Question: What planetary system is a companion of Proxima Centauri b?
Paraphrase: What planetary machine is a companion of Proxima Centauri b?
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q26692445 wdt:P397 ?X . ?X wdt:P399 ?answer}
Answer: Alpha Centauri B, Alpha Centauri A