Scorpius-Centaurus Association

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The Scorpius-Centaurus Association , also known as Sco-Cen , is the closest association of stars to the Sun, made up of stars of the spectral classes O and B. Like some other associations of bright stars less than 500 parsec away , it is part of Gould's Belt .

Scorpius-Centaurus Association

This star association consists of the three subgroups Upper Scorpius, Upper Centaurus-Lupus and Lower Centaurus-Crux. Their average distances range from 380 to 470 light years.

The age of the subgroups ranges from 5 million years (Upper Scorpius) to around 15 million years (Upper Centaurus-Lupus and Lower Centaurus-Crux). Many bright stars in the constellations Scorpius, Lupus, Centaurus and Crux are members of the Sco-Cen Association. Antares , the heaviest star of Upper Scorpius, as well as most of the stars in the Southern Cross and hundreds of other stars with masses from 15 solar masses down to brown dwarfs belong to Sco-Cen. The total number of stars in each subgroup is between 1000 and 2000 pieces.

The stars in Sco-Cen have convergent proper motions of 0.02 to 0.04 arcsec / year. This suggests that the stars move almost parallel to each other at 20 km / s opposite the sun. The speed dispersion of the stars in the subgroups is small 1 to 2 km / s, and the group is not gravitationally bound. Various supernovae have formed over the past 15 million years, leaving a number of expanding gas bubbles around the group, including the Loop-I super-bubble . In 2019, interstellar iron was discovered by Munich researchers in the Antarctic, which was attributed to the local flake, which could have originated near the Sco-Cen Association.

swell

  1. ↑ de Zeeuw, PT, Hoogerwerf, R., de Bruijne, JHJ, Brown, AGA, & Blaauw, A .: A Hipparcos Census of Nearby OB Associations . In: Astronomical Journal . 117, 1999, pp. 354-399. bibcode : 1999AJ .... 117..354D .
  2. ^ Preibisch, T., et al .: Exploring the Full Stellar Population of the Upper Scorpius OB Association . In: Astronomical Journal . 124, August, pp. 404-416. bibcode : 2002AJ .... 124..404P .
  3. ↑ Mamajek, EE, Meyer, MR, Liebert, J .: Post-T Tauri Stars in the Nearest OB Association . In: Astronomical Journal . 124, 2002, pp. 1670-1694. bibcode : 2002AJ .... 124.1670M .
  4. ↑ Madsen, S., et al .: Astrometric radial velocities. III. Hipparcos measurements of nearby star clusters and associations . In: Astronomy & Astrophysics . 381, 2002, pp. 446-463. bibcode : 2002A & A ... 381..446M .
  5. ↑ de Geus, EJ: Interaction of Stars and Interstellar Matter in Scorpio Centaurus . In: Astronomy & Astrophysics . 262, 1992, pp. 258-270. bibcode : 1992A & A ... 262..258D .
  6. ↑ D. Koll, al. et .: Interstellar 60 Fe in Antarctica . In: Physical Review Letters . 123, August 12, 2019. doi : 10.1103 / PhysRevLett.123.072701 .