87P/Bus
{{short description|Periodic comet}}
{{Use dmy dates|date=June 2025}}
{{Infobox comet
| name = 87P/Bus
| image = Comet 87P Bus u65z1f02r.fits.gz sci.jpg
| caption = Comet 87P/Bus photographed by the Hubble Space Telescope on 7 June 2001
| discovery_ref = {{r|IAUC_3578}}
| discoverer = Schelte J. Bus
| discovery_site = UK Schmidt Telescope
| discovery_date = 2 March 1981
| mpc_name = P/1981 E1, P/1987 B4
| designations = {{unbulleted|1981 XI, 1987 XXXIV|1994 XVI|1981b, 1987f, 1993b}}
| orbit_ref = {{r|jpldata|MPC}}
| epoch = 31 May 2025 (JD 2459000.5)
| observation_arc = 39.57 years
| earliest_precovery_date = 9 February 1981
| obs = 801
| perihelion = 2.099 AU
| aphelion = 4.776 AU
| semimajor = 3.438 AU
| eccentricity = 0.38918
| period = 6.374 years
| inclination = 2.603°
| asc_node = 181.87°
| arg_peri = 24.932°
| mean = 3.356°
| tjup = 3.009
| Earth_moid = 1.098 AU
| Jupiter_moid = 0.181 AU
| physical_ref = {{r|Lamy_2009}}
| mean_radius = {{val|0.27|0.01}} km
| rotation = {{val|32.0|9.0}} hours
| M1 = 12.7
| M2 = 16.1
| magnitude =
| last_p = 9 May 2020
| next_p = 7 June 2029{{r|Horizons2029}}
}}
87P/Bus is a periodic comet with a current orbital period of 6.37 years around the Sun.
Observational history
It was discovered by Schelte J. Bus in 1981 on a plate taken with the 1.2m UK Schmidt telescope at Siding Spring, Australia. The discovery was announced in IAU Circular 3578 on March 4, 1981.{{r|IAUC_3578}} It has been observed on each of its subsequent apparitions, most recently in 2020.{{r|Yoshida}}
Physical characteristics
Its nucleus is estimated to have an effective radius of {{val|0.27|0.01}} km and to be elongated, with an a/b ratio greater than 2.2. Its rotational period is estimated to be {{val|32.0|9.0}} hours.{{r|Lamy_2009}}
Orbit
A close approach to Jupiter on 13 May 1952, at a distance of {{convert|0.0668|AU|e6km|abbr=unit}}, lowered the orbital period from 12.46 years and the perihelion distance from 4.43 AU to 6.43 years and 2.13 AU respectively. Another close approach to Jupiter on 24 February 2023, at a distance of {{convert|0.182|AU|e6km|abbr=unit}}, raised the perihelion to 3.62 AU and the orbital period to 9.58 years.{{r|Kinoshita}}
References
{{Reflist|refs=
| title= Horizons Batch for 87P/Bus (90000883) on 2029-Jun-07
| publisher= JPL Horizons
| type= Perihelion occurs when rdot flips from negative to positive
| url= https://ssd.jpl.nasa.gov/api/horizons.api?format=text&COMMAND=%27DES%3D87P%3BCAP%27&START_TIME=%272029-Jun-05%27&STOP_TIME=%272029-Jun-10%27&STEP_SIZE=%273%20hours%27&QUANTITIES=%2719%27
| access-date= 27 June 2022 }} (JPL#K203/18 Soln.date: 2020-Sep-28)
| author1= S. J. Bus
| author2= K. S. Russell
| editor1= D. W. Green
| title= Comet Bus (1981b)
| url= http://www.cbat.eps.harvard.edu/iauc/03500/03578.html
| journal= IAU Circular
| date= 1 March 1981
| volume= 3578
| issue= 1
| bibcode= 1981IAUC.3578....1B
| issn= 0081-0304 }}
| title= 87P/Bus – JPL Small-Body Database Lookup
| url= https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=87P
| website= ssd.jpl.nasa.gov
| publisher= Jet Propulsion Laboratory
| access-date= 20 March 2016 }}
| author1= K. Kinoshita
| title= 87P/Bus: Past, Present and Future orbital elements
| url= https://jcometobs.web.fc2.com/pcmtn/0087p.htm
| work= Comet Orbit
| date= 13 February 2014
| access-date= 13 November 2024 }}
| author1= P. L. Lamy
| author2= I. Toth
| author3= H. A. Weaver
| author4= M. F. A'Hearn
| author5= L. Jorda
| title= Properties of the nuclei and comae of 10 ecliptic comets from Hubble Space Telescope multi-orbit observations
| url= https://academic.oup.com/mnras/article-pdf/412/3/1573/3580898/mnras0412-1573.pdf
| journal= Monthly Notices of the Royal Astronomical Society
| year= 2011
| volume= 412
| issue= 3
| pages= 1573–1590
| doi= 10.1111/j.1365-2966.2010.17934.x
| doi-access= free }}
| title= 87P/Bus Orbit
| url= https://www.minorplanetcenter.net/db_search/show_object?object_id=87P
| publisher= Minor Planet Center
| access-date= 16 June 2014 }}
| author1= S. Yoshida
| title= 87P/Bus
| url= http://www.aerith.net/comet/catalog/0087P/index.html
| website= www.aerith.net
| access-date= 15 May 2015 }}
}}
External links
- {{JPL Small Body|id=1000010}}
- [http://www.aerith.net/comet/catalog/0087P/index.html 87P/Bus] at Seiichi Yoshida's website
{{PeriodicComets Navigator|86P/Wild|88P/Howell}}
{{Comets}}
{{Authority control}}
{{DEFAULTSORT:Bus, 087P}}