U.S. stocks edged higher at the open Tuesday after better-than-expected results from Alcoa Inc. (NYSE:AA) helped lift investor sentiment over the start of second-quarter earnings season. 

Alcoa rose after the aluminum maker posted earnings and revenue that topped Wall Street expectations, while Intuitive Surgical fell after the company said it expects second-quarter revenue below analysts' forecasts.

Later this week, JP Morgan Chase & Co. (NASDAQ: JPM) and Wells Fargo & Co. (NYSE: WFC) are scheduled to report earnings.

On the economic calendar, small business optimism slipped in June from its one-year high after uncertainty over the economic recovery. The Treasury is schedule to auction $32 billion in three-year notes with the results available after 1p.m. Eastern.

As of 10:02 Eastern, the Dow Jones industrial average .DJI gained 70.58 points, or 0.46 percent, to 15,295.27. The S&P 500 Index .SPX added 8.42 points, or 0.51 percent, to 1,648.88. The Nasdaq Composite Index .IXIC rose 8.36 points, or 0.24 percent, to 3,493.19.