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What are neutrinos?

Neutrinos – which barely exist – just ran off with another Nobel Prize

How to watch a total eclipse of the moon

Are you planning on watching the September 27-28 eclipse outside? Here are some tips.

Why a totally eclipsed moon looks red

If Earth didn’t have an atmosphere, then, when the moon was entirely eclipsed within Earth’s shadow, the moon would would appear dark …

What is a fairy ring?

Have you ever noticed mushrooms growing in a big circle? It’s known as a fairy ring. How does it happen?

evergreen trees conifers

Earth has 3 trillion trees, says study

That’s more than previous estimates. But the number of trees has dropped by 46% since the start of human civilization, says the study.

What is dark energy?

We need dark energy to explain why gravity seems to be driving galaxies in our universe apart instead of pulling them together.

What is the Yellowstone supervolcano?

Beneath Yellowstone National Park lies a volcanic hotspot. The most recent enormous eruption occurred 640,000 years ago. What’s going on now?

Why do volcanoes erupt?

Volcanoes are channels that transfer molten rock from Earth’s crust to the surface. Here’s why eruptions happen.

Sun's path through the zodiac.

Dates of sun’s entry into each zodiac constellation

Dates of sun’s entry into each zodiacal constellation and the corresponding ecliptic longitude (sun’s position in degrees, east of the March equinox point).

What makes Venus the brightest planet?

Venus is bright because it’s nearby, because it’s blanketed in highly reflective clouds and because of its location in orbit with respect to Earth now.