Since April 2019, a fridge-size instrument attached to the International Space Station (ISS) has tickled the treetops of much of the planet with laser light, mapping forests’ carbon stores and the wildlife habitat they provide. Yet in early 2023, the laser is set to be jettisoned into Earth’s atmosphere, where it will burn up unless NASA approves a plan to extend its tenure. Researchers and some U.S. Congress members are now lobbying NASA to give the Global Ecosystem Dynamics Investigation (GEDI) instrument a second life so it can finish measuring the world’s tropical and temperate forests. …A NASA spokesperson noted that GEDI is one of seven Earth-observing instruments on the ISS, three of which are being considered for extensions. He said the NASA review of GEDI, set for next month, will consider the costs and benefits of extending the mission, which would involve “multiple complex operations.”