| |  Here's what scientists call a time loop. Green shows the short way through a wormhole. Red shows the long way through normal space. Since the travel time on the green path could be very small compared to the red, a wormhole can allow for the possibility of time travel. Image via Panzi/ Wikimedia Commons. | | |
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| Why are stars brighter at this time of year? | | Looking up on December, January and February evenings, the stars seem brighter. Here’s why.
 View larger. | On June, July and August evenings - no matter where you are on Earth - you look toward the galaxy's center as indicated by the red arrows. On December, January and February evenings, you look away from the center, as indicated by the blue arrows. At this time of year, we're looking into our local spiral arm. Read more. | | |
