emamajek on 08-Oct-2019 06:34:25 GMT about BD-17 6768
GJ 897 (HIP 116191) is a much nearer system than evidenced by the quoted Hipparcos parallax. GJ 897 is a tight resolved binary (0.7"; WDS) with V(A)=11.14, V(B)=11.17. Heintz (1986) calculates an orbit with period 28.2 year, a=0.59", e=0.15 and a dynamic parallax estimate of 59+-4 mas or 63 mas, when combining their data with that from other authors. Previous nearby star catalogs also list a parallax showing proximity to the Sun (69+-13 mas in Woolley+1970 catalog, 77.5+-9.0 mas in Gliese+1991 catalog, 64.8+-4.1 mas in CNS3 catalog). The nearly edge-on orbit (see https://ad.usno.navy.mil/wds/orb6/PNG/wds23328-1645a.png) led to poor Hipparcos astrometric solutions for GJ 897 (plx= -16.55+-13.75
mas, pmRA = 545.43+-21.94 mas/yr, pmDec = 326.62+-13.75 mas/yr; ESA 1997; plx = 5.16+-34.71 mas, pmRA = 566.21+-57.81 mas/yr, pmDec = 379.91+-55.55 mas/yr; van Leeuwen 2007). However, the GJ 897 binary
is a common proper motion system with the nearby star GJ 898 (see comments by Heintz 1986 for binary "V 28"; 1986A%26AS...65..411H). Tokovinin+2018 provide an updated dynamic parallax for GJ 897 of 66.00 mas (2018ApJS..235....6T).
I recommend replacing the default parallax (currently from the revised Hipparcos catalog) with either 64.8 +- 4.1 mas (CNS3) or 66.00 mas (2018ApJS..235....6T).
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