The Hipparcos parallax for Polaris

TL;DR

This paper confirms that the Hipparcos parallax measurement for Polaris is accurate and rules out the possibility of a significantly larger parallax based on detailed data analysis and other observational evidence.

Contribution

It provides a thorough re-evaluation of Hipparcos data and other observations, conclusively supporting the original parallax measurement for Polaris.

Findings

Hipparcos parallax for Polaris is robust

No observational evidence supports a larger parallax

The claim of a 2.5 mas discrepancy is refuted

Abstract

This letter follows a recent claim that the Hipparcos parallax for Polaris could be too small by 2.5 mas. It examines in detail the Hipparcos epoch astrometric data for Polaris, as well as the viability of other observations that were put forward to support a larger parallax. The Hipparcos determination of the Polaris parallax is shown to be sufficiently robust to fully exclude a significantly larger parallax, and there is no observational support from other observations, such as a supposed presence of a cluster, either.