Long-time advocate of SLS rocket says it’s time to find an “off-ramp”
Maybe NASA’s SLS should be cancelled – but not by Elon Musk
SLS could launch a Titan balloon mission | Boeing engineers proposed a design akin to a "traditional blimp" filled with helium and two ballast tanks, equipped with RADAR/LIDAR systems and atmospheric sensors. The team expects such a balloon to last in Titan's atmosphere for years.