Double Star Calculator - Orbit

Orbital Elements for OL18

WDS:	OL18	WDS ID/Discoverer
P:	319.400	Orbital period (years)
a:	1.746	Semi-major axis (arcseconds)
i:	86.6	Inclination (degrees)
Ω:	118.6	Longitude of ascending node (degrees)
T:	2045.220	Epoch of periastron passage (year)
e:	0.283	Eccentricity
ω:	190.0	Longitude of periastron (degrees)
Start-Year:	1865.3	Year
End-Year:	2184.7	Year
Epoch:	2026.5	Besselian Epoch

Further data from the WDS Sixth Catalog of Orbits for OL18
Position:	181905.58-350924.6	Epoch-2000 right ascension and declination
WDS-ID:	18191-3509	WDS designation
Discoverer Code:	OL18	Discover designation and components
ADS number:	.	Aitken Double Star catalog
HD number:	167981	HD catalog number
Hipparcos number:	89766	Hipparcos catalog number
V1:	9.17	Magnitude of the primary
V2:	9.73	Magnitude of the secondary
Equinox:	2000	Equinox
Date:	2021	Date of last observation
Orbit grade:	4	Orbit grade, ranging from : 1 = Definitive 2 = Good 3 = Reliable 4 = Preliminary 5 = Indeterminate
Flags:		Flags
Ephemerides:		Ephemerides
Code:	Tok2021c	Reference

Double Star Orbit for OL18

WDS 6th Orbit including measures of OL18

-- Image from the USNO WDS 6th Orbit Catalog (see Acknowledgements) --

Legend:

Green plus signs:	Visual (micrometric) measures
Violet asterisks:	Photographic measures
Blue symbols:	Various interferometric techniques
Dot-dash line:	Indicates the line of nodes

Ephemeris of OL18

Click to expand/collapse ephemeris:

