C/2023 P1 (Nishimura)
{{Short description|Long-period comet}}
{{For|the other comet of the same name|C/2021 O1 (Nishimura)}}
{{Infobox comet
| name = C/2023 P1 (Nishimura)
| image = 6min-RGB-C2023 P1 (Nishimura).png
| caption = Comet Nishimura photographed from Trevinca, Spain on 25 August 2023
| discovery_ref = {{r|CBET_5285}}
| discoverer = Hideo Nishimura
| discovery_site = Kakegawa, Japan
| discovery_date = 12 August 2023
| mpc_name = C/2023 P1
| designations = HN00003
| orbit_ref = {{r|barycenter|jpldata}}
| epoch = 8 September 2023 (JD 2460195.5)
| observation_arc = 495 days (1.36 years)
| earliest_precovery_date = 19 January 2023
| obs = 638
| semimajor = 57.77 AU
| aphelion = 115.32 AU (1800)
110 AU (2200)
| perihelion = 0.225 AU
| eccentricity = {{Val|0.9961}} (1800)
{{val|0.9959}} (2200)
| period = ≈431 years (inbound)
≈406 years (outbound)
| max_speed = 88.7 km/s{{r|Perihelion}}
| inclination = 132.48°
| asc_node = 66.834°
| arg_peri = 116.30°
| tjup = –0.307
| Earth_moid = 0.079 AU
| Jupiter_moid = 2.328 AU
| physical_ref = {{r|jpldata}}
| M1 = 12.2
| M2 =
| magnitude = 2.5
{{small|(2023 apparition)}}
| last_p = 17 September 2023{{r|Perihelion|jpldata}}
≈1588–1592{{r|CBET_5291|barycenter}}
| next_p = ≈2430 Feb{{r|Perihelion2430}}
}}
C/2023 P1 (Nishimura) is a long-period comet discovered by Hideo Nishimura on 12 August 2023.{{r|NYT-20230908}} The comet passed perihelion on 17 September 2023 and reached an apparent magnitude of about 2.5.{{r|Yoshida_20231209}}
Observational history
Japanese amateur astronomer Hideo Nishimura discovered the comet in images he obtained using a 200-mm f/3 telephoto lens mounted on a Canon EOS 6D on 12 August 2023, when the comet was 1.0 AU from the Sun. He also found it in images he exposed the previous night.{{r|CBET_5285}} The comet upon discovery was located in the dawn sky and moving closer to the Sun and has been less than 50 degrees from the Sun since April 2023. Its apparent magnitude was estimated to be around 10–11.{{r|CBET_5285}} Pre-discovery images from 19, 24, and 25 January 2023 from PanSTARRS were identified by Robert Weryk extending the observation arc to seven months. The comet appeared in them as a stellar object with an apparent magnitude of about 22.{{r|CBET_5291}}
The comet brightened rapidly and by 27 August its apparent magnitude was estimated to be 7.3 and its coma to have a diameter of 5 arcminutes, while a thin ion tail 1.5–2 degrees long is visible in photographs.{{r|CBET_5290}} The comet was spotted with the naked eye by Piotr Guzik on 8 September at an estimated magnitude of 4.7.{{r|cobs_2023p1}} The comet tail was up to 7.5 degrees long when imaged with CCD.{{r|cobs_2023p1}} On 12 September 2023 the comet passed {{Convert|0.84|AU|e6km e6mi LD|abbr=unit}} from Earth but was only 15 degrees from the glare of the Sun.{{r|Earth20230912}}
On 17 September 2023 the comet came to perihelion 0.22 AU from the Sun.{{r|Perihelion|jpldata}} The comet appeared briefly in the evening sky in mid September, being 5 degrees over the horizon 30 minutes after sunset at 35° north latitude.{{r|Dickinson_2023}} Even though the comet reached a naked eye apparent magnitude of around +2, it was difficult to locate against the glare of the Sun.{{r|Todd_2023|Yoshida}} After perihelion, the comet became visible in the coronograph of STEREO, without showing signs of disintegration.{{r|Space.com1}} The comet was also observed by Parker Solar Probe on 27-28 September 2023, during encounter 17.{{r|Parker-17}}
Orbital characteristics
With an observation arc of seven months, the outbound orbital period of the comet is estimated to be about 406 years.{{r|barycenter}} An eccentricity of 0.996 gives the comet a semi-major axis of about 57 AU,{{r|jpldata}} which is comparable to the average distance of Eris at 68 AU. The comet will not leave the Solar System, will come to aphelion (farthest distance from the Sun) in 2227,{{r|Aphelion2227}} and return around the year 2430.{{r|Perihelion2430}}
