List of the brightest Kuiper belt objects explained

Since the year 2000, a number of Kuiper belt objects (KBOs) with diameters of between 500 and 1500 km (more than half that of Pluto) have been discovered. 50000 Quaoar, a classical KBO discovered in 2002, is over 1000 km across. and, both announced on 29 July 2005, are larger still. Other objects, such as 28978 Ixion (discovered in 2001) and 20000 Varuna (discovered in 2000) measure roughly 500 km across.^[1] This has led gradually to the acceptance of Pluto as the largest member of the Kuiper belt.

The brightest known dwarf planets and other KBOs (with absolute magnitudes < 4.0) are:

Number	Permanent Designation^[2]	Provisional Designation	Absolute magnitude	Bond Albedo (%)	Semimajor axis (AU)	Equatorial diameter (km)	Date found	Discoverer^[3]	Diameter method^[4]
134340			−0.8	72	39.4	2377	1930	C. Tombaugh	direct imaging
136472			−0.2	80	45.6	1430	2005	M. Brown, C. Trujillo, D. Rabinowitz	occultation
136108			0.2	51	43.3	1595	2003	Sierra Nevada Observatory (unofficial)	occultation
	Charon	S/1978 P 1	1.0	20 to 50 (geometric)	39.4	1212	1978	J. Christy	direct imaging
90482			2.2	23	39.3	910	2004	M. Brown, C. Trujillo, D. Rabinowitz	thermal
50000			2.4	11	43.7	1070	2002	C. Trujillo, M. Brown	thermal
174567			3.2	10	46.1	705	2003	J. A. Larsen	estimated
55565			3.3	11	47.2	768	2002	NEAT	thermal
55636			3.4	88	43.2	286	2002	NEAT	Haumea family, estimated
202421			3.5	20	43.2	498	2005	Palomar	estimated
307261			3.6	5	42.0	934	2002	C. Trujillo, M. Brown	thermal
208996			3.6	10	39.4	772	2003	C. Trujillo, M. Brown	thermal
20000			3.6	11	42.3	678	2000	Spacewatch	thermal
55637			3.6	11	42.5	665	2002	Spacewatch	thermal
28978			3.6	14	39.8	617	2001	DES	thermal
145452			3.7	11	41.6	679	2005	A. C. Becker, A. W. Puckett, J. Kubica	thermal
120178			3.9	70?	43.4	218?	2003	M. Brown, C. Trujillo, D. Rabinowitz	Haumea family, estimated

See also

• List of trans-Neptunian objects

Notes and References

1. Web site: The Solar System Beyond The Planets . Audrey Delsanti . David Jewitt . amp . Institute for Astronomy, University of Hawaii . 2007-03-09 . https://web.archive.org/web/20070129151907/http://www.ifa.hawaii.edu/faculty/jewitt/papers/2006/DJ06.pdf . 2007-01-29 . dead .
2. Web site: List of Known Trans-Neptunian Objects. Johnston, W. R.. 7 October 2018. 6 February 2019.
3. Web site: List of Transneptunian Objects. Minor Planet Center. 6 February 2019.
4. Web site: How many dwarf planets are there?. Brown, M.. 12 November 2018. 6 February 2019.