With growing support from the federal government, scientists are accelerating their hunt for life beyond Earth. They also are broadening the search to include organisms unlike any of those on our home planet — what some researchers call “weird life.” By this, they mean alien forms of life that are not based on our familiar DNA but on a different genetic code. In theory, creatures made of unusual biological or chemical structures might exist on moons or planets that lack liquid water, a must for life as we know it.