American Scientist

A decade ago, the robotic spacecraft Cassini had already become a huge success. It had released its Huygens probe onto Saturn’s moon Titan, and it was returning spectacular imagery of the giant planet itself, as well as its other moons. At that time, we asked Carolyn Porco, leader of the imaging team for the Cassini-Huygens mission and director of the Cassini Imaging Central Laboratory for Operations, to fill in American Scientist readers on the mission results so far. Her resulting essay in the July–August 2007 issue showcased the early results from the first 1,000 days of the mission.

In this issue, we are returning to Cassini as its mission recently came to a preplanned end. To preclude Cassini from crashing into one of Saturn’s moons as it ran out of propellant and potentially spreading terrestrial contamination there, the spacecraft was instead deliberately plunged into Saturn. But before its final encounter with the planet, Cassini spent much of the final year of its mission taking a detailed look at Saturn’s rings. As Matthew S. Tiscareno explains in “Cassini and the Rings of Saturn," this concluding year has been practically a whole new mission for the spacecraft, with some spectacular results.

Space exploration uses remarkable technology, but the devices we use daily are also pretty amazing, even if we’re not paying attention to how they work. This issue tackles from multiple angles topics related to technology and how it affects us. In our cover story, Alexis Webb and Erik Herzog look at the role that late-night viewing of backlit devices, such as cell phones and tablets, is having on our biological clocks, and our health, as a result. In “Adapting Your Body Clock to a 24-Hour Society," the authors look at research that might help reset our biological clocks to be more in tune with our modern style of living.

Mobile devices offer us the convenience of information at our fingertips, but are they also a conduit for making us more susceptible to falsehoods? In “The Persistence and Peril of Misinformation,” Brian G. Southwell, Emily A. Thorson, and Laura Sheble review what is known about how people evaluate information and discuss how knowledge of these processes could be used to battle hoaxes and fake news.

Two articles in this issue discuss machine learning and its supporting algorithms, which are increasingly framing our lives whether we are aware of it or not. In the Spotlight section, Simson L. Garfinkel reports on a recent panel discussing proprietary algorithms and who should have access to how they work. Garfinkel points out that these types of algorithms not only can control what music you hear or what news you see on social media, but also are increasingly used to screen which job applicants to interview or determine how long a jail sentence should be—and there is currently little recourse for those affected to dispute the results from the software.

One specific use of machine-learning algorithms is what’s called predictive policing, where law enforcement agencies use software to help determine everything from where officers patrol to which members of the public might be more likely to be a victim of a crime. In the Scientists’ Nightstand section, an excerpt of Andrew Guthrie Ferguson’s latest book, The Rise of Big Data Policing, digs into such programs, and why efforts in New Orleans were successful when similar programs in other cities didn’t have such dramatic results.

As Garfinkel points out, going back to a world where nothing is filtered isn’t really an option; we would all end up buried in spam and cat videos. Science is helping society find the balance between technology that is useful and applications that, maybe, step too far for human comfort.—Fenella Saunders (@FenellaSaunders)