Gamma Arietis
Gamma Ari – γ Ari – Mesarthim – Star system in Aries
It’s a really nice shiny blueish pair. Everything beyond the visuals is confusing. By Wikipedia it’s a ‘binary or possibly trinary star system.’ Its primary A component is called γ-2, while the secondary B is γ-1. γ-2 is considered as an A2-class subgiant but it maybe has a red dwarf pair. Why not?
Even the catalogue IDs are contradicting. Wikipedia states that
- A = γ-2 = HD 11503 = HR 546 = Mesarthim
- B = γ-1 = HD 11502 = HR 545
while astronomyapi.com data is
- HD 11502 = HR 546 = Mesarthim
- no data for HD 11503 nor HR 545
Spectral classes on Wikipedia:
- A: A2IVpSiSrCr
- B: A0Vnp λ Boo or A0IV-V(n)kB8
On astronomyapi.com HD 11502 is A1p Si. By the way, what is A0IV-V(n)kB8? And what is ‘chemically peculiar’?…
I also failed to measure the separation correctly. The result is definitely wrong, about the double of the real value. I have to check my method and measure it again later.
| Object | Gamma Arietis |
|---|---|
| Observed at | Dunaharaszti, HU, 2025-09-15 23:05 |
| NELM | ~ 4.4 |
| Seeing | 6 |
| Aperture | 127 mm |
| Magnification | 171x |
| FOV | 0.4° |
| Other data | |
| PA | ~270° |
| Separation | 15.6” ?! (catalog data: 7.6”) |
Object data
| Objects | Gamma Ari A | Gamma Ari B |
|---|---|---|
| Fetched as | HD 11502 | |
| Desc. | CVn type variable star | ‘Lambda Boötis’ star, maybe a spectroscopic binary |
| RA | 01h 53m 31s † | |
| Dec | 19° 17’ 38” † | |
| Magnitude | 4.58 | 4.64 |
| Spectral class | A1p Si † |
† fetched from astronomyapi.com
