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Comet 117P/Helin-Roman-Alu 1

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Comet 117P/Helin-Roman-Alu 1 Position

Comet 117P/Helin-Roman-Alu 1 is currently in the constellation of Leo. The current Right Ascension is 09h 56m 07s and the Declination is +20° 17’ 54”.

09h 56m 07s
+20° 17’ 54”

Simplified sky chart showing where Comet 117P/Helin-Roman-Alu 1 is right now in the sky with respect to the brightest stars and constellations (see fuillscreen Online Planetarium)

Map showing Comet 117P/Helin-Roman-Alu 1 in Leo on September, 15 2019
Field of view: 60x30 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]

Hihgher precision deep sky finder chart showing where Comet 117P/Helin-Roman-Alu 1 is right now (view fullscreen)

117P/Helin-Roman-Alu 1
RA: 09h 56m 07s
Dec: +20° 17’ 54”
Deep sky finder chart for Comet 117P/Helin-Roman-Alu 1
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet 117P/Helin-Roman-Alu 1?, a page that provides all the information needed to find Comet 117P/Helin-Roman-Alu 1 in the sky and additional links to sky charts.

Comet 117P/Helin-Roman-Alu 1 Distance

The distance of Comet 117P/Helin-Roman-Alu 1 from Earth is currently 846,235,325 kilometers, equivalent to 5.656734 Astronomical Units. Light takes 47 minutes and 2.7372 seconds to travel from Comet 117P/Helin-Roman-Alu 1 and arrive to us.

47 minutes and 2.7372 seconds

The following chart shows the distance of Comet 117P/Helin-Roman-Alu 1 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 117P/Helin-Roman-Alu 1 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 117P/Helin-Roman-Alu 1 from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet 117P/Helin-Roman-Alu 1 to Earth

Between January 2013 and December 2100 the closest approach of Comet 117P/Helin-Roman-Alu 1 to Earth happens on Sun Jul 3 2022 at a distance of 2.03085199 Astronomical Units, or 303,811,134 kilometers:

Sun Jul 3 2022

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

Comet 117P/Helin-Roman-Alu 1 brightness

The current visual magnitude of Comet 117P/Helin-Roman-Alu 1 is 19.24.


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 behvior 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 117P/Helin-Roman-Alu 1, 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 117P/Helin-Roman-Alu 1 between January 2013 and December 2100

Comet 117P/Helin-Roman-Alu 1 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 117P/Helin-Roman-Alu 1 rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 69.7°
Max altitude: 58.8°
Azimuth: 290.3°
Comet 117P/Helin-Roman-Alu 1 is above the horizon from Greenwich, United Kingdom

The rise and set times are defined as the time at which the upper limb of Comet 117P/Helin-Roman-Alu 1 touches the horizon, consideting the effect of the atmospheric refraction. As the atmoshpere conditions cannot be modeled precisely the times reported here should be considered correct with an approximation of few minutes.

Comet 117P/Helin-Roman-Alu 1 Orbital Elements

The following table lists the orbital elements of Comet 117P/Helin-Roman-Alu 1 at epoch 30 June 2014 00:00 UTC (JD: 2456839.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.25388255
Orbit inclination i 8.69719020°
Perihelion distance q 3.05633124 AU
457,220,647 km
Aphelion distance Q 5.13629647 AU
768,379,017 km
Semi-major axis a 4.09631386 AU
612,799,832 km
Orbital period period 8.2900 years
3,028.2259 days
Date of perihelion transit Tp 2014-Mar-27 02:48:03
2,456,743.6167 JD
Next perihelion transit 2022-Jul-11 08:13
2,459,771.8426 JD
Argument of perihelion peri 222.67534523185°
Longitude of the ascending node node 58.895130958862°
Mean anomaly M 11.398748391825°
Mean motion n 0.11888149°/day

Visualization of Comet 117P/Helin-Roman-Alu 1 Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet 117P/Helin-Roman-Alu 1 with respect of the Sun and the orbits of the major planets. The position of Comet 117P/Helin-Roman-Alu 1 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 117P/Helin-Roman-Alu 1
View Comet 117P/Helin-Roman-Alu 1 in the 3D Solar System Simulator

Comet 117P/Helin-Roman-Alu 1 15 Days Ephemeris

The following table lists the ephemerides of Comet 117P/Helin-Roman-Alu 1 computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet 117P/Helin-Roman-Alu 1 in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2019 Sep 08 09h 49m 08s +20° 48’ 24” 19.27 Leo
2019 Sep 09 09h 50m 03s +20° 44’ 21” 19.27 Leo
2019 Sep 10 09h 50m 59s +20° 40’ 17” 19.26 Leo
2019 Sep 11 09h 51m 55s +20° 36’ 14” 19.26 Leo
2019 Sep 12 09h 52m 50s +20° 32’ 11” 19.26 Leo
2019 Sep 13 09h 53m 45s +20° 28’ 09” 19.25 Leo
2019 Sep 14 09h 54m 41s +20° 24’ 10” 19.25 Leo
2019 Sep 15 09h 55m 36s +20° 20’ 09” 19.24 Leo
2019 Sep 16 09h 56m 30s +20° 16’ 10” 19.24 Leo
2019 Sep 17 09h 57m 24s +20° 12’ 14” 19.23 Leo
2019 Sep 18 09h 58m 19s +20° 08’ 17” 19.23 Leo
2019 Sep 19 09h 59m 13s +20° 04’ 22” 19.22 Leo
2019 Sep 20 10h 00m 07s +20° 00’ 28” 19.22 Leo
2019 Sep 21 10h 01m 01s +19° 56’ 34” 19.21 Leo