It has long been a sport for skywatchers to spot the youngest possible crescent moon after sunset, with the eye alone. What does it take to see a very young moon? Details here.
Can you hear a meteor as it streaks overhead? Some people have reported hearing meteors with a sizzling sound like bacon frying. Scientists now say you can, and explain how it happens.
The Brocken Spectre is your own shadow, cast on mists below you, when you are mountain climbing. The shadow may appear enormous and has a ring around it.
The major planets in our solar system orbit, more or less, in a single plane. That’s why you can look for them along the same sky path traveled by the sun and moon. Is the same true for exoplanets in distant solar systems?
Uranus lies nearly sideways with respect to the plane of its orbit around the sun. That sideways tilt makes a huge difference between winter-summer on Uranus, and autumn-spring.
One journey of our sun and planets around the center of our Milky Way galaxy is sometimes called a cosmic year. That’s approximately 225-250 million Earth-years.
First time we can see 5 planets at once since 2005. All 5 are up before dawn, still, and all 5 will remain visible until Mercury disappears in the dawn just after mid-February.
Jupiter’s gravity slings long-period comets out of harm’s way, while nudging some asteroids closer to Earth. And, in 1770, Jupiter took aim on Earth – but missed.