Scorpio Delta (δ Sco / δ Scorpio) is a star in the constellation of Scorpio , a hot giant of the spectral class B0. She also has her own name Dshubba (or Dziuba, with jabhat Arabic, “forehead” (scorpion)) or Iclarcrau or Iclarkrav.
| Dshubba | |||
|---|---|---|---|
| Star | |||
| Observational data ( Epoch J2000.0) | |||
| Right ascension | |||
| Declination | |||
| Distance | 401.3 over the year (123.1 pc) | ||
| Visible magnitude ( V ) | 2.29 | ||
| Constellation | Scorpio | ||
| Astrometry | |||
| Parallax (π) | 8.12 ± 0.88 mas | ||
| Absolute magnitude (V) | -3.16 | ||
| Specifications | |||
| Spectral class | B0.2 IV | ||
| Color Indicator ( B - V ) | -0.124 | ||
| Color Index ( U - B ) | -0.909 | ||
| Variability | γ Cassiopeia | ||
| physical characteristics | |||
| Weight | 19.7 ± 0.1 , [1] 14.6-14.9 [2] M ☉ | ||
| Radius | 5 [3] R ☉ | ||
| Age | 4.8 ± 0.2 mln. , [1] 9-10 mln. [2] years | ||
| Temperature | 28000 K | ||
| Luminosity | 14000 (bolometric) [3] L ☉ | ||
| Rotation | 181 km / s | ||
| |||
| Information in databases | |||
| SIMBAD | data | ||
δ Scorpio is located near the ecliptic , so sometimes it is covered by the Moon, and, very rarely, by the planets.
Content
Variability
The brilliance δ of Scorpio was considered unchanged until July 2000, when the visual star magnitude unexpectedly increased from 2.3 m to 1.8 m [4] . In the following months, the star's brightness changed from 2.0 m to 1.6 m [5] . The spectra obtained after the start of the flash showed that the star had dropped the shell of the luminous gas from its equatorial region. As of 2005, the outbreak continues. Although the brightness changes, it remains much higher than its previous values. In the summer of 2011, the Delta of Scorpio again flared up to 1.55 stars. led [6]
Companions
A class B companion is drawn around the star, making one revolution every 20 days at a distance comparable to the distance from the Sun to Mercury. In addition, there is a star in the system with an orbital period of at least 10 years in an orbit with a large eccentricity, which leads to close encounters with the main component [3] . The last close encounter of these two stars occurred in mid-2000, and may have caused an increase in the brightness of the main star. The possible fourth satellite is two times farther from the main component.
Notes
- ↑ 1 2 Tetzlaff, N .; Neuhäuser, R. & Hohle, MM (2011), " Hipparcos stars within 3 kpc from the Sun ", Monthly Notices of the Royal Astronomical Society T. 410 (1): 190–200 , DOI 10.1111 / j .1365-2966.2010.17434.x
- ↑ 1 2 Mark J. Pecaut, Eric E. Mamajek, & Eric J. Bubar. Scorpius-Centaurus OB Association ( The Astrophysical Journal : journal). - IOP Publishing , 2012. - February ( vol. 746 , no. 2 ). - P. 154 .
- ↑ 1 2 3 Dschubba Unreferenced (inaccessible link) . Archived November 23, 2005.
- ↑ Delta Scorpii brighter than ever ( Sky and Telescope , February 4, 2002)
- ↑ Delta Scorpii still showing off ( Sky and Telescope , June 25, 2003)
- ↑ Brightening in 2011