Like “lava tubes” found here on Earth, scientists suspect that lunar caves formed when molten lava flowed beneath a field of cooled lava, or a crust formed over a river of lava, leaving a long, hollow tunnel. If the ceiling of a solidified lava tube collapses, it opens a pit, like a skylight, that can … Read more
Mini-SAR is a lightweight (less than 10 kg) imaging radar. It uses the polarization properties of reflected radio waves to characterize surface properties. Mini-SAR sends pulses of radar that are left-circular polarized. Typical planetary surfaces reverse the polarization during the reflection of radio waves, so that normal echoes from Mini-SAR are right circular polarized. The … Read more
Only 2 inches, or 5 centimeters, wide, NASA’s tiny but mighty retroreflector, called a Laser Retroreflector Array, has eight quartz-corner-cube prisms set into a dome-shaped aluminum frame. The device is simple and durable, scientists say, requiring neither power nor maintenance, and can last for decades. Its configuration allows the retroreflector to reflect light coming in … Read more