What's the latest in regard to US forex

In the latest forex news we can see that the US dollar fell to a 4-year low against the euro after Moody’s corporation, a major credit rating analyst, warned that the country’s Aaa rating may be downgraded if the ratio of national debt to GDP is not improved. This coincided with Germany’s Federal Constitutional Court decision to make a ruling on Wednesday as to the legality of the eurozone bailout and budget rules, bolstering the value euro. These two news stories saw the euro to dollar rate rally upward. It is believed the US Federal Reserve begin a meeting on Wednesday, with the predicted outcome being the buying of government bonds support the economy and nullify the exchange rate affects.