During 2015–2017, three additional photometric observation were made at the Californian Center for Solar System Studies by Robert Stephens, Daniel Coley and Brian Warner in collaboration with Linda French from Illinois Wesleyan University. The two best-rated lightcurves gave a period of 17.383 and 17.44 with an amplitude of 0.08 and 0.11 magnitude, respectively, indicating that the body has a nearly spherical shape (U=3-/3-).[11][12][a]
Diameter and albedo
According to the surveys carried out by the Japanese Akari satellite, the Infrared Astronomical Satellite IRAS, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Iphinous measures between 64.71 and 68.98 kilometers in diameter and its surface has an albedo between 0.045 and 0.067.[7][8][9]
The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0510 and a diameter of 64.51 kilometers based on an absolute magnitude of 9.8.[4]
100+ largest Jupiter trojans
Largest Jupiter Trojans by survey(A) (mean-diameter in kilometers; YoD: Year of Discovery)
Note: missing data was completed with figures from the JPL SBDB (query) and from the LCDB (query form) for the WISE/NEOWISE and SIMPS catalogs, respectively. These figures are given in italics. Also, listing is incomplete above #100.
Notes
^ abcdThree lightcurve plots of (11395) Iphinous by Robert Stephens and collaborators at the Center for Solar System Studies (U81) in Landers, California. Plots from 2015 (poor), 2016 and 2017. Summary figures at the LCDB.
^ abcdTedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System – IRAS-A-FPA-3-RDR-IMPS-V6.0. 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 15 June 2018.
^ abcdUsui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
^ abcStephens, Robert D.; Coley, Daniel R.; Warner, Brian D.; French, Linda, M. (October 2016). "Lightcurves of Jovian Trojan Asteroids from the Center for Solar System Studies: L4 Greek Camp and Spies". The Minor Planet Bulletin. 43 (4): 323–331. Bibcode:2016MPBu...43..323S. ISSN1052-8091.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^ abStephens, Robert D.; Warner, Brian D. (October 2017). "Lightcurve Analysis of L4 Trojan Asteroids at the Center for Solar System Studies 2017 April–June". The Minor Planet Bulletin. 44 (4): 312–316. Bibcode:2017MPBu...44..312S. ISSN1052-8091.