Table 2
Proper motion measurements for HD 7977.
| Year | Source and epoch | μα ⋅ cos(δ) (mas yr–1) | μδ (mas yr–1) |
|---|---|---|---|
| 1966 | SAO B1950 | –32.5 ± 8.0 | +18.0 ± 14.0 |
| 1975 | AGK3 B1950 | +4 ± 4.4 (a) | –6 ± 9.3(a) |
| 1988 | PPM J2000 | +2.1 ± 2.8 | –7.0 ± 5.6 |
| 1991 | ACRS B1950 | +2.0 ± 2.3(b) | –4.9 ± 4.9(b) |
| 1992 | AGK3U B1950 | +0.2 ± 4.71 | +1.9 ± 4.71 |
| 1997 | ACT J2000 | –4.52 ± 1.8 | –4.7 ± 2.28 |
| 2000 | Tycho-2 J2000 | –3.5 ± 2.0 | –1.8 ± 1.9 |
| 2010 | PPMXL 1991.0 | –3.3 ± 1.8 | –0.8 ± 1.8 |
| 2018 | Gaia DR2 2015.5 | 0.559 ± 0.019 | 0.014 ± 0.046 |
| 2022 | Gaia DR3 2016.0 | 0.144 ± 0.011 | 0.010 ± 0.034 |
Notes. All numbers are taken from electronic versions of the quoted catalogues included in the Vizier database (Ochsenbein et al. 2000). (a)For AGK3 proper motion errors we use the mean catalogue error of the proper motion estimated by Schwan (1985). (b)In ACRS proper motion errors for HD 7977 are not given so we apply mean catalogue errors estimated by Corbin & Urban (1989).
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