Data from the Mars InSight lander points to the presence of liquid water underneath its crust. Also, some national and state parks are changing the way they open up campsite reservations online to make them more accessible to everyone.Scientists Find Strong Evidence For Liquid Water On MarsScientists discovered that there could be oceans’ worth of liquid water hidden underneath Mars’ surface. More than 3 billion years ago, Mars had lakes, rivers, and maybe even oceans on its surface. It was very different from the arid red planet we know today.But the question remains—when Mars’ atmosphere changed, where did all that water go? This discovery could offer up new clues and possibly spur on the search for life on Mars.Ira talks with Maggie Koerth, science writer and editorial lead for Carbon Plan, about this discovery and other science news of the week, including why the WHO declared mpox a global health emergency, the microbiome of your microwave, a green-boned dinosaur named Gnatalie, and how love is in the air for brown tarantulas.Releasing Campsite Reservations In Waves Makes Booking FairerBack in 2022, Science Friday discussed how campsites in state and national parks were virtually impossible to reserve, unless you had a lot of time on your hands and knew exactly when those reservations were going online. Research had shown that the people able to reserve these sites were often wealthy, educated, and white, leaving lots of other people out of the fun of camping.But two years later, the same team that found those results says there’s good news: Many state and federal campgrounds have changed how their booking windows work, and as a result, camping has become more equitable.For example, Saddlehorn Campground near Grand Junction, Colorado, was identified as a campground with an inequitable reservation system in a 2022 study. After its publication, campground managers reached out to the study authors to see how they could do better.“They’ve created what I would call the gold standard in an equitable recreation rationing spectrum for these campsites,” said Dr. Will Rice, assistant professor of outdoor recreation and wildland management at the University of Montana in Missoula.This method is to release campsites in waves: Some become available six months in advance, some two weeks in advance, and some day-of. This allows more flexibility for people to book, and is an easy fix on the part of the campgrounds.Rice joins Ira Flatow to talk about these advancements. Since his first appearance on Science Friday, Rice has testified before Congress about the importance of camping reservation equity, and has helped both federal and state campgrounds change their booking reservation windows.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.