On the Nature of the Purported Common Proper Motion Companions to the Exoplanet Host Star 51 Peg

TL;DR

This study investigates purported common proper motion companions to star 51 Peg, finding that these stars are likely unrelated background objects due to inconsistent color-magnitude data despite similar proper motions.

Contribution

The paper critically examines previous claims of companions to 51 Peg and demonstrates that these stars are probably not physically associated, clarifying the nature of nearby high proper motion stars.

Findings

The three candidate stars are likely background objects.

Proper motions alone are insufficient to confirm companionship.

Color-magnitude analysis contradicts the companionship hypothesis.

Abstract

Greaves (2006) proposed that three red, high proper motion stars within 10 degrees of 51 Peg (NLTT 54007, 54064, & 55547) are co-moving companions to this famous exoplanet host star. While the stars clearly have proper motions similar to 51 Peg, the inferred kinematic parallaxes for these stars produce extremely inconsistent color-magnitude positions 2 to 4 magnitudes below the main sequence. All three stars are likely to be background stars unrelated to 51 Peg.