105P/Singer Brewster

{{Short description|Periodic comet with 6 year orbit}}

{{Use mdy dates|date=November 2012}}

{{Infobox comet

| name=105P/Singer Brewster

| image= 105P 2018-05-19 image ZTF-sso-473-zr-fov-2.8arcmin.png

| discoverer=Stephen Singer-Brewster

| discovery_date=May 3, 1986

| designations=1986 XI; 1992 XXVI

| epoch=2011-Feb-08
(JD 2455600.5)

| semimajor=3.4709 AU

| perihelion=2.0502 AU

| aphelion=4.8915 AU

| eccentricity=0.40929

| period=6.47 yr

| inclination=9.1706°

| last_p=2018-Aug-10
February 26, 2012
September 11, 2005
April 6, 1999

| next_p=2025-Jan-22{{mpc|105p}}

}}

105P/Singer Brewster is a periodic comet in the Solar System. It was discovered in 1986, and received the name of 1986d under the old naming system.

Because 105P/Singer Brewster only comes within 2 AU of the Sun, during the 2012 perihelion passage it is only expected to brighten to about apparent magnitude 17.

The comet nucleus is estimated to be 2.2 kilometers in diameter.

The orbit of Comet Singer Brewster was altered significantly in August 1976 when it passed within 0.376 AU of Jupiter and will be altered again in August 2059.

The single discoverer bears a hyphenated surname (Singer-Brewster), but co-discovered comets bear the names of the co-discoverers linked by hyphens, e.g. Shoemaker-Levy 9, Swift-Tuttle, etc. In these cases, the IAU either removes one of the parts of the name or replaces the hyphen by a space.{{citation|title=IAU Comet-naming Guidelines |publisher=International Astronomical Union |url=http://www.cbat.eps.harvard.edu/cometnameg.html |url-status=dead |archive-url=https://web.archive.org/web/20160304050435/https://www.cbat.eps.harvard.edu/cometnameg.html |archive-date=March 4, 2016 |df=mdy }}{{citation |journal= Journal of the Association of Lunar and Planetary Observers |title= Comet Corner |url=http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?journal=JALPO&year=%3f%3f%3f%3f&volume=..33&letter=.&db_key=GEN&page_ind=26&plate_select=NO&data_type=GIF&type=SCREEN_GIF&classic=YES |author= Don E. Machholz |author-link= Donald Machholz |volume= 33 |pages= 25–28, 26 |issue= 1 |date= 1989 |quote= A hyphen (-) is used in a comet's name only to separate the discoverers. Thus, when sometimes the discover has a double name, the hyphen is dropped from the comet's name in order to show that there was only one discoverer. For example, in 1986 Stephen Singer-Brewster discovered a comet. It is known as "Comet Singer Brewster." |bibcode = 1989JALPO..33...25M }}