Have you ever stumbled around a dark house, straining to see what's in front of you? Or maybe you've camped out in a dark forest, where nighttime navigation without a flashlight was impossible? Our human visual systems are not as well adapted to low light conditions as those of some other species including cats, bats, and owls. Here’s how they do it.
At mid-northern latitudes, the star Arcturus sets about 2 hours after sunset around Halloween. It sets at the same point on the horizon as the summer sun. It's a Halloween ghost of the summer sun and an echo of long summer afternoons. Read more.
It'll be a great evening - with the lovely bright planet near the crescent moon - for halloweening. And be sure to keep watching the waxing moon. By this weekend, it'll be near Saturn. Read more.
This ghostly face, captured by the Hubble Space Telescope on June 19, is actually a collision of 2 galaxies of about equal size, 704 million light-years from Earth. Read more about the image.
