The first of two rovers landed safely on Mars Saturday night and sent back screenfuls of black-and-white images from Gusev Crater, marking a successful start to NASA’s first exploration of the Red Planet’s surface in more than six years. Controllers at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., whooped, clapped and hugged each other shortly before 9 p.m. PT (midnight ET) when they heard that a carrier tone was received from the Spirit rover. That signal, relayed by NASA’s orbiting Mars Global Surveyor, confirmed that the spacecraft had landed intact and right side up.