Mars once rippled with rivers and ponds billions of years ago, providing a potential habitat for microbial life. It’s commonly believed that Mars’ water evaporated about 3 billion years ago. But new research reveals signs of liquid water on the Red Planet as recently as 2 billion to 2.5 billion years ago. Salt deposits provide the first mineral evidence confirming the presence of liquid water. The discovery raises new questions about how long microbial life could have survived on Mars, if it ever formed at all. On Earth, at least, where there is water, there is life.