1 The Seymour & Hartkopf (1999, IAU Comm. 26 Inf. Circ., 139) orbit predicts 
 1  a separation of about 0.07" at the time of this observation; this orbit was 
 1  based on data only through 1995, however, so the pair may have closed more 
 1  than predicted. 
 2 The known companion is too faint for detection here. 
 3 The most recent orbit of this pair (Docobo & Ling, 2005, IAU Comm. 26 Inf. 
 3  Circ., 157) predicts a separation of 0.28" at this epoch; it is unknown why 
 3  the pair was not resolved. 
 4 Separation of the known close companion may have been <0.03" at the time of 
 4  this observation. 
 5 Observed with a Johnson V filter and usually a lower magnification 
 5  microscope objective due to the character of the target.  The resolution
 5  limit for this observation is estimated at 0.05". 
 6 This pair was resolved four times between 1978 and 1986 (separations 
 6  0.09" to 0.14"); however, there are also 20 published unresolved 
 6  observations between 1982 and 2004, including two 6m speckle observations. 
 7 Observed one component of a wide double/multiple. 
 8 The 1991 discovery measure of this pair (Mason et al., 1993AJ....105..220M) 
 8  remains unconfirmed. 
 9 This object was unresolved in five observations between 1988 and 1993,
 9  using techniques including visual and infrared speckle interferometry, 
 9  the HST fine-guidance sensor, and Hipparcos. The sole resolved measure
 9  (Barstow et al., 2001MNRAS.322..891B) was made in 1999 using the HST 
 9  planetary camera in the ultraviolet (197nm). 
10 Patience et al. (1998AJ....115.1972P) resolved this pair twice (~0.045") at 
10  2.2 microns on the Palomar 5m, in 1996 and 1997. Earlier observations 
10  (HST, visual speckle) were unable to detect a secondary. 
11 The known companion has too large a magnitude difference for detection here. 
12 Due to its highly-inclined orbit, the separation for this pair ranges from 
12  0.3" to 0.014" over the course of ~ 12 years. The pair was approaching 
12  closest apparent separation at the time of this observation, so 
12  presumably {rho}<0.03". 
13 The AB components of this triple were resolved in 1936 and 1937, but not 
13  recovered since then. The AB-C pair has widened to probably >1.5" at this 
13  time; the C component is also too faint to detect with the filter used. 
14 First resolved by Rossiter (1955POMic..11....1R) in 1939 at 0.20", the pair 
14  was confirmed by Holden (1972, Publ. Univ. Michigan Obs., 12, 1) in 1970 
14  at 0.18" (with a large change in position angle), but unresolved by 
14  Hipparcos in 1991 (ESA 1997, Cat. I/239). There have been no other published
14  observations. Perhaps orbital motion has brought the pair closer than 
14  {rho}<0.03" at the time of this observation. 
15 This occultation pair was marginally resolved twice in 1984 (Mason,
15  1996AJ....112.2260M); all subsequent attempts to resolve this occultation 
15  pair have been unsuccessful. 
16 This occultation pair was resolved once in 1980 at 0.365" (McAlister et al.,
16  1983ApJS...51..309M); this discovery remains unconfirmed, however, despite 
16  13 published attempts. 
17 The A component of a 5" pair is a spectroscopic triple and an irregular 
17  variable (d Ser). The pair was initially resolved in 1951 by eyepiece 
17  interferometry (Wilson, 1952AJ.....57..248W) at a separation of 0.06". 
17  McAlister & Hendry (1982ApJS...48..273M) also resolved it in 1976, although 
17  at a very different separation (0.25") and angle. Some 10 unresolved 
17  observations have been published since 1976, suggesting that the earlier 
17  resolutions may instead have been artifacts. 
18 This pair has closed steadily in recent years, from 0.21" in 1991 to 0.08" 
18  in 2001. It may perhaps have been closer than 0.03" at the time of this 
18  observation. 
19 Only six observations have been published, all between 1976 and 1989; 
19  separations have ranged from 0.16" to 0.045", as well as two unresolved 
19  observations. No clear pattern of motion has yet been discerned. 
20 This pair was resolved several times between 1936 and 1954 
20  ({rho}~0.09"-0.14"), unresolved several times between 1959 and 1964, 
20  resolved once in 1989 (0.13"), and unresolved by Hipparcos in 1991. 
