33P/Daniel

{{Short description|Periodic comet with 8 year orbit}}

{{Infobox comet

| name=33P/Daniel

| image= D629 1909-12-15 33PDaniel.jpg

| caption= The comet on 15 December 1909 by Heidelberg Observatory

| discoverer=Zaccheus Daniel

| discovery_date={{nobr|December 7, 1909}}

| designations=P/1909 X1,
P/1937 B1

| epoch=June 25, 2000

| Jupiter_moid = {{Convert|0.152|AU|km|abbr=on}}

| aphelion=5.89 AU

| perihelion=2.157 AU

| semimajor=4.021 AU

| eccentricity=0.4635

| period=8.065 a

| inclination=22.41°

| dimensions=2.6 km

| last_p=November 11, 2024 August 22,{{mpc|33p}} 2016

| next_p = February 19, 2033

}}

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 distance at different epochs
Epoch	Perihelion (AU)
1903	1.38
1916	1.53
1964	1.66
2000	2.16
2041	2.25

Comet Daniel is a periodic comet in the Solar System discovered by Zaccheus Daniel (Halsted Observatory, Princeton University, New Jersey, United States) on December 7, 1909, estimated as magnitude 9.

Following its discovery, the returns for 1916, 1923, and 1930 were predicted but on each occasion, it was not recovered.

The 1937 return was recovered by Shin-ichi Shimizu (Simada, Japan) on January 31 after a calculation of the comet's orbit by Hidewo Hirose (Tokyo, Japan) after he took calculations for the 1923 return done by Alexander D. Dubiago and took into account perturbations from Jupiter.

Since then, all returns apart from 1957 and 1971 have been recovered.

Since its first discovery, this comet's orbital period has steadily increased due to repeated close encounters with Jupiter.

The comet nucleus is estimated to be 2.6 kilometers in diameter.

At some point between 2009 January 11 and 30 the comet underwent an outburst of around 3 magnitudes, brightening from 18th to 15th magnitude.{{cite web

|date=2011-12-18

|title=BAA Comet Section : Periodic Comets

|url=http://www.ast.cam.ac.uk/~jds/per01.htm#33P

|publisher=Jonathan Shanklin

|access-date=2012-10-26}}