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This Week's Amazing Sky
The Big Dipper is an old friend to most of us. Poetically, it is spring itself, the season of renewal. Just go outside in early evening, and you’ll see stars shaped in a dipper pattern high in the northeastern sky.Looming large in the night sky, the Big Dipper’s shape is mutating and will appear different in just a few thousand years, but it hasn’t changed a bit since we were kids.What…
Let’s do something different, and mix sky-stuff with weird science! Ready? Here are seven strange science facts—about everything under the Sun from rainbows to our reflection in mirrors!
Number 1. A rainbow has no independent reality. Sunlight and raindrops are not enough to create one. An observer is necessary for its existence, by standing exactly where the 42-degree refraction…
We’ve long had a fascination with going to Mars. The manned trip back to the Moon in late 2024 is the first step in getting humans to the Red Planet. But as planning for manned visits to Mars continues, researchers keep studying risk. Interestingly, it may not be technology that limits our exploration, but our own human physiology.When Will Humans Go to Mars?Since the 1960s,…
The Sun is setting earlier and earlier: It’s really dark. The leaves are dropping quickly now, so barren branches now tremble in the wind. And yes, even that wind is generally stronger during the cold months.
Gather round the campfire. It’s the perfect time to tell blood curdling tales of the sky’s sinister side. Ramping up the scare-factor is that backyard sky-gazers are usually…
Would you like to find not one, but two black holes? You’ve come to the right place. That place is your own backyard. All you have to do is look up at around 7:30 p.m. any time during the next week.
What is a Black Hole?
A black hole in space is an object that has so much material packed into a small region that not even light can escape its gravitational pull! Nothing can…
Sunspots are disappearing more rapidly than usual as the Sun prepares to enter the solar minimum. The last time the absence of sunspots was so prolonged was the “Little Ice Age,” which happened back in the 1600s. Will Earth experience another cold snap?
First, understand that the Sun normally follows sunspot cycles of roughly 11 years. Think of sunspots as storms…
What is the most distant object humans have ever seen in the known Universe? The latest record-holder is a galaxy that is about 13.4 billion light-years away! Or, is it? Something screwy is going on when we talk about distances in an our ever-expanding Universe.
The Universe itself is roughly 13.8 billion years old, so this distant galaxy (MACS0647-D) is indeed…
One of the most frequent topics letter-writers contact us about is meteors. Also known as shooting stars or falling stars, they usually appear as fast streaks across the sky. People gasp when they see them. Although most are rather dim, they are occasionally brilliant and sometimes regarded as UFOs. Many wrong ideas abound. So here’s the true story.
What is a Meteor?
The average…
The air you breathe is made up of lots of other things besides oxygen! So, what is air made of? Let’s find out with Bob Berman, who always adds a breath of fresh air to any topic.When we look up into the sky, we’re looking through dozens of miles of transparent gases, which we breathe from birth to death. Do you know the three gases you’re breathing in right…
We’ve grown up with four seasons. But they don’t always match what we experience. What about dividing our season by the strength of the Sun?
Think about it. People who go skiing or snowboarding in mid-December have officially hit the slopes during the autumn. Those who ski in mid-March are doing so during winter. And yet, those March skiers get sunburned six times faster…
The word “infinity” is intriguing, but frustrating. That’s because infinity cannot be visualized. How do you picture it? Let’s explore …
What is Infinity?
Infinity is the idea of something that has no end. Infinity does not “get larger.” Infinity is not a real number. In our world, there is nothing like this. Most things have an end, but infinity is endless. We do not go “to…
Ever heard of a “penumbral eclipse” of the Moon? What is this? Is it an eclipse? Sort of. Let’s get to the question …
What is a Penumbral Eclipse?
To be honest, penumbral lunar eclipses are not that exciting if you’re just looking at the Moon. The Full Moon really doesn’t change its appearance during a penumbral eclipse as it does during a total eclipse of…