User:ShellfaceTheStrange/sandbox

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Sigma Coronae Borealis (quintuple; RS CVn var FG binary with millenia-orbit G comp, and wide M astrometric binary)

Gliese 586 (quadruple; extremely eccentric (e=~0.98) G/K-dwarf & K/M-dwarf binary in CPM with K-dwarf and wider M-dwarf. Secondary K-dwarf is active (and not a close binary), but primary is not active, prob. due to interaction between Aab causing loss of momentum)

Epsilon Cygni (quadruple; see below)

Xi Ursae Majoris (Quintuple, 1-2 BDs; intermediate solar-type visual binary where both components are SB1s, with wide CPM Brown Dwarf.)

94 Ceti (Triple?; intermediate F-M binary, primary pl host; secondary definite binary, but little known params)

Chi Tauri (quintuple or sextuple; B9.5 dwarf in CPM with F-G ~17d SB2, with SB1 massive 10yr orbit; this comp is close mid K binary. primary is erratic variable, possible binary but little RV var)

Zeta Herculis (double; nearby 34-year 1" visual-spectroscopic binary consisting of early G-subgiant and end G-start K dwarf. Primary is well studied by astroseismology, but secondary not well known. Radial velocity data extends beyond a century; would be interesting to compile them like Alpha Centauri. Almost always single-lined, though the secondary has been observed a few times and some ELODIE observations retrieve a small second peak offset by a few km/s. Will evolve into a Procyon-system in a few hundred myr, into something like Gliese 86.)

Chi1 Orionis (double; very young G0V star in 14-year binary with late M-dwarf; unusually high mass ratio. Evaporated member of the Ursa Major moving group, apparently with tentative association to the G5V+D binary HD 147513 (though I can't remember where I got that from))

94 Aquarii (triple; subgiant late G star in 5yr KM binary, with CPM early K. Söderhjelm (1999) provides lower total system parallax (40.28 ± 1.51 mas = 80.97 ± 3.04 ly), which has better agreement with the apparent magnitudes of A and B.)

Psi1 Draconis (Psi Draconis) (triple; see below. Boyajian et al. 2011 support the close binarity of A)

AR Cassiopeiae (septuple)

171 Puppis (HD 63077) (triple; evolved sd binary with wide CPM DC wd)

HD 20782/20781 (HD 20782) (double; early-mid G dwarf in ~10000 AU CPM with start-K dwarf. Both pl hosts)

Theta Gruis (triple; evolved F star in astro-visual binary, with wide CPM FG dwarf)

Gliese 60 (quadruple; 6yr K binary where secondary is EB, with ~100 AU M dwarf)

Pi Cephei (Triple, possibly quadruple. CPM with Rho Cep?)

HD 24496 (double; start G dwarf in intermediate binary with KM star. Primary retracted pl host.)

HD 132563 (triple; F-G CPM with primary long period SB1. Secondary pl host.)

Iota Crateris (double; mid-late F dwarf with intermediate K comp. Primary RV var, trend due to comp.)

Kepler-90 (KOI-351; 7 planets)

Kepler-89 (KOI-94; potentially double, 4 planets)

Kepler-78 (1 really freakin' hot planet)

Kepler-68 (3 planets)

Sigma Coronae Borealis

Sigma Coronae Borealis AabBCab

Sigma Coronae Borealis. The C component is circled. Credit: POSS-II
A star chart of the constellation of Corona Borealis circling the position of σ.
Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Corona Borealis
Sigma Coronae Borealis Aab
Right ascension	16h 14m 40.86s
Declination	+33° 51′ 30.95″
Apparent magnitude (V)	5.560 ± 0.009
Sigma Coronae Borealis B
Right ascension	16h 14m 40.39s
Declination	+33° 51′ 27.05″
Apparent magnitude (V)	6.428 ± 0.010
Sigma Coronae Borealis Cab
Right ascension	16h 13m 56.27s
Declination	+33 46 24.30°
Apparent magnitude (V)	12.34 ± 0.09
Characteristics
Sigma Coronae Borealis Aab
Spectral type	F9V / G1V
B−V color index	0.546 ± 0.023
Variable type	RS CVn
Sigma Coronae Borealis B
Spectral type	G1.5V
B−V color index	0.584 ± 0.025
Sigma Coronae Borealis Cab
Spectral type	M2.5V / ~M6V
Variable type	BY Dra?
Astrometry
Sigma Coronae Borealis Aab
Radial velocity (Rv)	-13.03 ± 0.11 km/s
Proper motion (μ)	RA: -263.39 ± 0.93 mas/yr Dec.: -92.67 ± 1.31 mas/yr
Parallax (π)	43.93 ± 0.10 mas
Distance	74.2 ± 0.2 ly (22.76 ± 0.05 pc)
Absolute magnitude (MV)	4.35 ± 0.02 / 4.74 ± 0.02
Sigma Coronae Borealis B
Radial velocity (Rv)	-14.70 ± 0.11 km/s
Proper motion (μ)	RA: -289.0 ± 3.0 mas/yr Dec.: -85.1 ± 2.8 mas/yr
Absolute magnitude (MV)	4.64 ± 0.01
Sigma Coronae Borealis Cab
Proper motion (μ)	RA: -277 mas/yr Dec.: -69 mas/yr
Parallax (π)	45.40 ± 3.71 mas
Distance	72 ± 6 ly (22 ± 2 pc)
Absolute magnitude (MV)	10.54 ± 0.09
Orbit
Primary	Sigma Coronae Borealis Aa
Companion	Sigma Coronae Borealis Ab
Period (P)	1.139791423 ± 0.000000080 days
Semi-major axis (a)	1.225 ± 0.013 mas
Eccentricity (e)	0
Inclination (i)	28.08 ± 0.34°
Longitude of the node (Ω)	207.93 ± 0.67°
Semi-amplitude (K1) (primary)	61.25 ± 0.21 km/s
Semi-amplitude (K2) (secondary)	63.89 ± 0.22 km/s
Orbit
Primary	Sigma Coronae Borealis Aab
Companion	Sigma Coronae Borealis B
Period (P)	726 ± 62 years
Semi-major axis (a)	5.26 ± 0.35″
Eccentricity (e)	0.72 ± 0.01
Inclination (i)	32.3 ± 4.1°
Longitude of the node (Ω)	28.0 ± 0.5°
Periastron epoch (T)	1852.2 ± 1.5
Argument of periastron (ω) (secondary)	273.3 ± 6.8°
Orbit
Primary	Sigma Coronae Borealis Ca
Companion	Sigma Coronae Borealis Cb
Period (P)	52 years
Semi-major axis (a)	0.111 ± 0.003″
Eccentricity (e)	0.36
Inclination (i)	59°
Longitude of the node (Ω)	30°
Periastron epoch (T)	1963.0
Argument of periastron (ω) (secondary)	127°
Details
Sigma Coronae Borealis Aab
Mass	1.137 ± 0.037 / 1.090 ± 0.036 M☉
Radius	1.244 ± 0.050 / 1.244 ± 0.050 R☉
Temperature	6050 ± 150 / 5870 ± 150 K
Rotation	1.157 ± 0.002 days
Rotational velocity (v sin i)	26 ± 1 / 26 ± 1 km/s
Sigma Coronae Borealis B
Mass	0.995 ± 0.027 M☉
Radius	1.02 ± 0.07 R☉
Surface gravity (log g)	4.43 ± 0.06 cgs
Temperature	5821 ± 44 K
Metallicity [Fe/H]	-0.06 ± 0.03 dex
Rotational velocity (v sin i)	2.5 ± 0.5 km/s
Sigma Coronae Borealis Cab
Mass	~0.45 M☉ / ~0.1 M☉
Other designations
17 Coronae Borealis, Gliese 615.2
Sigma Coronae Borealis AabB: HIP 79607, GJ 9550
Sigma Coronae Borealis Aab: Sigma2 Coronae Borealis, TZ Coronae Borealis, HD 146361, TYC 2583-1846-1, HR 6063
Sigma Coronae Borealis B: Sigma1 Coronae Borealis, HD 146362, TYC 2583-1846-2, HR 6064
Sigma Coronae Borealis Cab: HIP 79551, GJ 9549
Database references
Sigma Coronae Borealis AabB
SIMBAD	data
Sigma Coronae Borealis Aab
SIMBAD	data
Sigma Coronae Borealis B
SIMBAD	data
Sigma Coronae Borealis Cab
SIMBAD	data

Sigma Coronae Borealis (σ CrB) is a star system that lies approximately 74 light-years away. The system is composed of a bright visual binary where the primary is a spectroscopic binary and a further astrometric binary at wide separation, making it a rare quintuple system.

