309 Fraternitas

{{Infobox planet

| minorplanet=yes

| background=#D6D6D6

| name=309 Fraternitas

| discoverer=Johann Palisa

|image= Орбита астероида 309.png

|caption=Orbital diagram

| discovered=6 April 1891

| mpc_name=(309) Fraternitas

| alt_names=

| pronounced= {{IPAc-en|f|r|ə|'|t|ɜːr|n|ᵻ|t|æ|s}}

| named_after=fraternity

| mp_category=Main belt

| epoch=31 July 2016 (JD 2457600.5)

| semimajor={{cvt|2.66453|AU|Gm}}

| perihelion={{cvt|2.35779|AU|Gm}}

| aphelion={{cvt|2.97127|AU|Gm|lk=on}}

| eccentricity=0.11512

| period={{cvt|1588.7|days|years|2|order=flip}} 4.35 yr (1588.7 d)

| inclination=3.71999°

| asc_node=356.574°

| arg_peri=310.477°

| mean_anomaly=190.308°

| dimensions={{val|45.32|3.3|ul=km}}

| mass=

| density=

| rotation={{Convert|22.398|h|d|abbr=on|lk=on}}

| spectral_type=

| abs_magnitude=10.7

| albedo={{val|0.0595|0.010}}

| mean_motion={{Deg2DMS|0.226607|sup=ms}} / day

| orbit_ref={{Cite web |url=https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=309;cad=1 |archive-url=https://web.archive.org/web/20200915030722/https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=309;cad=1 |url-status=dead |archive-date=15 September 2020 |title=309 Fraternitas |work=JPL Small-Body Database |publisher=NASA/Jet Propulsion Laboratory |access-date=11 May 2016}}

| observation_arc=125.03 yr (45667 d)

| uncertainty=0

}}

309 Fraternitas is a typical Main belt asteroid.{{cite web|url=http://www.kentauren.info/menu/index1.htm?page=/cgi-bin/astorb2txt.pl%3FSuchname%3DFraternitas|title=Osculating elements from astorb-database for 309 Fraternitas|publisher=The Centaur Research Project|access-date=5 April 2015}} It was discovered by Johann Palisa on 6 April 1891 in Vienna. The asteroid name is Latin for 'fraternity'; it was so named in order to commemorate the 25th anniversary of the Maturitätsprüfung Fraternity.

This minor planet is orbiting the Sun at a distance of {{val|2.665|ul=AU}} with an orbital eccentricity (ovalness) of 0.115 and a period of {{cvt|1588.7|days|years|2|disp=out}}. The orbital plane is inclined at an angle of 3.72° of the ecliptic. Analysis of the asymmetric bimodal light curve of the asteroid from photometric data collected during 2014 provide a rotation period of {{val|22.398|0.001|u=hours}} with a brightness variation of {{val|0.12|0.01}} in magnitude.