| class=wikitable style="text-align:center; font-size:11px; float:right; margin:2px" |
| bgcolor= style="font-size: smaller;"
| colspan="8" style="text-align:center;"|Perihelion |
| 302 |
| 723 |
| 1169 |
| 1588–1592{{r|barycenter}} |
| 2023-09-17 |
| 2430 Feb{{r|Perihelion2430}} |
| class="wikitable" style="text-align: center; font-size: 0.9em;"
|+C/2023 P1 closest Earth approach on 12 September ! Date and time of ! Earth distance ! Sun distance ! Velocity ! Velocity ! Uncertainty | ||||||
| 12 September 2023 ≈09:20 | {{Convert|0.838|AU|e6km e6mi LD|abbr=unit|lk=on}} | {{Convert|0.292|AU|e6km e6mi LD|abbr=unit}} | 107.0 | 77.9 | ± 300 km | 14.9° |
Meteor shower
It is possible that Comet C/2023 P1 (Nishimura) may be related to the Sigma Hydrids meteor shower that is active November 22 to January 18 (peaking around November 30).{{r|CBET_5290}} The comet and the meteors have very similar orbit, with the meteor's perihelion having a very small offset from the comet. If C/2023 P1 isn't the parent body then it is a comet closely related to it.{{r|Greaves_2023}}
Gallery
Comet C 2023 P1 (Nishimura) 2023.08.30 05.47.00 UTC.png|The comet on 30 August, from an online telescope
Comet C2023 P1 Nishimura on 6 September 2023.jpg|The comet on 6 September, with a telephoto lens
Comet C2023 P1 Nishimura before dawn.jpg|The comet in the dawn sky on 9 September
Cometnishimura.png|Comet Nishimura as seen from STEREO on 22 September
{{clear}}
References
{{Reflist|refs=
|title=Electronic Telegram No. 5285
|publisher=Central Bureau for Astronomical Telegrams
|date=2023-08-15
|url=http://www.cbat.eps.harvard.edu/iau/cbet/005200/CBET005285.txt
|accessdate=2023-08-20}}
|title=CBET 5290 : COMET C/2023 P1 (NISHIMURA)
|publisher=Central Bureau for Astronomical Telegrams
|date=2023-08-29
|url=http://www.cbat.eps.harvard.edu/iau/cbet/005200/CBET005290.txt
|accessdate=2023-08-29}}
|title=CBET 5291 : COMET C/2023 P1 (NISHIMURA)
|publisher=Central Bureau for Astronomical Telegrams
|date=2023-08-29
|url=http://www.cbat.eps.harvard.edu/iau/cbet/005200/CBET005291.txt
|accessdate=2023-08-30}}
| title= Comet C/2023 P1 (Nishimura) observation list
| url= https://cobs.si/obs/comet/2447/
| website= cobs.si
| publisher= COBS - Comet OBServation database
| access-date= 10 September 2023 }} (2023-09-08 02:23 and 2023-09-07 02:23 Piotr Guzik. Inst T = E is naked eye)
| author1= D. Dickinson
| title= Comet P1 Nishimura Could Be Bright Over the Next Few Weeks
| url= https://www.universetoday.com/162802/comet-p1-nishimura-could-be-bright-over-the-next-few-weeks/
| website= Universe Today
| date= 18 August 2023
| access-date= 22 August 2023 }}
| author1= J. Greaves
| title= The remarkable similarity of the orbit of C/2023 P1 Nishimura and the σ Hydrid meteor shower
| url= https://articles.adsabs.harvard.edu/pdf/2023eMetN...8..281G
| journal= eMeteorNews
| year= 2023
| volume= 8
| issue= 5
| pages= 281–282
| bibcode= 2023eMetN...8..281G
| issn= 3041-4261 }}
| title= C/2023 P1 (Nishimura) – JPL Small-Body Database Lookup
| url= https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=2023P1
| website= ssd.jpl.nasa.gov
| publisher= Jet Propulsion Laboratory
| access-date= 13 September 2023 }}
| author1= K. Miller
| title= Don't Miss Comet Nishimura This Weekend, a Once-in-a-Lifetime View
| url= https://www.nytimes.com/2023/09/08/science/comet-nishimura.html
| newspaper= The New York Times
| date= 8 September 2023
| access-date= 9 September 2023
| archive-date= 9 September 2023
| archive-url= https://archive.today/20230909015534/https://www.nytimes.com/2023/09/08/science/comet-nishimura.html
| url-access= subscription
| url-status= live }}
| title= Encounter 17 Summary
| url= https://wispr.nrl.navy.mil/encounter17-summary
| website= wispr.nrl.navy.mil
| publisher= US Naval Research Laboratory
| access-date= 27 March 2024 }}
| author1= R. Lea
| title= Comet Nishimura photobombs NASA spacecraft after its close encounter with the sun (photos)
