Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-09-04
Astronomy and Astrophysics
Astrophysics
to appear in Jan 2008 AN (5 pages), note added in proof regarding new distance estimate (131+-3 pc) using revised Hipparcos pa
Scientific paper
10.1002/asna.200710827
The Ophiuchus molecular cloud complex has produced in Lynds 1688 the richest known embedded cluster within ~300 pc of the Sun. Unfortunately, distance estimates to the Oph complex vary by nearly ~40% (~120-165 pc). Here I calculate a new independent distance estimate of 135 +- 8 pc to this benchmark star-forming region based on Hipparcos trigonometric parallaxes to stars illuminating reflection nebulosity in close proximity to Lynds 1688. Combining this value with recent distance estimates from reddening studies suggests a consensus distance of 139 +- 6 pc (4% error), situating it within ~11 pc of the centroid of the ~5 Myr old Upper Sco OB subgroup of Sco OB2 (145 pc). The velocity vectors for Oph and Upper Sco are statistically indistinguishable within ~1 km/s in each vector component. Both Oph and Upper Sco have negligible motion (<1 km/s) in the Galactic vertical direction with respect to the Local Standard of Rest, which is inconsistent with the young stellar groups having formed via the high velocity cloud impact scenario.
No associations
LandOfFree
On the Distance to the Ophiuchus Star-Forming Region does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with On the Distance to the Ophiuchus Star-Forming Region, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the Distance to the Ophiuchus Star-Forming Region will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-415068