NEW YORK— Moodys Investors Service has cut MGM Mirages credit ratings to “junk” status. Moody’s said the September terrorist attacks have hurt the Las Vegas-based company, whose 18 casinos include the MGM Grand, Mirage, and Bellagio. It also said MGM Mirages balance sheets “may not improve significantly for some period of time” because of the companys exposure to Las Vegas. Moodys cut MGM Mirages long-term ratings to “Ba1,” its highest “junk” grade, from “Baa3,” and its short-term ratings to “Not Prime” from “Prime-3.” It said the downgrades affect $7.8 billion of debt, and that its outlook is stable. Downgrades to junk ordinarily raise borrowing costs and can force investors not permitted to own junk bonds to sell. Moodys cut at least 60 companies last year to “junk” status from “investment-grade.” These companies are known as “fallen angels.” MGM Mirage was created last year when MGM Grand took over the publicly traded Mirage hotel-casino firm which was founded by Steve Wynn. Reuters