This follows the practice established in the USSR where cosmonauts were usually awarded the title Hero of the Soviet Union.
ðɪs fˈɑːloʊz ðə pɹˈæktɪs ɪstˈæblɪʃt ɪnðə jˌuːˌɛsˌɛsˈɑːɹ wˌɛɹ kˈɑːzmənˌɔːts wɜː jˈuːʒuːəli ɐwˈɔːɹdᵻd ðə tˈaɪɾəl hˈiəɹoʊ ʌvðə sˈoʊviət jˈuːniən.