Component discovery

First measures by Herschel, see oldest literature

Sigma Coronae Borealis was one of the first visual binaries discovered, due to the brightness of the system. The pair has been designated Struve 2032, though as the first observation in the Washington Double Star Catalog (WDS) dates to 1781 the pair has evidently been known prior to Struve's birth. Over the two-and-a-half centuries since the pair has displayed prominent orbital motion, indicating that they are a physical binary. Though only about a broad arc has been seen, enough of it has been observed to constrain the binary orbital period to be approximately 700 years, making Sigma Coronae Borealis AB one of the longest period visual binaries with a well-determined orbit.

Considering their distance and orbital period, the separation between Sigma Coronae Borealis A and B is unexpectedly large; At 74 light-years a semimajor axis of 5.26" translates to over 100 AU, making the binary's orbital period considerably shorter than expected. Using Kepler's laws to derive the mass sum of the pair indicates a total mass of 3.2 ± 0.9 M_☉, confirming that there is an excess of mass in the binary. The most common explanation for this is that one of the components is a tighter binary, which is the case here; The primary component is itself a 1.1-day binary, consisting of two almost equal-mass stars at the F/G boundary. Due to their short orbital period, the two stars are synchronously rotating, which in turn leads to RS Canum Venaticorum variability, where the subsystem's brightness varies by 0.05 magnitudes due to large stellar spots rotating in and out of view as the stars orbit each other. The binary has been resolved by the CHARA array, making it one of the smallest separation binaries to have been resolved.

References

[[Category:Corona Borealis (constellation)] [[Category:Bayer objects|Coronae Borealis, Sigma] [[Category:Flamsteed objects|Coronae Borealis, 17] [[Category:Objects named with variable star designations] [[Category:Henry Draper Catalogue objects|146361] [[Category:Hipparcos objects|079551] [[Category:Gliese and GJ objects|0615.2] [[Category:HR objects|6063] [[Category:F-type main-sequence stars] [[Category:G-type main-sequence stars] [[Category:M-type main-sequence stars] [[Category:Multiple star systems] [[Category:Spectroscopic binaries] [[Category:Astrometric binaries]

Star systems within 70 – 75 light-years

HIPPARCOS ONLY

Notes:

• Epsilon Ceti (HIP 12390) is missed because it has quite a poor-quality parallax. The star is a 2.65-year binary of similar magnitudes, causing significant photocentric orbital motion during the 3-year Hipparcos mission. Several attempts at improving upon the Hipparcos parallax have been attempted, generally agreeing on ~40 mas but still with errors of 1 or 2 mas. Recently, Docobo & Andrade (2013) calculated a dynamical parallax of 41.43 ± 0.68 mas, consistent with and more precise than attempts made with Hipparcos data. This is used in preference of the 2007 Hipparcos solution (46.55 ± 2.53 mas), and corresponds to a distance of 78.7 ± 1.3 ly, pushing the system to the next starbox.

• Pi1 Umi consists of HD 139777 (HIP 75809, parallax = 45.77 ± 0.37 mas) and HD 139813 (HIP 75829, 46.48 ± 0.49 mas). The average parallax (46.13 ± 0.36 mas) is used. The system appears to be young, with Log R'HK = ~-4.4. The image used in SIMBAD makes A appear to be binary, but this is probably not real. The WDS lists both components as spectroscopic binaries, but this does not seem to bear true (constant RVs). WDS-C is unrelated.

• HD 145825 (HIP 79578) is a low-amplitude SB1, with data from the AAT not yet covering an orbit of the companion and currently non-public HARPS data in the archive. Entirely possible that the companion is stellar.

• HD 210277 (Gliese 848.4, HIP 109378) is moved from 69.4 ± 1.2 ly to 70.3 ± 0.7 ly by the new Hipparcos reduction. Subgiant status is questionable; log g of 4.3 is below main sequence but above subgiant, so IV-V is technically more accurate.
  Okay, luminosity is apparently solar, so I'm moving it to the dwarf grouping.

• Gliese 416 (HD 97233, HIP 54677) has the remark of "also binary" in SIMBAD. There aren't any apparent references to this in literature, but a look at historic RVs show significant variation. Looking at the ELODIE archive velocities confirms this, and a secondary spectrum is even resolved at maximum velocity! The CCF depth ratio at the two times that the secondary is resolved is about 10:1. A fit to the primary's velocities finds a period of 2500 ± 300 days, eccentricity = ~0.5 and a minimum mass ratio of about 0.7. At maximum velocity, the primary's velocity reaches about 11 km/s while the secondary's reaches about -15 km/s; (11/15) = ~0.7, which indicates a near edge-on orbit.
  Oh! The system was resolved by Beuzit et al. (2004). They refer to a CORAVEL orbit, but it's not in the SB9? Anyway, they write "Modern spectrographs will easily detect the two components at the next periastron in early 2005, and it will then produce two accurate masses." Right you were!

• HD 98281 (Gliese 423.1, HIP 55210) has been observed by HARPS fairly heavily under the GTO sample. Though it is not strongly active (log R'hk = ~-4.9) the radial velocities show strong correlation with the bisector width. The periodicities in the bis are 39.5 days (rotation), 210 days (intermediate cycle, not well understood) and 2800 days (magnetic cycle). The former two are well reflected in the RV and the magnetic cycle is well reflected by a trend. The residuals of the RVs show modest periodicity, with a period of 15ish days from a linear removal of correlation but periods of 7ish or 10ish days (aliasing) from sine fitting.

• The tertiary to Gliese 857.1 (HIP 110640) appears is a white dwarf (shouldn't there be a "white dwarf" notation rather than just "star"? Or maybe "degenerate star", because maybe neutron stars). The primary's brightness and colours are consistent with a K5V star, rather than an M0V star.

• In the opposite case than the above, GJ 3059 (HIP 3813) seems to be an M0V star from it's colours rather than a K7V star.

• NQ UMa has colours intermediate between G9V and K0V. It is rounded to K here, but a G spectral type is not unlikely.

• Gliese 60 (HIP 7372)'s parallax is from Soderhj;ekf;f 1999 (Visual binary orbits and masses post Hipparcos), as the 2007 solution struggles with the binary orbit. System is quadruple; 2 K dwarfs of which one is an EB with another K dwarf orbited by an M dwarf.

• HD 7693 (Gliese 55.1, HIP 5842) is missed because it is bound to Kappa Tucanae, and that star's parallax is larger.

• PX Virginis is a astrometric-spectroscopic binary. It has HARPS measurements, which might be interesting to look at.

• HIP 111715 is missed because… well… it has a parallax of 46.00 ± 16.14 mas. There is enormous contamination from the brighter HIP 111708, and the two seem to be unrelated (with particular help from the WDS). HIP 111715 has a very low apparent proper motion, and indication of the unreality of the large parallax can be seen by comparison with the 1997 parallax of -5.87 ± 22.46 mas. The crux here is, this star is likely much more distant than the 2007 parallax suggests.

• The K7V Gliese 542.2 (HIP 69962, parallax = 45.97 ± 1.59 mas) is bound to the F7IV Iota Virginis (HIP 69701, parallax = 44.97 ± 0.19 mas), and both components are a close binary (primary astrometric and partially radial velocity, secondary optical and interferometric). The separation between primary and secondary is about 45 arcminutes(!)

• HR 784 shows very large radial velocity variations. Will investigate.
  Okay, the star is definitely a spectroscopic binary. I could only scrounge out seven radial velocities with times - four from Abt (1970) and three from the ELODIE archive. As of such, the sampling sucks, so the period is not greatly determined. Still, there is an extremely strong pileup of periodogram peaks in the vicinity of 35 days, with the best being at about 34.965 d. The semi-amplitude is about 10 km/s, and with an assumed mass of 1.17 solar masses for the primary the minimum secondary mass is about 0.16 solar masses, which is impressively small. Given that an astrometric motion is not detected by HIPPARCOS like in Rho Coronae Borealis (whose companion is definitely a star, unlike what the article currently suggests), if the orbital period is correct then the true mass cannot be too much larger than minimum.

• HR 4767 is intermediate between F9V and G0V. The former is more common, so it is used here.

• GJ 9256 is the G4-5V HD 68017 (HIP 40118), which was recently discovered to have an M5V companion at ~10 AU seperation. This star is on the Keck-HIRES RV survey, so the star will be an excellent test of stellar models and characteristics (and for a an Fe/H = -0.4 star, too!)

• HR 4134 (HIP 51523), at Fe/H = ~-0.5, is occasionally referred to as a subdwarf. Bizarrely, its log g indicates that it is a subgiant but its luminosity does not, but this is likely related to the low metallicity; it is kept in the main sequence here for compliance. The star has an ~M5 companion from 2MASS and WISE data.

• GJ 4057 (HIP 90265) is found to be a K7.5 star, which is a significant ~0.25 magnitudes fainter in the B-V than the previously found M0 spectral type.

