Some readings I perused over the past couple of weeks.
1) Our picture of habitability on Europa, a top contender for hosting life, is changing. Jupiter's moon Europa has long been a contender for hosting life. But lately some scientists have expressed their doubts. Europa has an ocean beneath a 20 km icy crust. Geologists now think that the sea floor is not active. They simulated conditions which could generate shallow earthquakes leading to fault movement and exhumation of fresh rock. Reaction of sea water and freshly exposed rocks is necessary for chemical reactions that sustain life. Results suggest an inert sea floor. Another study implied no magmatism on Europa. Rising magma brings with it heat and chemicals. But, could these be transient conditions that we have caught? Maybe there is a cyclicity to Europa's energy flow. Some interesting thoughts in this article.
2) China's Moon atlas is the most detailed ever made. The Chinese Academy of Sciences has released a stunning 1:250,000 scale geologic map of the moon. A decade of research has revealed 17 rock types ( I used to think only basalt!), 81 basins, and 12,000 odd craters! Compiled from orbiting satellites and then sharpened using data from the two lander missions.
3) How Punekars fought for their hill, Vetal Tekdi, to save its ecology. My city Pune has a proud tradition of citizen activism. For the past few years citizens have vigorously protested a road planned along a forested hill slope. This hill has been a life saver for thousands of citizens as a recreation spot. It hosts rich biodiversity and is an important groundwater recharge zone. The Pune Municipal Corporation is insisting on building this road, despite their own reports admitting an adverse environmental impact, and pointing to at best a short term marginal improvement in traffic flow. The fight to save the hill goes back a couple of decades. Shobha Surin has done a good job summarizing this long battle in Question of Cities.