Where am I going? As you'll learn in this issue, the way the brain processes the straightforward, location-based meaning of that question is just as interesting as its ability to ruminate on the existential meaning of the phrase. Our brain has a GPS-like system that senses where we are and where we are headed. It also factors in the passage of time in its calculations of position, doing so with an ease that leaves us barely aware of the effort. The processing occurs in networks of cells deep within the brain, which collaborate to create a mental map of our environment. These maps take the form of patterns of electrical activity that fire in a way that echoes the shape of the surrounding layout and our position in it.
Intriguingly, these pathfinding regions of the brain are involved in the making of new memories. Unforgivably, perhaps, my own brain has just suggested to me that this fact puts a new twist on the phrase “a stroll down memory lane.” Nobel Prize–winning neuroscientists May-Britt Moser and Edvard I. Moser explore the terrain further in our cover story, “Where Am I? Where Am I Going?”
Unfortunately, carbon emissions are headed in only one direction—up. With Paris climate talks drawing attention to the problem of excess carbon in the atmosphere from fossil-fuel burning, many have pointed to the need for carbon capture and storage. But can we afford it? In “The Carbon Capture Fallacy,” senior reporter David Biello takes a look at a case in point: the building of the enormous Kemper “clean coal” power plant in Mississippi, which is intended to generate energy from the dirtiest form of coal while siphoning off the emissions. The captured carbon dioxide would, in turn, be pumped into oil wells to force out more oil. Kemper is turning out to be expensive—and costs have led to the shutdowns of more than a couple of dozen such plants. Can we find a way forward?
Shifting our focus to other worlds, we can soar through the magazine to the article “Rings of a Super Saturn,” by astronomer Matthew Kenworthy. Think of Saturn, our solar system's second-largest planet—nearly 10 times the width of Earth—and its graceful rings. Now try to imagine what astronomers have found: a ring system some 200 times larger, around a giant planet orbiting a distant star in our Milky Way galaxy. This exoplanet may even have the first moon detected outside our solar system. These and other wonders await in this month's edition.