• MN UMa is Gliese 417, one of the first identified binaries with solar-type and brown dwarf components. The companion has been resolved as a very close (2.9 AU) binary itself, both components being mid-L.

• GJ 3257 (HIP 18413) is an ~8 AU binary with an early M-dwarf

• Gliese 455.1 (HIP 59000) is a wide CPM with a faint mid M-dwarf, and is an astrometric binary with a probable brown dwarf.

• Alpha Hydri is an astrometric binary with a period of about 2 years. No spectroscopic orbit has been published, and even though the star is on the HARPS early-type sample the velocities are dominated by what appear to be pulsations and sporadic biswidth incapability on a several km/s level, making them difficult at best.

• GJ 9784 (HIP 110951) is in pretty much the same situation as GJ 4057.

• The extremely faint HIP 79551 is Sigma Coronae Borealis C. It is combined with the main component.
  Instead of using either HIPPARCOS parallax (which have fairly large errors, likely due to the bright secondary, and bring the system closer than 70 ly), the exquisite parallax of 43.93 ± 0.10 mas from Lestrade et al. (1999) is used. This places it between HIP 48447 and HIP 9829 in the frame of the new Hipparcos reduction.

• Gliese 793.1 (HIP 101382), a metal-poor spectroscopic binary, has colours and spectroscopic temperatures at about the top of K. A spectral type of G9 is adopted by SIMBAD, but K0-1 is likely more appropriate.

• Nu Octantis' parallax is from Ramm et al. (2009)'s HIAD analysis. The star is a 1050-day spectro-astrometric binary, which also shows a 417-day variation (5:2 resonant with the binary) variation which would be consistent with a planet; however, dynamical constraints make the purported planet unstable if prograde with the binary and must be retrograde to be real, which is exceedingly unlikely (along with a planet being in such a tight binary in the first place). Morais & Correia (2012) posited an alternative explanation for the excess RV variation in that the secondary is itself a precessing binary. More data is needed to distinguish between the two solutions (and parametrise the second one), but the latter hypothesis is considerably more feasible than the former and is therefore tentatively included here.

• Gliese 812.1 (HIP 103458) has an Fe/H of -0.6, so it should be a grazing subdwarf; however, it seems slightly evolved, so it lies at about the main sequence.

• Gliese 520 is a triple system, with a ~300 year visual binary of similar spectral types and a wide tertiary. The combined colours of AB are consistent with a K7.5-8 star which should not be correct, but K8 is consistent with the primary's absolute magnitude.

• GJ 3468 (HIP 54704) is a slightly metal-poor (Fe/H = -0.06) G8.5 dwarf.

• Gliese 773.3 (HIP 98416) is a problematic visual binary. It has an orbital period of about 5 years, which means that there is significant change in motion during the 3-year HIPPARCOS mission; still, a good parallax is yielded that is in agreement with previous measures. Attempt to make a RV-visual orbit failed, with reason likely relating a low inclination on the sky. Colours and absolute magnitude are consistent with a G0-1V star (with indication of slight evolution from log g), as opposed to an F8V star.

• Gliese 609.2 (HD 144287, HIP 78709) is an eccentric 12 year SB1 that was also resolved by Beuzit et al. (2004) (see Gliese 416). The HIPPARCOS B-V suggests a spectral type of G9, perhaps with a little redenning from the companion. The star is also, bizarrely, on the Keck and Lick planet search samples; no idea why, seeing as they are anti-binary and the orbit is in the SB9.

• GJ 9390 (HD 105590, HIP 59272) has stochastic HIPPARCOS solutions, likely due to contamination from the relatively bright (companion) secondary. As of such, the parallax is poor, but it is still better than the previous values. Though the only log g determination indicates that it is a subgiant, the absolute magnitude is consistent with a G3V star. The WDS references spectroscopic binarity, but like Pi1 UMi this does not seem to be real; there is no orbit in literature or SB9, and the historic RVs are consistent to a few km/s. WDS-C is unrelated, and has drawn very close (10") due to the system's proper motion.

• Unlike what the current article would have you think, Mu Cygni's Mu1 and Mu2 are a physical binary, consisting of an F6-7 star and a G2(?) star. The primary is rather over-luminous for an ~F7 star, which is why I put it in the subgiant grouping.

• Gliese 307.1 (HIP 41484) is a possible member of the Wolf 630 (i.e: Gliese 644/643) moving group (see Bubar and King (2010))

• GJ 3428 (HIP 34414)'s colours and spectroscopic temperatures indicates a spectral type of K2, vastly discrepant with the currently adopted G5.

• With a short timespan and failure to resolve the pair more recently, the relationship of HIP 20222's visual companion is currently unknown.

• Epsilon Cygni (HIP 102488) is a long-period SB1, and has four companions in the WDS. WDS-Ab does not seem to be real, and WDS-B is non-CPM; the last two, however, are somewhat confused. WDS-C was discovered in 1959 and has three observations. It seems to be CPM, with literature up to the '90s referencing confirmation of this, but it does not have PM values in the WDS. Meanwhile, WDS-D was discovered in 1999 and has two observations; this companion does not appear to have been much noticed, but it has PM values in the WDS that are consistent with that of the primary. It is probable that the two are real companions, so they are included in the star count.
  Something interesting is that Tokovinin and Lepine (2012) list a white dwarf candidate companion to Epsilon Cygni (under the HIP number), with a separation of 92 arcseconds. They indicate that it is the C component, but that one has a sep. of 78-9 arcseconds; however, WDS-D has a separation of 92-3 arcseconds, so it is likely supposed to be that component. If this is correct, then Eps Cyg consists of a KIII star, an unobserved star of spectral type approximately <F (if MS), a late K-to-early M-dwarf, and a White Dwarf!
  It is also worth noting that the SB companion is highly eccentric. Kozai oscillations are an attractive solution to this, but in the system's current state this seems undoable - but with a WD component, kozai oscillations could have occurred before mass loss. WD modelling can provide modestly accurate precursor masses, and with the potential to get an accurate mass of the primary from the SB considering that spectral modelling for giants… sucks, Epsilon Cygni could be an interesting testbed for stellar dynamics and models…

• Gliese 593/591 (HIP 76382/76375) is a triple system, with the primary being a extremely well-studied 55 year visual binary (WDS-AB) and a wider CPM tertiary (WDS-C). The two HIP numbered components have neatly similar parallaxes (A = 44.83 ± 0.60 mas, B = 44.69 ± 0.58 mas), and like Pi1 UMi the average value (44.76 ± 0.37 mas) is used, with an augmented error (i.e: the independent values are pushed away from their average by half their error value). WDS-D and -E are non-physical, with the former being a galaxy (?!). The system is, bizarrely, an SMR with an Fe/H of 0.2-0.3(!) The tertiary is constant to 10 m/s from the ELODIE archive, and is on the Keck sample and Eta-Earth sample.

• GJ 4157 (HIP 102264) shows large RV variations. It is likely an SB with period somewhere upwards of 400 days, and a semi-amplitude likely no more than 10 km/s. Unlike HR 784, I cannot investigate this one much further.
  Chini et al. (2013) find that a little-studied mid-K star at 18" is CPM from 2MASS and WISE images, and agree that the primary is an SB1.

• HD 254229 has a similar-but-different proper motion to the closeby G 103-29. The distance for the putative companion, 85 ± 18 ly, is consistent with HD 254229's distance (72.9 ± 5.4 ly) to 1σ.

• AK Pictoris (HIP 31711). This system is a member of the AB Doradus Moving Group, which complicates the solidarity of CPM stars because there will be many non-bound stars moving in the same direction. In this case, AK Pic is a close binary (1 arcsecond) consisting of a G1.5V star and a ~K2V star that displays prominent orbital motion, and has a rather wider tertiary in the K6V HIP 31878 (800 arcseconds). With an approximate physical separation of 0.26 ly, the two (treating A as one object) are probably bound, but weakly. The more difficult-to-judge case is in G1V HD 45270 (HIP 30314). Their mutual separation is comparatively enormous, with an approximate physical separation of 2.79 ly. Still, Shaya's probability that that it is bound is 1/1, so it may be an extremely fragile bound component.
  The three components observed by Hipparcos have fairly sizeably different parallaxes: (AB) = 46.96 ± 0.81 mas, (C) = 44.74 ± 0.91 mas, and (D?) = 42.05 ± 0.27 mas. Though there is the possibility that HD 45270 does not lie at the same distance as the other components, it can be assumed that ABC have the same distance. Their average value, 45.85 ± 1.08 mas, is used here.

• GJ 1259 (HIP 103256) is a mid-close SB1. Though there apparently is no published "proper" spectroscopic orbit, Halbwachs et al. (2003) present a period (2173.3 d), an eccentricity (0.46) and a rather small semi-amplitude (1.93 km/s). With data from Tokovinin (1992) and the ELODIE archive (and the mass of 0.73 solar masses), the secondary's minimum mass is only about 90 Jupiter masses - not much above the hydrogen burning limit.