Year       Sep[“]   PA[°]
---------------------------------------------
2026.50    1.159   296.79
--------------------------
1865.30    2.213   118.40
1866.30    2.216   118.44
1867.30    2.219   118.48
1868.30    2.222   118.52
1869.30    2.225   118.56
1870.30    2.227   118.60
1871.30    2.228   118.64
1872.30    2.229   118.68
1873.30    2.230   118.72
1874.30    2.230   118.76
1875.30    2.230   118.79
1876.30    2.230   118.83
1877.30    2.229   118.87
1878.30    2.228   118.91
1879.30    2.226   118.95
1880.30    2.224   118.99
1881.30    2.221   119.03
1882.30    2.218   119.07
1883.30    2.215   119.11
1884.30    2.211   119.15
1885.30    2.207   119.19
1886.30    2.203   119.23
1887.30    2.198   119.27
1888.30    2.192   119.31
1889.30    2.187   119.35
1890.30    2.180   119.39
1891.30    2.174   119.43
1892.30    2.167   119.48
1893.30    2.160   119.52
1894.30    2.152   119.56
1895.30    2.144   119.60
1896.30    2.135   119.64
1897.30    2.126   119.69
1898.30    2.117   119.73
1899.30    2.107   119.78
1900.30    2.097   119.82
1901.30    2.086   119.86
1902.30    2.076   119.91
1903.30    2.064   119.95
1904.30    2.053   120.00
1905.30    2.041   120.05
1906.30    2.028   120.09
1907.30    2.015   120.14
1908.30    2.002   120.19
1909.30    1.989   120.24
1910.30    1.975   120.29
1911.30    1.960   120.34
1912.30    1.946   120.39
1913.30    1.930   120.44
1914.30    1.915   120.50
1915.30    1.899   120.55
1916.30    1.883   120.60
1917.30    1.866   120.66
1918.30    1.849   120.72
1919.30    1.832   120.77
1920.30    1.814   120.83
1921.30    1.796   120.89
1922.30    1.778   120.95
1923.30    1.759   121.02
1924.30    1.740   121.08
1925.30    1.721   121.15
1926.30    1.701   121.21
1927.30    1.681   121.28
1928.30    1.660   121.35
1929.30    1.639   121.42
1930.30    1.618   121.50
1931.30    1.596   121.57
1932.30    1.575   121.65
1933.30    1.552   121.73
1934.30    1.530   121.81
1935.30    1.507   121.90
1936.30    1.483   121.98
1937.30    1.460   122.08
1938.30    1.436   122.17
1939.30    1.412   122.26
1940.30    1.387   122.36
1941.30    1.362   122.47
1942.30    1.337   122.58
1943.30    1.311   122.69
1944.30    1.286   122.80
1945.30    1.260   122.92
1946.30    1.233   123.05
1947.30    1.206   123.18
1948.30    1.179   123.32
1949.30    1.152   123.46
1950.30    1.124   123.61
1951.30    1.096   123.77
1952.30    1.068   123.94
1953.30    1.040   124.11
1954.30    1.011   124.30
1955.30    0.982   124.50
1956.30    0.953   124.71
1957.30    0.924   124.93
1958.30    0.894   125.16
1959.30    0.864   125.42
1960.30    0.834   125.69
1961.30    0.803   125.98
1962.30    0.773   126.30
1963.30    0.742   126.64
1964.30    0.711   127.01
1965.30    0.680   127.41
1966.30    0.648   127.86
1967.30    0.617   128.34
1968.30    0.585   128.89
1969.30    0.553   129.49
1970.30    0.521   130.17
1971.30    0.489   130.93
1972.30    0.457   131.81
1973.30    0.425   132.81
1974.30    0.393   133.98
1975.30    0.361   135.36
1976.30    0.329   137.01
1977.30    0.297   139.00
1978.30    0.266   141.48
1979.30    0.235   144.61
1980.30    0.205   148.67
1981.30    0.176   154.08
1982.30    0.150   161.52
1983.30    0.126   171.91
1984.30    0.109   186.22
1985.30    0.101   204.34
1986.30    0.103   223.52
1987.30    0.116   240.06
1988.30    0.136   252.49
1989.30    0.161   261.39
1990.30    0.189   267.80
1991.30    0.219   272.54
1992.30    0.249   276.13
1993.30    0.280   278.93
1994.30    0.311   281.18
1995.30    0.343   283.00
1996.30    0.375   284.52
1997.30    0.407   285.80
1998.30    0.439   286.90
1999.30    0.470   287.85
2000.30    0.502   288.67
2001.30    0.533   289.41
2002.30    0.564   290.05
2003.30    0.595   290.64
2004.30    0.626   291.16
2005.30    0.656   291.64
2006.30    0.686   292.07
2007.30    0.715   292.47
2008.30    0.744   292.84
2009.30    0.773   293.18
2010.30    0.801   293.49
2011.30    0.828   293.79
2012.30    0.855   294.06
2013.30    0.882   294.32
2014.30    0.908   294.57
2015.30    0.933   294.80
2016.30    0.957   295.02
2017.30    0.981   295.22
2018.30    1.004   295.42
2019.30    1.026   295.61
2020.30    1.047   295.79
2021.30    1.068   295.97
2022.30    1.087   296.14
2023.30    1.106   296.30
2024.30    1.124   296.46
2025.30    1.141   296.61
2026.30    1.156   296.76
2027.30    1.171   296.90
2028.30    1.185   297.04
2029.30    1.197   297.18
2030.30    1.209   297.32
2031.30    1.219   297.45
2032.30    1.228   297.58
2033.30    1.236   297.71
