My seniors, with pure curiosity, simply asked nature their questions and waited for nature to answer.
Literal
I [of-の] seniors [topic-は], pure curiosity [object-を] embrace-and one's-own questions [object-を] nature [to-に] pose, nature [subject-が] answers [nominalizer-の-を] waited.
An elevated, almost scientific/philosophical sentence. 先輩 ('senior, older member') in academic contexts means 'elder students/colleagues.' 抱いて ('embracing, holding [in mind]') is figurative, used for emotions or attitudes. 自然に問いかける ('to pose to nature') has に marking the recipient. The nested 自然が答えるのを待つ ('wait for nature to answer') uses the nominalizer の+を+待つ pattern — 'wait for X to happen.' A beautifully compact rendering of the scientific ideal.