Gilsemans is most noted for joining the explorer Abel Tasman on his expedition in 1642-43 during which Tasmania, New Zealand and several Pacific Islands were discovered.
Gilsemans yang paling terkenal karena bergabung dengan explorer Abel Tasman pada ekspedisinya pada 1642-1643 di mana Tasmania, Selandia Baru dan beberapa Kepulauan Pasifik ditemukan.