Depends on the consistency of the data - assuming a single space is the separator between what you want to appear in column one vs two:
SELECT SUBSTR(t.column_one, 1, INSTR(t.column_one, ' ')-1) AS col_one,
SUBSTR(t.column_one, INSTR(t.column_one, ' ')+1) AS col_two
FROM YOUR_TABLE t
Oracle 10g+ has regex support, allowing more flexibility depending on the situation you need to solve. It also has a regex substring method...
Reference: