"Not magical, as far as we know," Steve answers, but the 'how' really isn't his area of expertise, and the 'why', nobody can actually ascertain. "But we have no idea what it's for, or why we're here." Since she doesn't seem too shellshocked, he even gives her the whole truth. "The welcome announcement you saw in quarantine, that's all we have. Sometimes we're given missions. Sometimes our lives are put in danger. We can never predict what's coming next - and we've been trying."