/2017 K2 (PANSTARRS) from Earth is currently 1,438,240,995.0 kilometers, equivalent to 9.6140472339 Astronomical Units. Light takes 1h 19m 57.456s to travel from Comet C/2017 K2 (PANSTARRS) and arrive to us.

Distance Km 1,438,240,995.0

Distance AU 9.6140472339

Light Travel Time 1h 19m 57.456s

The following chart shows the distance of Comet C/2017 K2 (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/2017 K2 (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/2017 K2 (PANSTARRS) from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest Approach

Between 1 January 2000 and 31 December 2099, the closest approach of Comet C/2017 K2 (PANSTARRS) to Earth happens on Thu Jul 14 2022 at a distance of 1.807997 Astronomical Units, or 270,472,476 kilometers:

Date Thu Jul 14 2022

Distance Kilometers 270,472,476

Distance AU 1.807997

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

Light Curve

The following chart is the predicted light curve (visual magnitude as a function of time) of Comet C/2017 K2 (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/2017 K2 (PANSTARRS) as a function of time

Orbital Elements

The following table lists the orbital elements of Comet C/2017 K2 (PANSTARRS) at epoch 03 June 2021 00:00 UTC (JD: 2459369.5). Source: JPL Small-Body Database

Element	Symbol	Value
Orbit eccentricity	e	1.00056078
Orbit inclination	i	87.55243451°
Perihelion distance	q	1.79758614 AU 268,915,059 km
Aphelion distance	Q	n.a.
Semi-major axis	a	n.a.
Orbital period	period	n.a.
Date of perihelion transit	Tp	2022-Dec-19 18:20:10 2,459,933.2640 JD
Argument of perihelion	peri	236.18815747°
Longitude of the ascending node	node	88.24466059559°
Mean anomaly	M	-0.0030616420406343°
Mean motion	n	0.00000543°/day

2h1>Orbit Visualization

Orbit Diagram of Comet C/2017 K2 (PANSTARRS)
View Comet C/2017 K2 (PANSTARRS) in the 3D Solar System Simulator

15 Days Ephemeris

The following table lists the ephemerides of Comet C/2017 K2 (PANSTARRS) computed for the past and next 7 days, with a 24 hours interval. Apparent celestial coordinates are provided.

Date	Right AscensionR.A.	DeclinationDec.	MagnitudeMag	Constellation
2025 May 15	05h 38m 52s	+25° 06’ 06”	17.70	Taurus
2025 May 16	05h 39m 16s	+25° 07’ 34”	17.71	Taurus
2025 May 17	05h 39m 41s	+25° 09’ 03”	17.71	Taurus
2025 May 18	05h 40m 05s	+25° 10’ 31”	17.72	Taurus
2025 May 19	05h 40m 29s	+25° 11’ 58”	17.72	Taurus
2025 May 20	05h 40m 54s	+25° 13’ 25”	17.73	Taurus
2025 May 21	05h 41m 19s	+25° 14’ 52”	17.73	Taurus
2025 May 22	05h 41m 43s	+25° 16’ 19”	17.74	Taurus
2025 May 23	05h 42m 09s	+25° 17’ 46”	17.74	Taurus
2025 May 24	05h 42m 34s	+25° 19’ 12”	17.75	Taurus
2025 May 25	05h 43m 00s	+25° 20’ 38”	17.75	Taurus
2025 May 26	05h 43m 25s	+25° 22’ 03”	17.76	Taurus
2025 May 27	05h 43m 50s	+25° 23’ 29”	17.76	Taurus
2025 May 28	05h 44m 16s	+25° 24’ 54”	17.77	Taurus

Ephemeris Calculator

Compute the position of Comet C/2017 K2 (PANSTARRS) for any date and time between 1 January 2000 and 31 December 2099 and display the results on an interactive star map.