• GJ 4317 (HIP 114859) has an absolute magnitude about 4 magnitudes below the expected value, given a spectral type of K3.5 from the Hipparcos B-V. This is very extreme, and strongly indicates that it is a subdwarf even without a metallicity value. The star is the primary of a close CPM with a somewhat fainter star, which raises some worry about contamination; however, all other apparent magnitude values are at about 10 and the parallax from the Gliese catalogue is consistent with the HIPPARCOS one, so the faintness must be real.

• Gliese 186.1 A (HIP 23437) is in a similar situation to HD 145825.

• EZ Ceti (HIP 8486) is missed because it is bound to Chi Ceti (HIP 8497), and that star is more distant.

• 94 Ceti A seems to be being observed at a peculiar stage of its evolution: it has a low log g for its spectral type, an overly high luminosity and a large inferred radius, but due to the narrowness of the banding of luminosity classes it lies between V and IV. The star system is metal-rich, so there is some effect of cooling, which might bring the star closer to a dwarf luminosity.

• HIP 78739 is missed. It is the fainter secondary of a 10" binary, which itself forms a wide companion to the closer triple of Xi Scorpii, making a rare quintuple system. This star is missed because the other components have slightly smaller parallaxes: compared to a parallax of 44.25 ± 4.80 mas, HIP 78738 has a parallax of 39.59 ± 3.49 mas and Xi Sco A (HIP 78727) has a parallax of 37.0 ± 1.2 mas (from Soderhjelm (1999), as the multiplicity contaminated the data so much that analysis failed).

• Gliese 275 (HD 59468, HIP 36210) has an enormous number of HARPS measurements.
  Okay, this is an interesting one! The star appears to be a ~1.5 m/s variable, apparently from at least two periodicities that are both sub-m/s.

• Psi¹ Draconis forms a wide visual binary, consisting of (A =) HIP 86614 and (B =) HIP 86620. Both have consistent parallaxes, so the average is used here. As shown on the current article, Psi¹ Draconis A has a brown dwarf candidate from radial velocities, though the orbit is unclosed; however, in the abstract of Kisselev et al. (2009) it is written that "A perturbation with amplitude 0.3″ and period 40 yrs has been detected in the orbital motion of the system ADS 10759 {Psi¹ Draconis AB}, possibly indicating the presence of an invisible satellite with a mass of the order of 0.4 M sun." The radial velocity trend and the variation in separations between the visible components are probably the same, so this system is triple.

• HD 3125 C (HIP 2715) is missed because of contamination; it is bound to HD 3125 AB, where the primary (HIP 2713) has a much smaller parallax.

• Alpha Librae B (HIP 72603) is missed because of the parallax error; Alpha Librae A and KU Librae (Alpha Librae C) have slightly smaller parallaxes, and their average leads to a distance of about 76 ly.

GLIESE ONLY

Notes:

• GJ 9127 is missed because it seems to be a Pleiad.

• GJ 1022 is missed as Jao et al. (2011) found a slightly larger, more accurate parallax. This star has a very high proper motion, so it might be a halo member.

• GJ 4325 is in the same situation as the above, except with Riedel et al. (2010).

• GJ 3964 is ditto, except this time with Jao et al. (2005).

• GJ 4035 is missed because it is a giant (log g = 3.25), so it must be much more distant than the parallax suggests. It is on the Keck sample, and is an SMR (Fe/H = 0.3) - something relatively rare for giants.

• GJ 3730 has a better, larger parallax in Shkolnik et al. (2012)

• For GJ 1159 A, SIMBAD lists a lower parallax (39.9 ± 1.0 mas), referencing Reid & Cruz (2002). This paper in turn references Tinney (1996), but this paper does not include the star. Though this parallax only ~1σ lower than the Gliese parallax, without a valid reference it cannot be used.

• It is not entirely clear which stars are being referenced under Gliese 863.1 B and C; B is probably WDS-Ab, while C, given that the other WDS components are non-CPM, is probably not a physical companion. The primary has a HIC entry (111293) but not a HIP number, as according to Soderhjelm (1999), the wrong object was observed by Hipparcos. A's B-V is ~K7.

• GJ 1017 seems to be a bizarre star; despite being 12th magnitude it is a HIP object, with its Hipparcos parallax of 11.01 ± 3.15 mas being vastly lower than the Gliese parallax. Its B-V is ~K2.5, which makes it under-luminous to 2σ; given its high proper motion despite its distance, it is plausibly a halo star and hence a subdwarf, which would explain its faintness.

• GJ 9132 is missed because it is definitely a Pleiad; the star lies close to Alcyone. It is a close binary, which is plausibly physical.

• There is nothing present at the SIMBAD image of GJ 3096, despite the co-ordinates being correct.

• GJ 3189 is missed due to conflicting parallaxes; the higher van Altena et al. (1995) parallax better fits expectations for a 13th magnitude sdM4.5 star.

• GJ 3174 also has a Shkolnik et al. (2012) parallax.

• GJ 3629 has a parallactic distance of 72.5 ± 15.1 ly and a photometric distance of 71.7 ± 9.8 ly, the latter of which is used here (maybe I should pay more attention to photometric distances; I missed one in this starbox so far, but I'll get back to that). The star has a BD companion at 4 AU.

• GJ 3577 has a photometric distance in Shkolnik et al. (2012), be it a poor one.

• Gliese 200.1 is 4.2 magnitudes fainter than expected for a K5 dwarf at its parallax to 11σ, so it is not as close as it seems. Still, it is quite high proper motion, so it may be of the old disk, but is probably not metal-poor enough to explain its faintness. It is not included here.

• Both Gliese 119 A and B are HIPPARCOS stars, but their faintness and relative brightness make their HIP solutions very poor. Smart et al. (2010) measured a parallax for A of 59.9 ± 5.0 mas, which is about 4σ higher than the Gliese parallax. The Gliese parallax suggests an absolute magnitude of a K8 star, while the TOPP parallax suggests M0.5; the star's colours are around K7-9, so the Gliese parallax is used here. Still, this is not to high significance and a higher-precision parallax is needed to solve this issue.

• GJ 9124 is missed because it is also a Pleiad.

• Gliese 784.2 B is a WD, either DA or DC. It is apparently an eclipsing binary, Though the eclipse depth does not seem to be that large.

• GJ 4064 is missed due to conflicting parallaxes. Both parallaxes make the star too luminous for an M3.5 dwarf.

• GJ 3742 has different proper motion to GJ 3741, so they are likely not bound. Still, both have quite high proper motion, so they are probably both nearby.

• GJ 3660 again has conflicting parallaxes, but this time the Gliese parallax suggests an absolute magnitude close to expected for a M1.5-2 dwarf. The star's CPM companion, GJ 3661, has colours which suggest that it is somewhat hotter than the primary, yet is fainter than it; perhaps it is a cool white dwarf or something.

• GJ 3067 is far too faint for an early K dwarf at its parallax; owing to the large error on it (± 20 mas), it is not included here.

YALE ONLY

Notes:

• PLX 1583.01:
  

B-V = 0.86* = K1* (likely inaccurate B, not used)
J-H = 0.617 = M0
H-K = 0.211 = M0.5
V-I = 2.04 = M1
V-K = 3.93 = M0.5
Average spectral type = M0.5 ± 0.5
Spectral type absolute magnitude - apparent magnitude relation gives distance of 145 ± 20 ly. Indicative, but not sturdy; follow-up would be useful.

• PLX 891.01:
  

B-V = 1.58 = M3.5
J-H = 0.489* = K3* (?)
H-K = 0.26 = M3
V-I = 2.37 = M3
V-K = 4.255 = M2
Average spectral type = M3 ± 0.5
Brightness distance is 70 ± 20 ly, which supports the parallax rather nicely. Not clear why the J-H is so discordant.

• PLX 4444.01:
  

B-V = 1.42 = K9
J-H = 0.55 = K4.5
H-K = 0.273 = M3.5
V-I = 3.08 = M4.5
V-K = 4.853 = M3.5
Average spectral type = M1 ± 5 including all, M4 ± 0.5 including only last 3
There is clearly some kind of disparity between the colours, which may be physical as it occurs twice independently. The early spectral type gives a distance of 220 ± 210 ly - not meaningful - while the late one gives 60 ± 20 ly, which is in agreement with the parallax.

• PLX 5164.01:
  

B-V = 1.1 = K4
J-H = 0.535 = K4
H-K = 0.232 = M2
V-I = 2.8 = M4
V-K = 4.45 = M2.5
Average spectral type = K9.5 ± 4.5 including all, M3 ± 1 including only last 3
There is similar discord between colours as that seen in PLX 4444.01 seen in this star. The early spectral type gives a distance of 270 ± 220 ly - not meaningful - while the later one gives 100 ± 50 ly - not much better. Follow-up needed.

