universe

Two of the five brightest stars, Canopus and Vega, are antipodal to each other on the celestial sphere. So when Vega becomes the north star 12,000 years from now, Canopus will then be the south star. And what a spectacular situation – having a dazzling, zero magnitude luminary marking each of our poles.

Every summer there’s a great meteor shower, the Perseids. Some years they are spectacular, other years you only see a tenth of what’s happening. We’ll hear how visible the shooting stars will be this year.

Pluto stood at opposition last week, meaning it’s now at its brightest of the year.But that's not good enough. It's so dim, even large backyard telescopes show it as a faint speck lost among the zillions of other dots in Sagittarius. At magnitude 14.3, Pluto is 600 times fainter than the dimmest naked-eye stars.

The next clear night at around dinnertime, look high in the north. You’ll see the famous Big Dipper, which you’ve probably recognized since childhood. But now follow the curved arc of the Dipper’s handle, and it points to a very bright orange star, the only brilliant star high in the north – the famous Arcturus. It’s the only celestial body to open a world's fair. And the only major star that will soon ... disappear!

Backyard astronomers are really getting into two-eye observing. Sales of binoviewers and matching eyepieces have exploded in the past five years. This week we’ll examine this 3-D realm in all its dimensionality.

What's the most common thing in the universe? Well, there are more smaller objects than larger ones, more minnows than whales, so think of the least massive particle that envelops us. The Answer is: The neutrino. Created in the core of the Sun, they fly outward in astonishingly thick hordes, passing through everything effortlessly. Each second, six trillion neutrinos fly through your eyes.

Given that July 4th is almost here, many of us are about to be in the middle of a crowd comfortable sprawled on blankets or lawn chairs and all looking up at the sky at the same time. Most communities don’t start the show until nearly full darkness has fallen at around 9:30 or even 10 p.m., which gives us plenty of time to gaze into the deepening twilight. This year, no planets are out then, but there will be a very conspicuous crescent Moon.

We all know the names of the planets. Many people can even recite them in their correct order from the Sun. But actually seeing them in a line – well, that’s something special. And this month we’ll explain how and when that’s happening.

The Big Bang theory, strongly supported by the cosmic microwave background and the cosmic expansion rate, says that starting 13.8 billion years ago, everything initially raced away from everything else like an inflating balloon.

This week we’ll hear about our galaxy’s five most abundant elements, the remaining seven dozen elements (which together they make up just 4% of the universe) and the unknown dark matter.