2034.30    1.243   297.83
2035.30    1.248   297.96
2036.30    1.252   298.09
2037.30    1.255   298.21
2038.30    1.257   298.33
2039.30    1.257   298.46
2040.30    1.256   298.58
2041.30    1.254   298.70
2042.30    1.251   298.83
2043.30    1.246   298.95
2044.30    1.240   299.08
2045.30    1.232   299.21
2046.30    1.224   299.34
2047.30    1.214   299.47
2048.30    1.202   299.60
2049.30    1.190   299.74
2050.30    1.176   299.88
2051.30    1.161   300.02
2052.30    1.145   300.17
2053.30    1.128   300.32
2054.30    1.109   300.48
2055.30    1.090   300.64
2056.30    1.069   300.81
2057.30    1.048   300.98
2058.30    1.025   301.16
2059.30    1.001   301.35
2060.30    0.976   301.55
2061.30    0.951   301.76
2062.30    0.924   301.99
2063.30    0.897   302.22
2064.30    0.869   302.47
2065.30    0.840   302.74
2066.30    0.811   303.03
2067.30    0.780   303.34
2068.30    0.749   303.67
2069.30    0.718   304.03
2070.30    0.686   304.43
2071.30    0.653   304.87
2072.30    0.620   305.35
2073.30    0.586   305.89
2074.30    0.552   306.49
2075.30    0.518   307.18
2076.30    0.483   307.96
2077.30    0.448   308.86
2078.30    0.413   309.91
2079.30    0.378   311.16
2080.30    0.343   312.67
2081.30    0.308   314.52
2082.30    0.273   316.85
2083.30    0.238   319.87
2084.30    0.204   323.89
2085.30    0.172   329.47
2086.30    0.141   337.56
2087.30    0.115   349.67
2088.30    0.097     7.51
2089.30    0.091    30.35
2090.30    0.100    52.41
2091.30    0.120    68.88
2092.30    0.148    79.92
2093.30    0.179    87.34
2094.30    0.212    92.51
2095.30    0.246    96.26
2096.30    0.281    99.09
2097.30    0.316   101.30
2098.30    0.351   103.06
2099.30    0.387   104.50
2100.30    0.422   105.70
2101.30    0.458   106.71
2102.30    0.493   107.57
2103.30    0.529   108.32
2104.30    0.564   108.98
2105.30    0.599   109.56
2106.30    0.633   110.07
2107.30    0.668   110.53
2108.30    0.702   110.95
2109.30    0.736   111.33
2110.30    0.770   111.67
2111.30    0.804   111.99
2112.30    0.837   112.28
2113.30    0.870   112.55
2114.30    0.902   112.80
2115.30    0.935   113.03
2116.30    0.967   113.25
2117.30    0.998   113.45
2118.30    1.030   113.64
2119.30    1.061   113.82
2120.30    1.091   113.99
2121.30    1.122   114.15
2122.30    1.151   114.30
2123.30    1.181   114.44
2124.30    1.210   114.58
2125.30    1.239   114.71
2126.30    1.267   114.83
2127.30    1.296   114.95
2128.30    1.323   115.07
2129.30    1.350   115.18
2130.30    1.377   115.28
2131.30    1.404   115.38
2132.30    1.430   115.48
2133.30    1.456   115.57
2134.30    1.481   115.66
2135.30    1.506   115.75
2136.30    1.530   115.84
2137.30    1.554   115.92
2138.30    1.578   116.00
2139.30    1.601   116.08
2140.30    1.624   116.15
2141.30    1.647   116.22
2142.30    1.669   116.29
2143.30    1.690   116.36
2144.30    1.711   116.43
2145.30    1.732   116.50
2146.30    1.753   116.56
2147.30    1.773   116.62
2148.30    1.792   116.69
2149.30    1.811   116.75
2150.30    1.830   116.81
2151.30    1.848   116.86
2152.30    1.866   116.92
2153.30    1.883   116.98
2154.30    1.900   117.03
2155.30    1.917   117.08
2156.30    1.933   117.14
2157.30    1.948   117.19
2158.30    1.964   117.24
2159.30    1.978   117.29
2160.30    1.993   117.34
2161.30    2.007   117.39
2162.30    2.020   117.44
2163.30    2.033   117.48
2164.30    2.046   117.53
2165.30    2.058   117.58
2166.30    2.070   117.62
2167.30    2.082   117.67
2168.30    2.093   117.71
2169.30    2.103   117.76
2170.30    2.113   117.80
2171.30    2.123   117.85
2172.30    2.132   117.89
2173.30    2.141   117.93
2174.30    2.150   117.97
2175.30    2.158   118.02
2176.30    2.165   118.06
2177.30    2.173   118.10
2178.30    2.179   118.14
2179.30    2.186   118.18
2180.30    2.192   118.22
2181.30    2.197   118.26
2182.30    2.202   118.30
2183.30    2.207   118.34
2184.30    2.211   118.38

Disclaimer

This result is provided without warranty. For all terms, see the Full Disclaimer. Copyright (C) 2025. Unless otherwise noted, all output generated by the Double Star Calculator including orbit diagrams, ephemerides, and analytical reports is licensed under CC BY 4.0.

Acknowledgements

The Double Star Calculator - Orbital Elements makes use of the Washington Double Star Sixth Catalog of Orbits of Visual Binary Stars, maintained at the U.S. Naval Observatory.

Report Information

Double Star Calculator:		Version 1.2 ($Rev: 2397 $)
Report created:		2026-06-25 17:50:27