v$temp_space_header and dba_temp_free_space providing different data

Guys,

SQL> select * from v$temp_space_header

TABLESPACE_NAME                                                 FILE_ID BYTES_USED BLOCKS_USED BYTES_FREE BLOCKS_FREE RELATIVE_FNO

------------------------------------------------------------ ---------- ---------- ----------- ---------- ----------- ------------

TEMP1                                                                 1 3.4359E+10     4194176          0           0            1

TEMP2                                                                 2    1048576         128 3220176896      393088            1

SQL> sselect

SQL> select * from dba_temp_free_space;

TABLESPACE_NAME                                              TABLESPACE_SIZE ALLOCATED_SPACE FREE_SPACE

------------------------------------------------------------ --------------- --------------- ----------

TEMP1                                                             3.4359E+10      3.4359E+10 2.7746E+10

TEMP2                                                             3221225472         1048576 3220176896

Why there is so much difference between output from both views