Star systems within 65 – 70 light-years

HIPPARCOS ONLY

Notes:

• At ~M9, Gliese 660.1 B is apparently a hot BD, though as it is so close to the limit it is difficult to be certain.

• GJ 4024 was resolved into a binary by Horch et al. (2011), but it is not yet known if it is physical. At a low galactic latitude, the star lies in a crowded field, so it can easily be a background object.

• HR 3220 is a blue straggler, caused by mass transfer when its now-WD companion ended its gianthood. The star is evidently evolving, so its spectral type is F5V-IV. Its Hipparcos solution is stochastic.

• GJ 3863 is a UMa MG member.

• MV Draconis is apparently a Hyades member, though it is very distant from the cluster.

• Gliese 401 is an odd one; first, it is a 7" binary with a WD. The 1997 HIP solution is stochastic, negative, and very poor quality, but the 2007 solution is not unusual. The parallax is very inconsistent with both the Gliese (80 mas) and Yale (30 mas) parallaxes, but the resultant absolute magnitude fits very well for its M0V spectral type. The system has an enormous proper motion (2"/yr), suggesting that it is halo system.

• In an odd case, Gliese 11's Gliese parallax is more precise than the Hipparcos one. They are very consistent, so the Gliese one is used here. The system is a mid-long visual binary.

• Gliese 292.2 has a B-V of G8, not too different from NStars' K0. At Fe/H = -0.8, the star is a subdwarf, apparently already evolving based on its surface gravity. The star is a 450-day SB1 with a secondary minimum mass of ~0.2 solar masses, making it binary; additionally, the Hipparcos solutions indicate that the star is a resolved multiple indicating that it is a CPM binary, though as it is not seen in POSS-I and -II images the companion must be close. Given that this does not seem to be referenced in literature at all, this is considered tentative.

• Gliese 851.5 has colours bordering between end-K and start-M; Its B-V and J-H are ~M0, while its H-K and absolute magnitude ~K8. Given the reliability of B-V colours, it is assumed that the star is a metal-rich M0-dwarf.

• GJ 4308/4309 is a 70" CPM, consisting of two M2-dwarfs which are both Hipparcos stars. The average parallax is used.

• Alpha Caeli is a UMa MG member. It is a visual binary with an early M-dwarf. The WDS lists a resolution of the secondary into a close binary, though that requires confirmation.

• 53 Aquarii is a member of the Castor MG. It is a visual binary consisting of two similar early G-dwarfs, which has decreased in separation over the centuries since its discovery; this leads to a modestly constrained, eccentric, long-period orbit.

• EQ Virginis is an evaporated member of the IC 2391 cluster.

• HIP 83996 (Gliese 659 B) is missed because it is the secondary of a CPM binary, where the primary has a slightly higher, more accurate parallax.

• HD 35112 is a 90-year visual binary with a 11th magnitude star. The B-V is K3, markedly inconsistent with the G5 listed in SIMBAD.

• Gliese 415 has an absolute magnitude about 0.7 mag too low for a K4 dwarf. Casagrande et al. (2011) find an Fe/H of -1.38 while Gaidos et al. (2013) find Fe/H = -0.89, so the star is evidently an old subdwarf.

• GJ 4140 has a B-V indicating a spectral type of K7.5.

• Gliese 221 has a B-V spectral type of K7. It is a recently announced planet host, with a Super-Earth and a half-Saturn.

• Tau Cygni is evidently a high-order multiple. WDS-B is physical, forming a 50-year visual binary with the primary. WDS-C, D and E are not CPM, while WDS-F is. WDS-G has remained approximately consistent with CPM for a decade along with its 8" companion WDS-H. WDS-I also has proper motions roughly consistent with a companion, but has far too large a radial velocity difference, so it is apparently a background old star. Given the not-very-certain relationship of GH, it is considered tentative here.
  Muterspaugh et al. (2010) presented some astrometric evidence that there is a third object orbiting the primary, with a 900-day orbit and mass at the bottom Brown Dwarf limit.
  The Hipparcos B-V indicates a spectral type of F3.5 for the combined light of the close binary. The primary is evidently evolved, lying above the main sequence and having a low surface gravity.

• Sigma² Ursae Majoris A has colours of F6. It is about half a magnitude above expectations for a dwarf, and with a log g of ~4.15 it is apparently somewhat evolved. WDS-B is physical in an millenian orbit, while WDS-C is a background star. It is a Hipparcos star, and its parallax (~7 mas) and B-V indicate that it is an F-dwarf.

• GJ 3072 has a B-V indicating a spectral type of K8, a little different to the M0 in SIMBAD.

• Gliese 160.1 is the CPM companion to 50 Persei at 750" (~15000 AU), and is also a close binary; 50 Persei also has an acceleration solution, indicating that it is itself binary. The two have consistent parallaxes to a little over 1 sigma, but 50 Persei's is over twice as precise, so it is the one used. Shaya et al. (2011) find a 20% probability that 50 Persei is bound to Capella, despite the two being 15 degrees(!) apart. Though such a wide system - consisting of two quadruples, no less - is extraordinarily unlikely, their velocities are very similar so the two systems may be tenuously related.

• GJ 1164 (A) has a rather poor-quality parallax due to contamination from the bright companion (Δ = 1 mag) at 12". The secondary is also a Hipparcos star, and despite its 20 mas error, its parallax is consistent with that of the primary.

• GJ 3114, at the 12 magnitude, is one of the faintest Hipparcos stars. Because of this, its Hipparcos B-V is rather low-precision, so the colours listed by SIMBAD are used instead, finding a spectral type of M3.5V.

• HIP 110922 has a large parallax error due to its almost-analogous companion at ~3". Additionally, the primary has recently been resolved into a 0.2" binary, though it is not yet known if it is physical.

• GJ 1262 has a ~1100-day Hipparcos astrometric orbit solution, at the length of the mission. Raghavan et al. (2010) consider it to be false based on constant velocities (Gontcharov (2006)?), but Casagrande et al. (2011) find the star to have an RV rms of 5.7 km/s, giving it a 0% probability of being constant velocity. Based on this, it is considered a binary here. Based on its high Log R'_HK (-4.56), the star is evidently young. Its Hipparcos B-V indicates a spectral type of G7.5.

• GJ 3255 (HD 24496) A had a planet announced in an early version of Howard et al. (2010), but it was (quietly?) removed before the paper was published. It has not been mentioned since, so it is considered likely retracted. The star is a 3" binary with an early M-dwarf, while the primary is G7V.

• Gliese 336 is a tight visual binary. Its Hipparcos B-V is K8. Using the individual magnitude listed in the WDS, the primary's absolute magnitude is below 8.5, while using the combined magnitude it is slightly above it; naturally, the former is used.

• Rather unexpectedly, Aldebaran has a stochastic Hipparcos solution. The error on its parallax of 0.77 mas is still good, but markedly lower than expectations for an astrometrically-single 1st magnitude star with no close, bright companions. It is not fully single, though; WDS-B is physical, and at 13th magnitude it is an M-dwarf. WDS-CD is not physical and has long been known to be a Hyades system (Aldebaran, of course, lying close to the Hyades in the sky but being far closer than the cluster). WDS-E was only measured once in 1899 and is presumed to be non-physical. Finally, WDS-F has only two old measures that indicate it is non-physical.
  Aldebaran is noticeably red; Its Hipparcos B-V of 1.538 ± 0.008 indicates a spectral type of M3, while various measurements of its spectroscopic temperature find ~3900 K, translating to a spectral type of K8.5. Its absolute magnitude of ~-0.6 suggests, by its position on the HRD, that the B-V is more accurate, but not to high confidence; for simplicity (and definitely nothing to do with there not being an entry for M-giants), Aldebaran is included as a K-giant.
  The star is a radial velocity variabe, with a period of ~640 days. The lack of bisector variations indicates that this is not rotational variability, so it is likely caused by a planet. This has not been formally announced, so it is not "confirmed" per se.

• GJ 4024 has very poor quality stochastic solutions (2007 Π = 48.90 ± 28.18 mas, 1997 Π = 74.42 ± 41.23 mas), likely due to it being a 2.7" binary (Reylé et al. (2006)), though one that has no CCDM/WDS measures. The only other parallax is the Gliese one of 66 ± 15 mas. While formally more precise, it gives too low of an absolute magnitude their spectral type (M0V/M0V). Reylé et al. (2006) find a photometric distance of 27.2 ± 1.8 pc, which suggests a reasonable absolute magnitude. This is the adopted distance to the system, so it is not included here.

• Gamma Doradus is, obviously, the archetype Gamma Doradus variable, the type of variable which occupies the AF instability strip along with Delta Scutis. The star has an elaborate debris disk system.

• Gliese 371 is a possible Hyades member, though its UVWs are rather discrepant; it could be a stream member, or it could have had a close encounter with another star. The star to the west is background.

• HIP 105533 has a spectral type of K8 from its B-V and V-I.

• GJ 3084 has a 10 mas error on its parallax. This is probably due to contamination from the bright star close to its position at the Hipparcos epoch; checking POSS-I/II images shows that this is a background object. The Gliese parallax, with an 8 mas error, is little improvement, so the poor quality Hipparcos parallax is used. The star's colours are in some disagreement on its spectral type - again, probably due to contamination from the background star, so the Hipparcos B-V value of M1 is used.

• Gliese 586 consists of the G9V HD 137763 (HIP 75718), the K1.5V HD 137778 (HIP 75722) and the ~M5V Gliese 586 C (due to faintness, this component has no other major designations). The primary is itself an extremely eccentric (e = 0.98) spectroscopic binary with an early M-dwarf, that has also been resolved by interferometry and detected in the Hipparcos astrometry. Oddly, the 1997 reduction used an orbit for A's solution but in the 2007 reduction it is left stochastic, making the 2007 reduction of poorer quality. Still, the secondary's parallax is considerably more accurate in both cases, so it is used solely. A more physical oddity is that A is inactive (Log R'HK = ~-5), but B is very active (Log R'HK = ~-4.5). Because B has not been dropped from the Keck sample it is apparently not a short-period binary, so the cause of this activity is unclear. Similar cases with disparate activities in uninfluenced components are Zeta Reticuli and HD 16760.

• HR 8853 is another possible member of the Wolf 630 moving group. WDS-B is non-physical.

• CR Draconis is a ~4-year visual-astrometric binary consisting of two similar components. The orbit presented by Tamazian et al. (2008) finds too high of a mass for two early M-dwarfs when using the Hipparcos parallax; they ascribe it to the parallax being wrong, but it is extremely unlikely that the two Hipparcos, two Gliese and assorted other earlier parallaxes are too low by ~10 mas, so it is much more likely that the (preliminary) orbit is at fault or that one of the stars is a further binary. Again, using the primary magnitude listed in the WDS pushes it below an absolute magnitude of 8.5.

• Gliese 762.2 is a possible UMa MG member.

• Gliese 857 apparently had an acceleration Hipparcos solution suggesting a stellar companion, but this does not seem to be real as it has a constant RV (also still being on the AAT sample). The two WDS components are non-physical.

• HIP 40239 is a 0.8" visual binary with a magnitude difference of 0.7 mag, which makes contamination in the HIAD significant. As of such, both Hipparcos parallaxes are poor quality (1997 = 46.21 ± 4.14 mas, 2007 = 48.45 ± 5.34 mas). Söderhjelm (1999) finds a parallax of 53.0 ± 2.2 mas (61.5 ± 2.6 ly), which is used here. The system's colours are K8-9.

• Gliese 654.1's B-V and spectroscopic temperature (Valenti & Fischer (2005)) both indicate a spectral type of G0, rather than the F8-9 in literature. The three methods for calculating the star's age in Maldonado et al. (2010) all find young ages, averaging as 0.61 ± 0.11 Gyr, though they find that its kinematics are not of any moving group. Though the star is young, it is probably not a 0.04 mag BY Dra variable due to the relative constancy of the Hipparcos photometry (~0.01 mag).

• Gliese 292.1 (HD 64468) had a stellar companion detected by Vogt et al. (2002).

• HIP 14589 is missed because it is the secondary of a CPM where the primary has a much smaller parallax. The tertiary close to this component appears to be physical.

• YZ Fornacis' spectral type lies between K8 and M0; the B-V is M0, the absolute magnitude is K9, while Gray et al.'s spectral type is K8. K8-9 is assumed. The system is triple, with with two early M-dwarfs at 3" and 14".

• Gliese 842.2 is probably a Castor member.

• GJ 1069 is an astrometric binary, but is not recognised as such in either Hipparcos reduction. Its corrected parallax of 42.19 ± 1.47 mas (Halbwachs et al. (2000)) pushes it to the 75-80 ly starbox.

• HIP 34069 (HD 53706) is missed due to contamination, as it is the secondary of a moderately close binary. The system, which is quadruple, lies at about 50 ly.

• Gliese 176.3 (HIP 22122, HD 30501) is a low-amplitude, long period, high eccentricity binary (Sahlmann et al. (2011)). Its companion has a low mass (90 ± 12 M_J), skirting the upper brown dwarf limit. The system's parallax corrected for binary motion is almost entirely unchanged due to the long orbital period, so the 2007 Hipparcos reduction value is used here.

• 9 Ceti is a Hyades member. the star is a metal-rich G2-3 dwarf, making it quite similar to the Sun.

• HR 1686 (HIP 25110, HD 33564) is a planet host. WDS-B and -C are evidently non-physical, -B having an almost opposite proper motion to the star and a different radial velocity while -C has a small proper motion.

• Gliese 491 is a hierarchal triple system. The secondary is a 13th magnitude (early M) star at about 1" (~20 AU) that shows convincing orbital motion over 50 years, and the primary is an SB1 (Mayor et al. 1997) which has a Hipparcos astrometric amplitude indicating that it is a low-mass star (Halbwachs et al. (2000)).

• Gliese 330.1's colours are indicative of a K4 dwarf, which is considerably earlier than the M0 listed by SIMBAD. The star is fairly metal-poor (Fe/H = -0.4).

• HIP 10529 is missed due to contamination. The Hipparcos catalogue associates this star with the closeby Gliese 90 (HIP 10531), and hence models the two as if they have the same motions and parallax. Gliese 90 is itself a nearby (60.6 ly), high proper motion star, so this forces HIP 10529 to have a similar parameters. This is not representative of reality, though, as HIP 10529 has Tycho and WDS proper motions of only 4/4 mas/year (as opposed to the Hipparcos 520/-310 mas/year), and a lower parallax is supported by Fabricius & Makarov (2000) who find an a priori parallax of 4.6 ± 18.3 mas. Thus, HIP 10529 is far more distant than this starbox. As its colours are F-G-type and has a high Hipparcos parallax yet is faint, the star has been confused for a subdwarf by a few authors.

• Gliese 333.2 is a wide M-dwarf binary consisting of similar components. At 29", binarity cannot be causing the large error on the Hipparcos parallax (± 7 mas), but the value is still high even for a faint star. Oddly, the primary component does not seem to be a Hipparcos star (SIMBAD lists the 1997 reduction parallax for the secondary, which is a Hipparcos star), so observing the fainter component has not helped the astrometry. Anyway, the Gliese parallax (42.0 ± 5.1 mas) is of higher precision, so it is used here; this pushes the system to the 75-80 ly starbox.

• For Gliese 797, WDS-C is physical while WDS-B, -D and -E are not (the latter two possibly being related). The WDS lists a resolution of WDS-C into a nearly equal 0.3" (~6 AU) binary, referencing a paper that is apparently in preparation; this component is listed as tentative.
  Side note: this star is HD 197076. Why does that designation seem so familiar?

• Gliese 533 was discovered to be an SB1 by unpublished CORAVEL observations, then was resolved by Beuzit et al (2004) (like Gliese 416), and was also evidenced by non-linearity of the system's proper motion (Makarov & Kaplan (2005)).

• Kappa Tucanae is quadruple; the F-type primary has a K-type companion at 5" (100 AU) that is in a millenian orbit, and the two are separated by 319" (6700 AU) with a 1.1" (24 AU) K-type binary. The primary is about a magnitude above the main sequence, so it is assumed to be a subgiant.

• Gliese 808.2 has a variable proper motion, which is probably due to intermediate-period binarity.

• GJ 1239's WDS companion does not seem to be physical. The object looks faint (V <~15)

• Theta Draconis is a 3-day SB2 with a mass ratio of 0.38. The primary is a late F star approximately 1.5 magnitudes above the main sequence (=1.6 M_☉ from PARAM, though that seems a little high), so the the secondary should be late K-early M (0.6 M_☉ with the PARAM mass).

• GJ 3523 is a well-studied early G-subdwarf. The star has an Fe/H of -1 and is heavily evolved (i.e: subgiant, if a solar-metallicity star), making it about 11 Gyr old, of about 0.8 M_☉, and a halo member. The star does not seem to be multiple.

• The parallax for GJ 1271 found by Smart et al. (2010) is about 3.5σ discrepant from the Hipparcos value. Both parallaxes give reasonable absolute magnitudes, so it is not clear which is more correct; the Hipparcos value is used for consistency here.

