Comet 1P/Halley, also known as Halley's Comet, is a well-known periodic comet that returns to the inner solar system about once every 76 years. It has been observed since ancient times, but it was not recognized as a periodic solar system object until its orbit was accurately calculated by Edmund Halley in the 18th century. The comet's nucleus is estimated to be about 15 kilometers in diameter and it is composed of ice, dust, and small rocky particles. When the comet gets close to the Sun, the heat causes the ice to vaporize and create a coma, a cloud of gas and dust around the nucleus, and a long tail that can stretch millions of kilometers into space. Halley's Comet has an aphelion distance of 35.1 astronomical units (AU) from the Sun, at the outer edge of the Kuiper Belt, and a perihelion distance of 0.6 AU, just inside the orbit of Venus. Its last perihelion passage was in 1986. Currently Halley's Comet is close to its aphelion and it is expected to return to the inner solar system in 2061.

Find it in the Sky

Chose a date & time and view the position of comet 1P/Halley in the sky on our interactive planetarium.

Time: : UTC

EnglishItaliano Español

Comets »

Comet 1P/Halley

Above the horizon. Rise: 7:31 | Tran: 13:44 | Set: 19:54

Alt: 26.48° Az: 251.42° Direction: West-South-West

Comet 1P/Halley is in the constellation of Hydra, at a distance of 5,384,226,598.0 kilometers from Earth. The current Right Ascension is 08h 14m 55s and the Declination is +03° 25’ 59” (apparent coordinates). The estimated magnitude of comet 1P/Halley, computed using JPL Horizons's data, is 25.64).

Finder Charts

The sky charts below show, at different resolutions, the position of comet 1P/Halley in the sky. Click on each chart to access the interactive star map tool.

Loading the finder chart...

Star map showing the position of comet 1P/Halley in the constellation of Hydra on F, d Y. Field of view: 50x30 degrees. View interactive star map.

Loading the finder chart...

Star map showing the position of comet 1P/Halley in the constellation of Hydra on F, d Y. Field of view: 15x9 degrees. View in interactive star map.

The following map uses photographic imagery from the Digitized Sky Survey (DSS) to realistically visualize the precise position of comet 1P/Halley against the stars in the background. The horizontal size of the map measures 60 arcminutes. Click on the image to access a more detailed full-screen view.

1P/Halley
RA: 08h 13m 35s
Dec: +03° 30’ 42”

Simplified high-resolution deep sky chart showing the current position of comet 1P/Halley. Field of view: 60 x 40 arcminutes. Go to the dedicated page

Equatorial Coordinates

Apparent

Right Ascension 08h 14m 55s

Declination +03° 25’ 59”

Hour Angle 03h 52m 50s

Sidereal Time 12h 07m 46s

J2000

Right Ascension 08h 13m 35s

Declination +03° 30’ 42”

Additional Information

Constellation Hydra

Observed Magnitude (COBS) n/a

Coma Diameter (COBS) n/a

Tail Length (COBS) n/a

Observation Date (COBS) n/a

Predicted Magnitude (JPL) 25.64

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

The following table lists today's rise, transit and set times of comet 1P/Halley from Xinkou, China (all times relative to the local timezone Asia/Shanghai):

Azimuth: 86.6° RISE 7:31

Max altitude: 54.3° TRANSIT 13:44

Azimuth: 273.4° SET 19:54

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 1P/Halley from Earth is currently 5,384,226,598.0 kilometers, equivalent to 35.9913317804 Astronomical Units. Light takes 4h 59m 19.847s to travel from comet 1P/Halley and arrive to us.

Distance Km 5,384,226,598.0

Distance AU 35.9913317804

Light Travel Time 4h 59m 19.847s

The following graph shows the distance of comet 1P/Halley from Earth as a function of time. In the chart the distance is measured in Astronomical Units and the data is sampled with an interval of 1 day.

Chart of the distance of comet 1P/Halley from Earth in Astronomical Units (au)
Note: The values in this chart may not be entirely accurate around the time of closest approach for objects passing very close to Earth at high speed (e.g., Near-Earth Objects).

The value of the distance of 1P/Halley from Earth is also available as a real time updated value in the live position tracker.

Closest Approach to Earth

In the period between January 1, 1600 and December 30, 2499, the closest approach of comet 1P/Halley to Earth will happen on Saturday 8 May 2134 at a distance of 0.093428 Astronomical Units, or 13,976,613 kilometers:

Date Saturday 8 May 2134

Distance Kilometers 13,976,613

Distance AU 0.093428

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

Light Curve

The following chart shows the light curve of comet 1P/Halley, i.e., its apparent magnitude as a function of time. The curve is calculated using the latest ephemerides provided by JPL Horizons. The magnitude data is sampled with the interval of 2 days. Because of this sampling, inaccuracies may occur for objects that have large variations of brightness over a few days. For comets, large discrepancies can arise between the calculated brightness and the observations due to their highly dynamic, and not always precisely predictable, behavior.

Chart of the magnitude of comet 1P/Halley as a function of time

Orbital Elements

The following table lists the orbital elements of comet 1P/Halley at epoch UTC (JD: 2439857.5). Source: JPL Small-Body Database

Element	Symbol	Value
Orbit eccentricity	e	0.96794279
Orbit inclination	i	162.18787119°
Perihelion distance	q	0.57471580 AU 85,976,260 km
Aphelion distance	Q	35.28091967 AU 5,277,950,470 km
Semi-major axis	a	17.92781774 AU 2,681,963,365 km
Orbital period	period	75.9101 years 27,726.1500 days
Date of perihelion transit	Tp	February 8, 1986 2,446,470.1489 JD
Next perihelion transit		January 6, 2062 2,474,196.2989 JD
Argument of perihelion	peri	112.25779200487°
Longitude of the ascending node	node	59.114482936739°
Mean anomaly	M	274.14049194984°
Mean motion	n	0.01298413°/day

Orbit Visualization

The following chart is a 3D animated visualization of the orbit of comet 1P/Halley relative to the other major objects in the Solar System. You can access more advanced features using our 3D Solar System Viewer.

15 Days Ephemeris

The following table lists the ephemerides of comet 1P/Halley 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
Jun 25 2025	08h 14m 14s	+03° 26’ 46”	25.64	Hydra
Jun 26 2025	08h 14m 20s	+03° 26’ 42”	25.64	Hydra
Jun 27 2025	08h 14m 25s	+03° 26’ 37”	25.64	Hydra
Jun 28 2025	08h 14m 31s	+03° 26’ 32”	25.64	Hydra
Jun 29 2025	08h 14m 36s	+03° 26’ 24”	25.64	Hydra
Jun 30 2025	08h 14m 42s	+03° 26’ 18”	25.64	Hydra
Jul 01 2025	08h 14m 47s	+03° 26’ 11”	25.64	Hydra
Jul 02 2025	08h 14m 53s	+03° 26’ 03”	25.64	Hydra
Jul 03 2025	08h 14m 59s	+03° 25’ 54”	25.64	Hydra
Jul 04 2025	08h 15m 05s	+03° 25’ 45”	25.65	Hydra
Jul 05 2025	08h 15m 10s	+03° 25’ 35”	25.65	Hydra
Jul 06 2025	08h 15m 16s	+03° 25’ 25”	25.65	Hydra
Jul 07 2025	08h 15m 22s	+03° 25’ 15”	25.65	Hydra
Jul 08 2025	08h 15m 28s	+03° 25’ 04”	25.65	Hydra

Ephemeris Calculator

Compute the position of comet 1P/Halley for any date and time between January 1, 1600 and December 30, 2499 and display the results on an interactive star map.