NASA has lost contact with one its three spacecraft orbiting Mars, the agency announced Tuesday. Meanwhile, a second Mars orbiter is perilously close to running out of fuel, and the third mission is running well past its warranty.

By Joey Roulette, Ross Kerber and Echo Wang WASHINGTON, Dec 12 (Reuters) - Investors eyeing SpaceX's potential blockbuster IPO may need to brace themselves as CEO Elon Musk balances his risky quest to reach Mars with growing the revenue-rich Starlink satellite broadband business that would offer more reliable shareholder returns.