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🌎  Greenwich, United Kingdom [change]

Comet 117P/Helin-Roman-Alu 1

Comet 117P/Helin-Roman-Alu 1 is currently in the constellation of Libra. The current Right Ascension of Comet 117P/Helin-Roman-Alu 1 is 15h 48m 28s and the Declination is -19° 49’ 58” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet 117P/Helin-Roman-Alu 1 is 16.30 (JPL).

Summary of key facts about Comet 117P/Helin-Roman-Alu 1 [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]:

15h 48m 28s
-19° 49’ 58”

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 117P/Helin-Roman-Alu 1 available on TheSkyLive:

Available Resources

Comet 117P/Helin-Roman-Alu 1 Position and Finder Charts

Below we provide Comet 117P/Helin-Roman-Alu 1 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 117P/Helin-Roman-Alu 1 in Libra on November, 27 2021
Field of view: 50x30 degrees
View fullscreen
Map showing Comet 117P/Helin-Roman-Alu 1 in Libra on November, 27 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 117P/Helin-Roman-Alu 1 is right now. Click on the image to see a more detailed fullscreen tracker view.

117P/Helin-Roman-Alu 1
RA: 15h 48m 28s
Dec: -19° 49’ 58”
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 from Earth

The distance of Comet 117P/Helin-Roman-Alu 1 from Earth is currently 629,234,239 kilometers, equivalent to 4.206171 Astronomical Units. Light takes 34 minutes and 58.8995 seconds to travel from Comet 117P/Helin-Roman-Alu 1 and arrive to us.

34 minutes and 58.8995 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 2.030851 Astronomical Units, or 303,811,010 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 16.30.


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 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: 109.8°
Max altitude: 18.7°
Azimuth: 250.2°

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, 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 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
2021 Nov 20 15h 36m 26s -19° 00’ 28” 16.33 Libra
2021 Nov 21 15h 37m 59s -19° 06’ 56” 16.33 Libra
2021 Nov 22 15h 39m 29s -19° 13’ 21” 16.32 Libra
2021 Nov 23 15h 41m 02s -19° 19’ 42” 16.32 Libra
2021 Nov 24 15h 42m 33s -19° 26’ 03” 16.32 Libra
2021 Nov 25 15h 44m 05s -19° 32’ 20” 16.31 Libra
2021 Nov 26 15h 45m 38s -19° 38’ 35” 16.31 Libra
2021 Nov 27 15h 47m 11s -19° 44’ 45” 16.30 Libra
2021 Nov 28 15h 48m 42s -19° 50’ 54” 16.30 Libra
2021 Nov 29 15h 50m 16s -19° 57’ 02” 16.29 Libra
2021 Nov 30 15h 51m 48s -20° 03’ 05” 16.29 Libra
2021 Dec 01 15h 53m 21s -20° 09’ 06” 16.28 Libra
2021 Dec 02 15h 54m 55s -20° 15’ 03” 16.28 Libra
2021 Dec 03 15h 56m 29s -20° 20’ 57” 16.27 Libra