A VLBI Resolution of the Pleiades Distance Controversy

TL;DR

This paper uses very long baseline radio interferometry to measure the Pleiades cluster's distance, resolving the longstanding controversy by providing a more accurate measurement that challenges previous Hipparcos results.

Contribution

It presents the most precise and accurate distance measurement to the Pleiades using VLBI, resolving the discrepancy with Hipparcos data.

Findings

Measured distance of 136.2±1.2 pc to Pleiades

Confirms the accuracy of VLBI over Hipparcos

Supports existing models of young stars in Pleiades

Abstract

Because of its proximity and its youth, the Pleiades open cluster of stars has been extensively studied and serves as a cornerstone for our understanding of the physical properties of young stars. This role is called into question by the "Pleiades distance controversy" wherein the cluster distance of 120.2+/-1.5 pc as measured by the optical space astrometry mission Hipparcos is significantly different from the distance of 133.5+/-1.2 pc derived with other techniques. We present an absolute trigonometric parallax distance measurement to the Pleiades cluster that uses very long baseline radio interferometry. This distance of 136.2+/-1.2 pc is the most accurate and precise yet presented for the cluster and is incompatible with the Hipparcos distance determination. Our results cement existing astrophysical models for Pleiades-age stars.