Before you could read, you probably loved looking at picture books. But what if you couldn’t see? 3D books include touchable objects instead of colorful pictures. But 3D versions of books aren’t always available. Tom Yeh of the University of Colorado Boulder and his team want to make it easy for parents to print 3D books for blind or visually impaired kids. “Ideally a parent could choose a book, take a picture of a page, send the picture to a 3D printer, which would result in a 3D tactile book,” says Yeh. His team has printed Goodnight, Moon by Margaret Wise Brown and Harold and the Purple Crayon by Crockett Johnson, among other classic stories.

After a 10-year journey, the Rosetta spacecraft reached 67P/Churyumov-Gerasimenko, and became the first craft to orbit a comet. Comets may have brought water or even the ingredients for life to planet Earth. The European Space Agency, which is running the mission, hopes to discover more about the composition and life cycle of comets.

The next big milestone was landing a probe on the comet. The touchdown wasn’t perfect—two harpoons intended as fasteners misfired, for example. But scientists on Earth cheered the lander and look forward to its discoveries.

. . . if you’re a lab rat, that is!

How does a rat feel when a male researcher walks into the room? Stressed! Jeffrey Mogil and his team at McGill University in Montreal, Canada, showed in a recent study that a man’s scent freaks out rats; the smell causes a spike in the stress hormone corticosterone. The smell of a male guinea pig, cat, or dog produces the same effect. What about females? No big deal. In fact, if a rat smells a man and woman together, the effect isn’t as strong.

Mogil suspects that this response helped protect rats in the wild. “If you smell a solitary male nearby, chances are he’s hunting or defending his territory.”

Mogil suspects that this response helped protect rats in the wild. “If you smell a solitary male nearby, chances are he’s hunting or defending his territory.”

The International Union for Conservation of Nature now lists all eight pangolin species as endangered or vulnerable to extinction. Go to savepangolins.org to learn more.

A regular printer needs ink, and a 3D printer needs spools of plastic string. But that plastic can cost $30 or more per spool. Plus, making new plastic uses up natural resources. Joshua Pearce of Michigan Technological University knew that there had to be a better way. Why not recycle plastic from around the house?

Pearce and his team built RecycleBot, a machine that melts milk jugs and spits out long plastic strings that you can feed into a 3D printer. All you have to do is clean and cut up the milk jugs first. Pearce’s team calculated that the process uses 90 percent less energy than it takes to produce new plastic. Plus, one recycled spool costs just 10 cents—way cheaper than $30!

RecycleBot’s design is available for free: www.thingiverse.com/thing:12948