Delta Apodis

δ Apodis
Location of δ Apodis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Apus
δ1 Aps
Right ascension 16h 20m 20.802s
Declination −78° 41 44.69
Apparent magnitude (V) 4.66 to 4.87
δ2 Aps
Right ascension 16h 20m 26.858s
Declination −78° 40 02.99
Apparent magnitude (V) +5.27
Characteristics
δ1 Aps
Spectral type M5 IIIb
U−B color index +1.680±0.110
B−V color index +1.69
Variable type LB?
δ2 Aps
Spectral type K3 III
U−B color index +1.62
B−V color index +1.413±0.012
Astrometry
δ1 Aps
Radial velocity (Rv)−12.0 km/s
Proper motion (μ) RA: −9.678 mas/yr
Dec.: −37.147 mas/yr
Parallax (π)5.2508±0.1942 mas
Distance620 ± 20 ly
(190 ± 7 pc)
Absolute magnitude (MV)−2.16
δ2 Aps
Radial velocity (Rv)−10.2 km/s
Proper motion (μ) RA: −1.817 mas/yr
Dec.: −31.511 mas/yr
Parallax (π)5.795 ± 0.0902 mas
Distance563 ± 9 ly
(173 ± 3 pc)
Absolute magnitude (MV)−1.10
Other designations
CPD−78 1092, FK5 1424, HR 6020
δ1 Aps: HD 145366, HIP 80047, SAO 257380
δ2 Aps: HD 145388, HIP 80057, SAO 257381
Database references
SIMBADδ1 Aps
δ2 Aps

Delta Apodis is a double star in the southern constellation of Apus. Its identifier is a Bayer designation that is Latinized from δ Apodis, and abbreviated Del Aps or δ Aps, respectively. Based on parallax measurements, the distance to δ1 Apodis is approximately 620 light years, while δ2 Apodis is found to be around 563 light years from Earth. They may form a common proper motion pair.

The brighter star, δ1 Apodis, has an apparent magnitude that varies from +4.66 to +4.87. It is a red giant with a stellar classification of M5 IIIb, and is classified as a semiregular variable with pulsations of multiple periods of 68.0, 94.9 and 101.7 days. δ2 Apodis has an apparent magnitude of +5.27 and is an orange K-type giant with a class of K3 III. Both stars are bright enough to be seen with the naked eye under good observing conditions. The pair have an angular separation of 103.4 arcseconds (as of 2016), which is wide enough to allow them to be seen individually by a person with good eyesight.