• HD 26923/26913 (G0V/G5V) is a UMa system. Both stars are therefore active, which make them BY Dra variables with ~8-day rotational periods. Both components are Hipparcos stars, so their average parallax (47.19 ± 0.31 mas) is used. WDS-C and -D are not physical, and the two stars do not seem to be further multiples.

• HIP 81563 is a good 3 magnitudes too bright for the M4.5 star implied by its colours. Unlike with the Gliese parallax-only stars, it is less likely that the parallax is in error; indeed, the HIAD data is well-fitted, and not particularly remarkable. Therefore, there seemingly must be something unusual about this star to explain this discrepancy, but without an available explanation it is cautiously not included here.

• Sigma CrB (HIP 79607) is missed because Lestrade et al. (1999) found a lower, much more precise parallax (43.93 ± 0.10 mas) that pushes it to the next starbox.

• 16 Cygni (G2V/G3V) is a wide (800 AU projected) CPM double consisting of two well studied stars. The primary is a further multiple with an M-dwarf (70 AU projected) while the secondary is host to an eccentric planet, making this one of the few known high-order multiples containing a planet. The component parallaxes are consistent, so their average (47.29 ± 0.15 mas) is used. WDS-C is not physical.

• GJ 1008's B-V indicates it is K7, rather than M0 as listed by SIMBAD.

• Gliese 804 is a notable case. The 1997 Hipparcos solution included acceleration, but the 2007 solution did not. Frankowski et al. (2007) pointed out that there is an enormous discrepancy between the Hipparcos and Tycho proper motions (17σ in RA, 18σ in dec using the 2007 Hipparcos solution), which strongly suggests the presence of a close companion - perhaps of similar brightness to the primary, as the Hipparcos astrometric motion is not large and that is measured photocentrically. Indeed, while SIMBAD (unusually) does not list it, the star is in the WDS as a sub-arcsecond binary. The measured separation of the components range from at least 0.23" (Carbillet et al. (1996); 4.8 AU projected) to 0.086" (Balega et al. (2007); 1.8 AU projected), which indicates that the system has an orbital period of several years. The Δ of the stars is 1.5 mag, which is modestly compatible with the low Hipparcos detection. This is a system where an orbit can be derived with a little further study.

• 94 Aquarii (HIP 115126) is missed because Söderhjelm (1999) found a lower, more precise parallax (40.28 ± 1.51 mas vs 47.35 ± 2.47 mas) when accounting for the stars' multiplicity (triple).
  Personal note: I've done some tests on the Aab subsystem, and can suggest that the real distance to the system lies somewhat between the van Leeuwen and Söderhjelm distances based on derivation of Aa's spectroscopic mass, the RV-derived (+ visual inclination) mass ratio, and the subsystem mass sum derived from the orbit and distance. Specifically, I estimate π = 42.8 ± 0.4 mas (76.2 ± 0.7 ly), M_tot = 2.10 ± 0.05 M_☉, and with a mass ratio of 0.656, M_A = 1.27 ± 0.03 M_☉ and M_B = 0.83 ± 0.02 M_☉ (using some maths I'm very proud of). This is reasonably close to the Söderhjelm parallax, which is why I support it over the van Leeuwen one.

• 17 Cygni is quintuple. The star has long been known to have a 9th-magnitude companion at 25.5" (540 AU projected), making it a moderately wide F6V - K4V binary. Shaya & Olling (2011) found a 100% probability that the system is bound to Gliese 765.4 at 792" (16800 AU projected), which is itself multiple; the star has a similar-brightness companion in a 230-year orbit with a semimajor axis of 2.1" (45 AU projected), making it a ~K3V - ~K3V binary. From these two, WDS-J is CPM at 20.5" (435 AU projected), though the star does not seem to be present in SIMBAD. This component is 12th magnitude, so it is probably M-type.

• HIP 102300 does not have a good precision B-V colour available, so its 2MASS H-K is used instead; this gives a spectral type of M0.

• GJ 3507's B-V translates to a spectral type of G9.5. The star is kinematically associated to the Hyades. The large difference between its Hipparcos and Tycho proper motions indicate that the star has a companion (Makarov & Kaplan (2005), Frankowski et al. (2007)), which was resolved by Metchev & Hillenbrand (2009) at 0.96" (20 AU projected). The companion has a K_S magnitude of 10.28, equaling an absolute K_S magnitude of 8.65, which indicates a spectral type of about M5 (mass = 0.13 M_☉ from the paper).

• GJ 3071/1027 is quadruple. The primary is an 8th magnitude K3 dwarf with a 10th magnitude companion in a 30 year orbit (SMA = 0.465" = 9.8 AU). Then, in CPM at 1271" (26900 (!) AU projected) lies the DA5 white dwarf GJ 1027 which is itself a short-period SB with another WD. The system is not much more than a Gyr old, which when combined with the WD cooling age indicates that the progenitor to the double degenerate had a lifetime of ~0.5-1 Gyr, suggesting that it was late B-early A when on the main sequence - making this system akin to an evolved Regulus.

• Nu Octantis (HIP 107089) is missed because Ramm et al. (2009) found a lower parallax (45.25 ± 0.25 mas = 72.1 ± 0.4 ly) when accounting for its binarity.

• GJ 4206's B-V is K9, and its H-K is K8.

• 13 Ceti is triple, a 7-year F-G visual binary where the primary is a 2-day SB1.

• GJ 1048 has an L1 companion at 11.9" (250 AU projected). The system may be a member of the Castor group.

• FP Cancri (GJ 1108) has a fairly poor-quality parallax, probably due to it being a Δv ≈ 1 mag 13.8" binary. The secondary is itself an approximately equal SB2, as discussed in Shkolnik et al. (2010); the WDS notes also list an orbital period of 6.21 days for the two though with unclear source. The primary's colours are K9.

• GJ 9798 is Fe/H = -0.6. It lies most of a magnitude below the main sequence, but has not been referenced as a subdwarf; this is maintained here.

• GJ 3917 has an M-dwarf at 17.8" (380 AU projected). The primary's colours and spectroscopic temperatures are intermediate between G9 and K0, but generally lean towards the latter. The system has been referenced to be a member of both the local association (Pleiades stream; 140 Myr) and the Hercules-Lyra association (~250 Myr?), as the two groups are kinematically similar; the agreement seems to be that the system is of the former, which means that the secondary is approximately ZAMS.

• GJ 9188 has a poor quality Hipparcos B-V; the B and V listed by SIMBAD are used instead, which give a spectral type of about M1.

• GJ 2033 has a low-precision parallax as it is a Δv = 1 mag 2.6" (55 AU projected) binary. The component spectral types are about M2V/M3V.

• At 1"/yr, GJ 2085 has a very large proper motion. Its absolute magnitude is normal, though, so it does not appear to be a subdwarf.

• 40 Leonis is remarkable for apparently being an extremely wide binary; NLTT 23781 at 5230" shares proper motion, which translates to 111800 AU projected - that is, 1.8 ly. Caballero (2009) state that the secondary is a binary, but do not explain the justification; this is included tentatively here.

• HD 22094 (HIP 16582) is missed because its parallax is 0 to 1σ (46.79 ± 47.48 mas). The star has a CPM companion which is also a Hipparcos star (HIP 16583); this component has a parallax of 7.81 ± 6.73 mas, which indicates the primary is a giant. The Hipparcos solution for the primary is double, which cannot be due to the CPM companion as it is too wide; the image shown by SIMBAD appears to have double diffraction spikes around the primary, which indicates that it is a formally unresolved approximately equal-intensity binary with a separation of ~1". This system could use some attention.

• Why is Gliese 65.1 listed as a subgiant by SIMBAD?

• I Puppis' absolute magnitude puts it slightly below the main sequence, which indicates it is a dwarf.

• The visible component of Gliese 746's surface gravity is rather low, which indicates that this ~solar mass star is reaching the end of its main sequence lifetime. The star is a 22-day SB1.

Parallaxes

parallaxes (note - values are smallest to largest, to help with input in HEASARC)

4.95 - 9.95 ly = 327.80 - 658.91 mas

9.95 - 14.95 ly = 218.17 - 327.80 mas

14.95 - 19.95 ly = 163.49 - 218.17 mas

19.95 - 24.95 ly = 130.73 - 163.49 mas

24.95 - 29.95 ly = 108.91 - 130.73 mas

29.95 - 34.95 ly = 93.33 - 108.91 mas

34.95 - 39.95 ly = 81.65 - 93.33 mas

39.95 - 44.95 ly = 72.56 - 81.65 mas

44.95 - 49.95 ly = 65.30 - 72.56 mas

49.95 - 54.95 ly = 59.36 - 65.30 mas

54.95 - 59.95 ly = 54.41 - 59.36 mas

60.95 - 64.95 ly = 50.22 - 54.41 mas

64.95 - 69.95 ly = 46.64 - 50.22 mas

69.95 - 74.95 ly = 43.52 - 46.63 mas

74.95 - 79.95 ly = 40.80 - 43.52 mas

79.95 - 84.95 ly = 38.40 - 40.80 mas

84.95 - 89.95 ly = 36.26 - 38.40 mas

89.95 - 94.95 ly = 34.36 - 36.26 mas

94.95 - 99.95 ly = 32.64 - 34.36 mas

'Cause typical Hipparcos parallaxes have errors of about 0.5 mas, and that translates to several ly at these distances, the ranges of starboxes is going to have to increase to accommodate to the lower precision. 10 ly ranges seem good for a bit (past 100 ly or so), but beyond ~150 ly the distinction is definitely less meaningful, so the ranges are gonna need to increase further. Starboxes beyond 200 ly or so will probably not be useful in the Hipparcos era.

