* Strong U.S. earnings lift sentiment, equities * Spain retains investment-grade debt rating * Dlr index hits 1-mth low * Euro rises to 1-mth highs on dlr, yen * Coming Up: U.S. Sep. housing starts; 1230 GMT (Updates prices; adds quotes, details) By Carrie Ho SHANGHAI, Oct 17 (Reuters) - London copper extended gains into a second session on Wednesday on a weaker dollar, strong U.S. earnings reports as well as Moody's Investors Service's affirmation of Spain's investment grade rating. Asian shares rose on strong earnings reports from some big-name U.S. companies, while the euro rose to a one-month high against the dollar after Moody's Investor Service kept Madrid's sovereign rating at investment grade Baa3, thereby easing some fears over the euro zone economy. The euro's strength pushed the dollar index down to a one-month low, making dollar-denominated commodities like London copper cheaper for holders of other currencies. Also helping to support base metals prices was a report by Kyodo News that Japanese Prime Minister Yoshihiko Noda plans a new round of economic stimulus by the end of next month as the country has entered a lull. The report quoted sources close to the prime minister. "London copper prices have been nudged up by some positive news today, such as Spain's unchanged rating and good U.S. earnings reports. But until we get compelling evidence that the global economy is lifting or that governments are introducing fresh stimulus measures, gains will be limited," said a Shanghai-based trader. Three-month copper on the London Metal Exchange had risen 0.2 percent to $8,139.75 per tonne as of 0701 GMT, after rising 0.4 percent on Tuesday. The most active January copper contract on the Shanghai Futures Exchange, however, edged down 0.2 percent to close at 58,660 yuan ($9,400) per tonne. "Shanghai base metals have resisted rising as today's positive news is not that significant. Also, there has been a feeling of uncertainty in China ahead of GDP figures tomorrow and the 18th Communist Party Congress, which made investors more inclined to sell today," the trader added. Economists polled by Reuters indicated China's annual economic growth probably slowed for a seventh straight quarter in the July-September period to expand 7.4 percent, down from 7.6 percent in the second quarter and the weakest level since the depths of the global financial crisis. "We see copper ranging between $8,000-$8,400 in London and 57,500-60,000 yuan in Shanghai," said a Shanghai-based trader with an international firm. In the physical markets, traders said spot copper demand was still lacklustre, with the day's spot-to-front-month discount doubling from Tuesday to as high as 200 yuan. Putting a cap on copper gains were fears over the health of the world's economy, with the U.S. economy still under pressure from abroad in September as weak global demand appeared to hold back factory output and a rise in gasoline prices dented consumers' spending power, data showed on Tuesday. Other data showed only mild underlying inflation pressures in the world's largest economy, potentially giving the Federal Reserve room to keep interest rates low to boost the economy. In industry news, BHP, the world's No.2 copper producer, said copper production in the quarter rose 24 percent from a year ago, with its majority-owned Escondida mine in Chile headed for a 20 percent production increase in fiscal 2013. Aurubis, Europe's biggest copper smelter, cut its copper products output this year in response to weaker demand, a company executive told Reuters in an interview on Tuesday. Newmont Mining Corp announced on Wednesday preliminary third quarter attributable gold and copper production of 1.24 million ounces, 35 million pounds, respectively. Base metals prices at 0701 GMT Metal Last Change Pct Move YTD pct chg LME Cu 8139.75 14.75 +0.18 7.10 SHFE CU FUT JAN3 58660 -130 -0.22 5.45 LME Alum 1956.00 -1.00 -0.05 -3.17 SHFE AL FUT JAN3 15490 -25 -0.16 -2.21 HG COPPER DEC2 370.65 0.65 +0.18 7.87 LME Zinc 1905.00 7.50 +0.40 3.25 SHFE ZN FUT JAN3 15120 -75 -0.49 2.20 LME Nickel 16896.00 -34.00 -0.20 -9.70 LME Lead 2121.00 7.50 +0.35 4.23 SHFE PB FUT 15665 -75 -0.48 2.45 LME Tin 21350.00 -150.00 -0.70 11.20 LME/Shanghai arb 894 Shanghai and COMEX contracts show most active months ^ LME 3-m copper in yuan, including 17 pct VAT, minus SHFE third month

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