20  No observations have been published since that time. 
21 The most recent published orbit (Mason & Hartkopf, 1999, IAU Comm. 26 Inf. 
21  Circ., 138) predicts a separation of about 0.054" at this time of this 
21  observation, decreasing to 0.005" by 2006.87. Periastron may have occurred 
21  slightly earlier than predicted. 
22 Only three observations of this pair have been published, indicating fair 
22  orbital motion and a decrease in separation from 67 to 50 mas between 1985 
22  and 1991. The pair therefore may well have been <0.03" in 2005. However, the
22  wider MCA 60AB pair remained nearly stationary at (~145{deg}, 0.25") 
22  between 1980 and 1998; it is unknown why this pair was not resolved. 
23 This pair was measured some 34 times between 1975 and 1999, usually in the 
23  50-70mas range of separation. No observations have been published since 
23  1999, however. Published orbits by McAlister (1980ApJ...236..522M) and 
23  Pourbaix (2000A&AS..145..215P) both give periods of about 2.25yr and predict
23  separations at the time of this observation of 0.036" and 0.044", 
23  respectively. Periastron separations for both orbits are about 0.01". 
24 Recent orbital solutions (Tokovinin, 1986SvAL...12..201T; 
24  Pourbaix, 2000A&AS..145..215P) predict a separation of about 0.052" for 
24  2005.86; it is unknown why the pair was not resolved here. 
25 Both the Aa,Ab and Aa,Ac pairs should have separations of ~0.25"; it is 
25  unknown why neither pair was resolved here. 
31 Observed one component of a wide double/multiple. 
32 The known close companion may have closed such that {rho}<0.03". 
33 The known companion has too large a magnitude difference for detection here. 
34 Observed with a Johnson V filter and and usually a lower magnification 
34  microscope objective due to the character of the target. The resolution
34  limit for this observation is estimated at {rho}<0.05". 
35 The known companion is too faint for detection here. 
36 Observed with the USNO g filter ({lambda}_eff_=560nm, FWHM=45nm). This filter
36  has the same color as the Stromgren y filter and is still fairly narrow, so 
36  the resolution limit is essentially the same (~0.03"). 
41 Orbit in need of correction
42 Not measured before (Table 1) 
43 Pleiades cluster member (Mason et al., 1993AJ....105..220M) 
44 Also known as HD 23608. Estimated {Delta}m=0.6 
45 Pair observed to investigate properties of multiple systems 
46 Hyades cluster member (Mason et al., 1993, Cat. J/AJ/106/637) 
47 Also known as HD 28305. Estimated {Delta}m=2.4 
48 While the 6th Orbit Catalog lists two possible solutions for this pair,
48  the measurement fits better the second orbit listed here 
49 Spectroscopic analysis of this pair in progress 
50 Quadrant flip necessary for this orbit 
51 Confirming observation 
52 Multiple possible orbits for this pair, none of which fits well. While 
52  correction may be necessary, the data coverage may be insufficient 
53 While the 6th Orbit Catalog lists two possible solutions for this pair,
53  the measurement fits better the second orbit listed here. Quadrant 
53  flip necessary for the second orbit
54 Also known as P 434. Estimated {Delta}m=1.5 
55 Also known as P 434. Estimated {Delta}m=2.5 
56 Also known as P 456. Estimated {Delta}m=2.5 
57 Eclipsing SB2 with third light indicated
61 Orbit in obvious need of correction
62 Not measured before (Table 1)
63 Dmag is an estimate, not a catalog value
64 Confirming observation
65 While the 6th Orbit Catalog lists two possible solutions for this pair,
65  it fits the second orbit listed here better
66 Multiple possible orbits for this pair, none of which fits well. While
66  correction may be necessary, the data coverage may be insufficient
67 Unpublished CHARA speckle measure. See Hartkopf et al.
67  (2000IAUDS.142....1H) for a description of the CHARA speckle camera and
67  a discussion of re-reduced observations
68 Unpublished CHARA non-detection. See Hartkopf et al.
68  (2000IAUDS.142....1H). The O-C columns here provide the position
68  predicted by the new orbit
69 Measure obtained with the NOFS 61-in reflector. Inadvertently omitted
69  from Hartkopf et al. (2008, Cat. J/AJ/135/1334)
70 Measure obtained with the Mt. Wilson 100-in reflector
70  (W. Hartkopf & B. Mason, in preparation)
 a System used in characterizing errors or investigating detection space
 p Pleiades cluster member (Mason et al., 1993AJ....105..220M).
 h Hyades cluster member (Mason et al. 1993, Cat. J/AJ/106/637a). 
 o New Horizon's occultation star.