sql server 2008 - How to get union of two tables with different alias -

i want union want show 1 column twice different alias. e.g

select first table1  union  select second table1 

it shows first output.

but want show both first , second. how can achieved in mssql?

union combines results 2 queries 1 set of columns. there's no way make column name change halfway down. closest can think of

select first , null second  table1   union   select null first , second  table1