<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31443996</termId><termName>heliometers</termName><termType>PT</termType><termNote><![CDATA[ Instruments that were historically used for measuring the diameter of the sun. In later use, heliometers were used to determine the angular distance between stars.  ]]></termNote><termCreatedDate>2026-03-30 20:52:51</termCreatedDate><relation><relationType>UF</relationType><termId>31443997</termId><termName>heliometer</termName><termType>ND</termType></relation><relation><relationType>BT</relationType><termId>31383815</termId><termName>astronomical instruments</termName><termType>PT</termType></relation></term>  </Zthes>