- Double Stars (Hya) -

And (32) Cep (13) CVn (4) Her (13) Mon (1) Sex (2)
Aql (9) Cet (1) Cyg (19) Hya (4) Oph (1) Tau (11)
Ari (8) CMa (1) Del (2) Leo (19) Ori (8) Tri (4)
Aur (27) Cnc (10) Dra (8) Lib (1) Peg (16) UMa (24)
Boo (12) Com (8) Equ (5) LMi (6) Per (18) UMi (1)
Cam (10) CrB (4) Eri (1) Lyn (18) Psc (7) Vir (6)
Cas (17) Crv (1) Gem (19) Lyr (8) Ser (2)

11 Hya (**)

Name: 11 Hya, epsilon Hya
Type: **
Constellation: Hya
Coordinates: 08h46m46.51s / +06°25'07.70"

Components:
m1 m2 ρ θ Year
SP1 AB 3m5 5m0 0.2" 241° 2018
STF1273 AB-C 3m5 6m7 2.9" 309° 2017
STF1273 AB-D 3m5 12m5 18.1" 201° 2017
STF1273 AB-E 3m5 10m8 340.5" 2015
STF1273 AB-F 3m5 10m4 406.5" 265° 2015

../images/binary-star-orbits/SP1-AB-orbit.jpg ../images/binary-star-orbits/STF1273-AB-C-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x, Bortle 6-
AB-C: Not split. Although a slight brightening was visible in the first diffraction ring, it could also have come from slight coma of the refractor.

102mm f/11, 160x, Bortle 7, SQM-L 18.8, Seeing 3/5
AB-C: 2020-03-27: The much fainter companion is well visible as an almost round knot directly at the diffraction ring of the primary component. Very nice sight. The seeing was mediocre (3/5).

152mm f/5.9, 150x, Bortle 7, SQM-L 18.8, Seeing 3/5
AB-C: 2020-03-27: The companion is immediately visible as a tiny star close to the primary component. Due to the chromatic aberration of the achromat, there is a slight tendency to outshine. Nevertheless a nice view. The seeing was mediocre (3/5).

STF 1347 (**)

Name: STF1347
Type: **
Constellation: Hya
Coordinates: 09h23m15.76s / +03°30'05.00"

Components:
m1 m2 ρ θ Year
7m3 8m3 21.1" 312° 2016
Robert Zebahl
70mm f/5.7, 22x, Bortle 6
2020-04-10: At 22x beautifully separated at moderate separation and difference in brightness. Primary component appeared white-bluish, companion slightly orange. At 44x the primary component looked more white-yellowish, the companion showed a clear tendency to orange.

STF 1348 (**)

Name: STF1348
Type: **
Constellation: Hya
Coordinates: 09h24m28.48s / +06°21'01.80"

Components:
m1 m2 ρ θ Year
AB 7m5 7m6 2.0" 314° 2018
Robert Zebahl
70mm f/5.7, 100x, Bortle 6
2020-04-10: At 67x clearly elongated, at 80x clearly visible as figure '8'. At 100x a very small difference in brightness was to be guessed, at 133x visible. Near the double star STF 1355.

STF 1355 (**)

Name: STF1355
Type: **
Constellation: Hya
Coordinates: 09h27m16.69s / +06°13'59.00"

Components:
m1 m2 ρ θ Year
7m7 7m8 1.8" 357° 2018

../images/binary-star-orbits/STF1355-orbit.jpg

Robert Zebahl
70mm f/5.7, 100x, Bortle 6
2020-04-10: At 67x clearly elongated, equally bright. At 80x detectable notch. At 100x and 133x clearly visible as figure '8'. Near the double star STF 1348.