| url= https://www.space.com/comet-nishimura-photobombs-sun-spacecraft
| website= Space.com
| date= 20 September 2023
| access-date= 22 September 2023 }}
| author1= I. Todd
| title= Farewell Nishimura! Comet P1 moves into the southern hemisphere sky
| url= https://www.skyatnightmagazine.com/news/comet-p1-nishimura-southern-hemisphere
| magazine= Sky at Night Magazine
| publisher= BBC
| date= 22 September 2023
| access-date= 23 September 2023 }}
| author1= S. Yoshida
| title= C/2023 P1 (Nishimura)
| url= http://www.aerith.net/comet/catalog/2023P1/2023P1.html
| website= www.aerith.net
| access-date= 20 August 2023 }}
| author1= S. Yoshida
| title= Weekly Information about Bright Comets (2023 Dec. 9: North)
| url= http://www.aerith.net/comet/weekly/20231209n.html
| website= www.aerith.net
| access-date= 23 December 2023 }}
|title=Horizons Batch for C/2023 P1 (Nishimura) on 2023-Sep-12
|publisher=JPL Horizons
|type=closest Earth approach occurs when deldot flips from negative to positive
|url=https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272023+P1%27&START_TIME=%272023-Sep-12%2008:30%27&STOP_TIME=%272023-Sep-12%2010:00%27&STEP_SIZE=%27180%27&QUANTITIES=%2719,20,22,23,39%27
|archive-url=https://web.archive.org/web/20230820212840/https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272023+P1%27&START_TIME=%272023-Sep-12%27&STOP_TIME=%272023-Sep-13%27&STEP_SIZE=%271%20hour%27&QUANTITIES=%2719,20,22,23%27
|archive-date=2023-08-20
|url-status=live
|accessdate=2023-09-13}}
|title=Horizons Batch for C/2023 P1 (Nishimura) on 2023-Sep-17
|publisher=JPL Horizons
|type=Perihelion occurs when rdot flips from negative to positive
|url=https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272023+P1%27&START_TIME=%272023-Sep-17%2015:00%27&STOP_TIME=%272023-Sep-17%2016:00%27&STEP_SIZE=%27120%27&QUANTITIES=%2719,22%27&CENTER=%27@Sun%27
|archive-url=https://web.archive.org/web/20230822112015/https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272023+P1%27&START_TIME=%272023-Sep-17%27&STOP_TIME=%272023-Sep-18%27&STEP_SIZE=%27120%27&QUANTITIES=%2719,22%27&CENTER=%27@Sun%27
|archive-date=2023-08-22
|url-status=live
|accessdate=2023-09-07}}
|title=Horizons Batch for C/2023 P1 (Nishimura) in 2227
|publisher=JPL Horizons
|type=Aphelion occurs when rdot flips from positive to negative
|url=https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272023+P1%27&START_TIME=%272227-Jan-01%27&STOP_TIME=%272227-Aug-01%27&STEP_SIZE=%2760%27&QUANTITIES=%2719,22%27&CENTER=%27@Sun%27
|accessdate=2023-09-09}}
|title=Horizons Batch for C/2023 P1 (Nishimura) on 2430-Feb-04
|publisher=JPL Horizons
|type=Perihelion occurs when rdot flips from negative to positive
|url=https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272023+P1%27&START_TIME=%272430-Jan-01%27&STOP_TIME=%272430-Jun-01%27&STEP_SIZE=%27120%27&QUANTITIES=%2719,22%27&CENTER=%27@Sun%27
|archive-url=https://web.archive.org/web/20230901170017/https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272023+P1%27&START_TIME=%272431-Mar-01%27&STOP_TIME=%272431-Mar-20%27&STEP_SIZE=%27120%27&QUANTITIES=%2719,22%27&CENTER=%27@Sun%27
|archive-date=2023-09-01
|url-status=live
|accessdate=2023-09-13}}
|title=Barycentric Osculating Orbital Elements for Comet C/2023 P1 (Nishimura)
|author=Horizons output
|url=https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%272023+P1%27&TABLE_TYPE=%27ELEMENTS%27&START_TIME=%271800-01-01%27&STOP_TIME=%272200-01-01%27&STEP_SIZE=%27400%20years%27&CENTER=%27@0%27&OUT_UNITS=%27AU-D%27
|accessdate=2023-09-13
}} (Solution using the Solar System's barycenter (Sun+Jupiter). Select Ephemeris Type:Elements and Center:@0)
Epoch 1800: PR= 1.577E+05 / 365.25 = 431 years (inbound)
Epoch 2200: PR= 1.484E+05 / 365.25 = 406 years (outbound)
Epoch 1800 Tp of Julian day 2302476.6 converts to [https://ssd.jpl.nasa.gov/tools/jdc/#/jd 1591.]
}}
External links
{{Commons category}}
- {{JPL Small Body|id=1003941}}
{{Comets}}
{{2023 in space}}
{{Authority control}}
{{DEFAULTSORT:Nishimura, 2023 P1}}