Ortiz-Leon, Gisela N.
Dzib, Sergio A.
Galli, Phillip A. B.
Mioduszewski, Amy J.
Rodriguez, Luis F.
Torres, Rosa M.
Boden, Andrew F.
Evans, II, Neal J.
Tobin, John J.
 Univ Michigan, Dept Astron, 500 Church St, Ann Arbor, MI 48105 - USA
 CALTECH, Div Phys Math & Astron, 1200 East Calif Blvd, Pasadena, CA 91125 - USA
 Evans, Neal J., II, Cerro Tololo Interamer Observ, Casilla 603, La Serena - Chile
 Univ Oklahoma, Homer L Dodge Dept Phys & Astron, 440 W Brooks St, Norman, OK 73019 - USA
 Leiden Observ, POB 9513, NL-2300 RA Leiden - Netherlands
Total Affiliations: 12
SEP 20 2018.
Web of Science Citations:
We derive the distance and structure of the Perseus molecular cloud by combining trigonometric parallaxes from Very Long Baseline Array (VLBA) observations, taken as part of the GOBELINS survey and Gaia Data Release 2. Based on our VLBA astrometry, we obtain a distance of 321 +/- 10 pc for IC 348. This is fully consistent with the mean distance of 320 +/- 26 measured by Gaia. The VLBA observations toward NGC 1333 are insufficient to claim a successful distance measurement to this cluster. Gaia parallaxes, on the other hand, yield a mean distance of 293 +/- 22 pc. Hence, the distance along the line of sight between the eastern and western edges of the cloud is similar to 30 pc, which is significantly smaller than previously inferred. We use Gaia proper motions and published radial velocities to derive the spatial velocities of a selected sample of stars. The average velocity vectors with respect to the LSR are ((u) over bar, (v) over bar, (w) over bar) = (-6.1 +/- 1.6, 6.8 +/- 1.1, -0.9 +/- 1.2) and (-6.4 +/- 1.0, 2.1 +/- 1.4, -2.4 +/- 1.0) km s(-1) for IC. 348 and NGC 1333, respectively. Finally, our analysis of the kinematics of the stars has shown that there is no clear evidence of expansion, contraction, or rotational motions within the clusters. (AU)