This paper presents new observations of the planet-hosting , visual binary GJ 86 ( HR 637 ) using the Hubble Space Telescope .
Ultraviolet and optical imaging with WFC3 confirms the stellar companion is a degenerate star and indicates the binary semimajor axis is larger than previous estimates , with a \ga 28 AU .
Optical STIS spectroscopy of the secondary reveals a helium-rich white dwarf with C _ { 2 } absorption bands and T _ { eff } = 8180 K , thus making the binary system rather similar to Procyon .
Based on the 10.8 pc distance , the companion has 0.59 M _ { \odot } and descended from a main-sequence A star of 1.9 M _ { \odot } with an original orbital separation a \ga 14 AU .
If the giant planet is coplanar with the binary , the mass of GJ 86Ab is between 4.4 and 4.7 M _ { Jup } .

The similarity of GJ 86 and Procyon prompted a re-analysis of the white dwarf in the latter system , with the tentative conclusion that Procyon hosts a planetesimal population .
The periastron distance in Procyon is 20 % smaller than in \alpha Cen AB , but the metal-enriched atmosphere of Procyon B indicates that the planet formation process minimally attained 25 km bodies , if not small planets as in \alpha Cen .