SCIUTTO: There's growing concern among U.S. officials that North Korea could be planning an unprecedented missile launch with the potential of reaching the United States. Our Barbara Starr at the Pentagon. Barbara, a missile with a capability we haven't seen before?</s>BARBARA STARR, CNN PENTAGON CORRESPONDENT: Jim, what U.S. officials are so concerned about, they are seeing signs, not actually happened yet, but signs that North Korea is preparing for the first time to potentially test fire a mobile missile potentially capable of hitting Guam, Alaska, and parts of the Pacific Northwest. There are three versions of this missile. They see some preparations being made. They don't really know what North Korea's up to. Here's the part that is so concerning to the U.S. This would be the first time a mobile missile has been launched with these extended ranges. The problems for the U.S. is mobile missile launches are very difficult to detect. They come off of trucks, large wheeled vehicles. They can shoot and move very rapidly in wartime. That would mean the North Koreans could make a lot of efforts to evade U.S. surveillance. Very difficult for U.S. satellites to keep track of these mobile launchers. Now, U.S. officials are saying they're not entirely sure what North Korea's up to. North Korea knows the U.S. is already watching overhead. This could be a deception campaign. They could just be moving a lot of things around knowing it will upset the U.S. But, in fact, what they do see are some signs that they are preparing for this type of unprecedented missile launch. The question now is whether Pyongyang will really go ahead with it -- Jim?</s>SCIUTTO: Steady progress on missiles and nuclear devices. Barbara Starr, at the Pentagon. Coming up next, the pay gap between men and women could be getting smaller but a new estimate predicts women will not be paid equally until the year 2059, not if current trends continue. We'll tell you how the White House is trying to buck that trend.
Concerns Over North Korean Missile Launch