The stock market stayed on an upward trajectory on Tuesday, bolstered by strong earnings reports and the sense that corporate America is still enjoying the same favorable conditions that have helped boost its prospects throughout the past five years. Even though the broader market's gains were quite respectable, with major averages rising around half a percent, Sprint (NYSE:S), MGM Resorts (NYSE:MGM), and Orbital Sciences (NYSE:OA) gave shareholders much more impressive returns on their shares today.

Source: Sprint.

Sprint gained 11% as the wireless-telecom network operator reported its first-quarter results. Sprint said its first-quarter loss narrowed by almost three-fourths, as revenue climbed 0.9%. The company boasted a substantial 3.5% drop in operating expenses, tied to cost-cutting efforts to try to maximize its profitability. Even though Sprint lost 750,000 postpaid phone customers during the quarter, it added more than 500,000 tablet users, and investors were pleased to learn that Sprint's extensive work to improve its network quality should be done soon. Once those upgrades are in place, Sprint expects its customer counts to start rising again, along with revenue-per-user metrics. According to Sprint, the company's efforts to sign up new customers using its extended-family "Framily" plan have been successful in drawing more than a million new signups. As Sprint and its peers move away from subsidies, it'll be interesting to see how network quality moves to the forefront in how customers select wireless providers.

MGM Resorts picked up 9% after strong results in the Asian gaming capital of Macau as well as a surprisingly good performance in Las Vegas helped boost its overall first-quarter results. Revenue climbed 12%, and earnings per share more than doubled expectations. MGM's China segment saw sales jump 26%, reflecting the continued outperformance of Macau, but MGM's Vegas Strip properties also saw favorable moves in occupancy rates, with revenue per available room soaring 14% to $135. With MGM Resorts expecting to open its property on Macau's red-hot Cotai Strip within the next two years, its growth could soar as long as the Asian economy stays on course through 2016.

Source: Orbital Sciences.

Orbital Sciences soared 17% after Alliant Techsystems (NYSE: ATK) announced a two-part transaction that will result in Alliant's aerospace and defense business buying out Orbital Sciences in a merger. Alliant Techsystems will first spin off its outdoor-sports related commercial gun and ammunition business to its own shareholders, and then Orbital Sciences shareholders will get 44.9 shares of Alliant Techsystems stock for every 100 shares of Orbital Sciences stock they own. The move should help both companies gain a bigger foothold in the defense business while also freeing the gun business to fend for itself and take advantage of its own opportunities.