725
Double star Struve 2398 |
|||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Observation dates equinox : J2000.0 , epoch : J2000.0 |
|||||||||||||||||||||||
AladinLite | |||||||||||||||||||||||
Constellation | Dragon | ||||||||||||||||||||||
Right ascension | 18 h 42 m 46.7 s
|
||||||||||||||||||||||
declination | + 59 ° 37 ′ 50 ″
|
||||||||||||||||||||||
Apparent brightness | 8.48 likes | ||||||||||||||||||||||
Astrometry | |||||||||||||||||||||||
Radial velocity | (−1.07 ± 0.09) (1.09 ± 0.09) km / s |
||||||||||||||||||||||
parallax | (283.95 ± 0.06) (283.86 ± 0.11) mas |
||||||||||||||||||||||
distance | (11.48 ± 0.01) Lj (3.52 ± 0.01 pc ) |
||||||||||||||||||||||
Proper movement : | |||||||||||||||||||||||
Rec. Share: | (−1311.91 ± 0.18) (−1400.02 ± 0.32) mas / a |
||||||||||||||||||||||
Dec. portion: | (1792.19 ± 0.22) (1862.41 ± 0.39) mas / a |
||||||||||||||||||||||
Individual data | |||||||||||||||||||||||
Names | A; B. | ||||||||||||||||||||||
Observation data: | |||||||||||||||||||||||
Apparent brightness | A. | 8.91 mag | |||||||||||||||||||||
B. | 9.69 likes | ||||||||||||||||||||||
Typing: | |||||||||||||||||||||||
Spectral class | A. | M3.0 V | |||||||||||||||||||||
B. | M3.5 V | ||||||||||||||||||||||
B − V color index | A. | (1.87) | |||||||||||||||||||||
B. | (2.02) | ||||||||||||||||||||||
Physical Properties: | |||||||||||||||||||||||
Dimensions | A. | (0.340 ± 0.007) M ☉ | |||||||||||||||||||||
B. | (0.261 ± 0.006) M ☉ | ||||||||||||||||||||||
radius | A. | (0.347 ± 0.010) R ☉ | |||||||||||||||||||||
B. | (0.281 ± 0.008) R ☉ | ||||||||||||||||||||||
Other names and catalog entries |
|||||||||||||||||||||||
|
Struve 2398 ( Σ 2398 , Gliese 725 ) is a binary star system in the constellation Draco . At a distance of around 11.5 light years, the components are among the closest known stars . Both stars are red dwarfs .
The components reached their maximum angular distance around 1904 at 17 ", since then their distance has been decreasing. An exact orbit has not yet been determined; estimates of the orbital period are between 300 and 400 years.
literature
- WD Heintz: The Red-Dwarf Binary Σ2398. In: PASP . 99, 1987, pp. 1084-1088.
- P. Baize: Orbital elements of eighteen visual double stars. In: Astronomy and Astrophysics . Volume 26, 1976, pp. 177-193, bibcode : 1976A & AS ... 26..177B
Web links
- Struve 2398 at SolStation
- http://www.daviddarling.info/encyclopedia/S/Struve2398.html
- http://www.richweb.f9.co.uk/astro/nearby_stars.htm
- Struve 2398 in Dra
Individual evidence
- ↑ a b LDS 1466. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed November 8, 2018 .
- ↑ a b c d e f HD 173739. In: SIMBAD. Center de Données astronomiques de Strasbourg, accessed November 8, 2018 .
- ↑ a b c d e f HD 173740. In: SIMBAD. Center de Données astronomiques de Strasbourg, accessed November 8, 2018 .
- ↑ a b P. E. Kervella, F. Arenou, F. Mignard, F. Thévenin: Stellar and substellar companions of nearby stars from Gaia DR2. Binarity from proper motion anomaly . In: Astronomy & Astrophysics . 623, p. A72. arxiv : 1811.08902 . bibcode : 2019A & A ... 623A..72K . doi : 10.1051 / 0004-6361 / 201834371 .