Galaxies

Tune in to hear about an upcoming vernal equinox! Many civilizations have made vernal equinoxes into special or even sacred days. Learn how the sun is shifting into new constellations, and what most people get wrong.

If someone you know has their head in the stars, here are some last minute gift ideas. Binoculars, which can provide mind-blowing images of the things like the Pleiades, star clusters, Andromeda Galaxy and the Milky Way.

If you REALLY watch the moon — the way the Babylonians did 3,700 years ago — you'll notice that its path keeps changing. We're not talking about super-obvious lunar behavior like its rapid sky movement, or the nightly shift in where it rises and sets. Some years the moon's nightly motion can mimic the sun's daytime path across the sky. Other years the moon never quite ascends as high as the sun. But the most dramatic part of the cycle is the brief three-year period when the moon gets much higher than the sun.

Astronomers have long sought the origin of the universe, and hence ourselves as well. Using our best equipment, we observe that every galaxy cluster is rushing away from us, and from all others. For every extra one million light-years of distance, galaxy clusters recede 13 miles per second faster. When we retrace their paths we see that everything must have been in a single spot 13.8 billion years ago, which was right here. Clearly, the universe originated then and there. This week: The Big Bang!

Venus is now starting an extraordinary cycle. Also called the evening star, it’s not the least bit hard to find. It will spend the next nine months in the west after sunset, slowly growing higher and brighter.

In science, coincidences grab attention. Our sky has just two disks, the sun and the moon, and both appear the same size. That’s what let that amazing total solar eclipse happen this past April. And we have the best north star of the past 26,000 years. Some people think there are no coincidences, that everything is connected. This week: Coincidences.

Do you or any of your friends know the most abundant element in your body is oxygen? Can you name the only major moon that does not circle around its planet’s equator? (That’s our own Moon). Have any idea that the average cloud weighs one million pounds? We’ll give credit to those who showed us the fundamentals.

On Mars, the curiosity rover's methane-sniffing instrument turned up nothing at all — dashing hopes of finding bacteria, which can produce methane. The search was inspired by Martian ancient history — since it was a very different place in the distant past. Hear how we’re still looking for life elsewhere.

With the current Moon a thin crescent that sets before nightfall, we can be thinking about dark skies and the Northern Lights. Of course, it’s the Sun’s activity that controls the aurora, not our calendar, so if a strong solar flare or even more powerful coronal mass ejection blasts tons of the Sun’s charged particles in our direction, we’ll likely get auroras a couple of days later. Tune in to hear about the aurora avalanche!

Hear about the power of a star and how we’re trying to recreate that energy (for no pollution purposes) here on Earth.