Notes

For a stellar radius R in units of solar radii, a stellar rotational period P in days, and a rotational velocity along the line of sight v sin i, one derives

$sin\,i={\frac {86400}{2\pi \cdot 6.955\times 10^{5}}}\cdot P\cdot ({\frac {v\,sin\,i}{R}})$

Where 86400 is a day in seconds, and 6.955 * 10⁵ is the radius of the Sun in kilometres.

The left-hand fraction equals 0.0197713…. A value of 0.01977 should be acceptable short-hand.

--

HD 108863 common proper motion with HIP 61011 yadda yadda yadda

"Thoughts"

Make template like list of stars in [constellation] for transit searches (OGLE, TrES, SuperWASP(-Qatar?), HATnet, CoRoT, Kepler) (including brown dwarfs, stars and false positives?) and RV searches (CFHT, Lick, McDonald, ELODIE, AFOE, Keck, CORALIE, AAT, HARPS…)

Or combined? Like (Transiting exoplanets) RV (HD 209458 b, HD 149026 b, HD 189733 b, Gliese 436 b, HD 17156 b, HD 80606 b, 55 Cancri e, GJ 3470 b) OGLE (-TR-56 b…) etc.

Probably combined for RV, but with not show for pageless stars? Maybe not.

Super ultra high-precision HARPS sample

Basic parameters:

Star	Wikipedia article	Spectral Type (Tycho B-V)	Spectral Type (Teff)	Mass (SPOCS)	Mass (other)	# Planets	Debris disk?
HD 1581	Zeta Tucanae	F7.5V	F9.5V	1.014 ± 0.036 M☉	—	—	Yes
HD 10700	Tau Ceti	G5.5V	G9V	0.799 ± 0.014 M☉	0.783 ± 0.012 M☉	5?	Yes
HD 20794	82 G. Eridani	G5V	G8.5V	0.845 ± 0.011 M☉	—	3	Yes
HD 65907 A	—	F7.5V	G0V	1.056 ± 0.036 M☉	—	—	No
HD 85512	"	K5V	K3.5V	0.712 ± 0.020 M☉	—	1	No
HD 109200	—	K1V	K1V	0.777 ± 0.026 M☉	—	—	No
HD 128621	Alpha Centauri B	K1V	K1V	0.877 ± 0.021 M☉	0.934 ± 0.006 M☉	1	No
HD 154577	"	K2V	K2.5V	0.688 ± 0.027 M☉	—	—	No
HD 190248	Delta Pavonis	G8V-IV	G5.5V-IV	0.991 ± 0.033 M☉	—	—	No
HD 192310	HR 7722	K2V	K1V	0.816 ± 0.019 M☉	—	2	No

Not-so-basic parameters (courtesy of PARAM):

Star	V (mag) (Tycho)	B-V (mag) (Tycho)	Parallax (mas) (Hipparcos)	Teff (K)	Fe/H (dex)	Mass (M☉) (PARAM)	log g (cgs) (PARAM)	Radius (R☉) (PARAM)	Age (Gyr) (PARAM)
HD 1581	4.231 ± 0.011	0.522 ± 0.011	116.46 ± 0.16	5977 ± 12	-0.18 ± 0.01	0.987 ± 0.011	4.380 ± 0.010	1.039 ± 0.018	5.028 ± 0.408
HD 10700a	3.499 ± 0.011	0.687 ± 0.020	272.96 ± 0.17	5310 ± 17	-0.52 ± 0.01	—	—	—	—
HD 20794a	4.265 ± 0.011	0.675 ± 0.020	165.47 ± 0.19	5401 ± 17	-0.40 ± 0.01	—	—	—	—
HD 65907 A	5.588 ± 0.011	0.518 ± 0.020	61.71 ± 0.21	5945 ± 16	-0.31 ± 0.01	0.911 ± 0.009	4.323 ± 0.011	1.048 ± 0.006	8.525 ± 0.501
HD 85512	7.681 ± 0.012	1.153 ± 0.023	89.62 ± 0.67	4715 ± 102	-0.32 ± 0.03	0.634 ± 0.011	4.679 ± 0.014	0.582 ± 0.012	3.798 ± 3.784
HD 109200	7.147 ± 0.012	0.838 ± 0.021	61.82 ± 0.48	5134 ± 38	-0.31 ± 0.02	0.752 ± 0.016	4.571 ± 0.019	0.722 ± 0.008	7.549 ± 3.561
HD 128621	1.33 ± 0.03b	0.86 ± 0.04b	747.1 ± 1.2	5178 ± 44	0.23 ± 0.03	0.895 ± 0.024	4.492 ± 0.026	0.862 ± 0.017	6.140 ± 3.801
HD 154577	7.401 ± 0.012	0.882 ± 0.022	73.41 ± 0.70	4900 ± 37	-0.70 ± 0.02	0.641 ± 0.011	4.658 ± 0.012	0.603 ± 0.001	6.871 ± 3.633
HD 190248	3.539 ± 0.011	0.731 ± 0.020	163.71 ± 0.17	5604 ± 38	0.33 ± 0.03	1.041 ± 0.017	4.299 ± 0.022	1.158 ± 0.025	6.899 ± 1.082
HD 192310	5.731 ± 0.011	0.881 ± 0.020	112.22 ± 0.30	5166 ± 49	-0.04 ± 0.03	0.831 ± 0.023	4.555 ± 0.022	0.831 ± 0.023	4.102 ± 3.592

^a Non-convergent. Likely related to over-confident parameter errors, probably spectroscopic.

^b Tycho measurements appear to be smeared by brightness and contaminated by proximity to Alpha Centauri A, so these values are approximations of archival ones.

"The HARPS search for Earth-like planets in the habitable zone I" data:

Star	Observations	Time span (days)	RV scatter (m/s)	log R'HK
HD 1581	93	2566	1.26	-4.93 ± 0.003
HD 10700	141	2190	0.92	-4.96 ± 0.003
HD 20794	187	2610	1.20	-4.98 ± 0.003
HD 65907 A	39	2306	1.45	-4.91 ± 0.006
HD 85512	185	2745	1.05	-4.90 ± 0.043
HD 109200	77	2507	1.16	-4.95 ± 0.018
HD 128621	171	2776	—	-4.96 ± 0.014
HD 154577	99	2289	1.05	-4.87 ± 0.026
HD 190248	86	2531	1.26	-5.09 ± 0.009
HD 192310	139	2348	2.62	-4.99 ± 0.033

"The HARPS search for southern extra-solar planets XXXI" data:

Star	Observations	Time span (days)	Mean log R'HK	Magnetic cycle?	R'HK γ	Cycle period (days)	Cycle amplitude (log R'HK)	R'HK rotational period (days)
HD 1581	127	2625	-4.954 ± 0.099	Yes	-4.953	1018 ± 49	0.099	16.7 ± 2.6
HD 10700	153	2650	-5.017 ± 0.009	No	—	—	—	37.4 ± 3.8
HD 20794	197	2694	-5.025 ± 0.009	Yes	-5.025	751 ± 157	0.007	35.4 ± 3.6
HD 65907 A	62	2609	-4.948 ± 0.021	Yes	-4.923	>~6000	0.078	14.9 ± 2.6
HD 85512	175	2705	-4.936 ± 0.114	Yes	-4.956	3793 ± 686	0.204	50.9 ± 7.0
HD 109200	118	2866	-4.976 ± 0.077	Yes	-4.950	>~6000	0.212	43.0 ± 4.6
HD 128621 (Not a GTO star)	—	—	—	—	—	—	—	—
HD 154577	118	2550	-4.974 ± 0.075	Yes	-4.959	2702 ± 364	0.129	45.8 ± 5.0
HD 190248	84	2491	-5.052 ± 0.016	No	—	—	—	41.4 ± 3.9
HD 192310	152	2704	-4.996 ± 0.106	Yes	-4.931	3792 ± 686	0.205	43.7 ± 4.9