In what order did the planets in our solar system form?
“Are planets in the solar system that are closer to the Sun older than the ones further away?” — Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to form in our solar system. This happened about 4½ billion years ago. Then the planets began to emerge, as …
Twinkling star reveals the secrets of plasma structures in our cosmic neighbourhood
With the most powerful radio telescope in the southern hemisphere, we have observed a twinkling star and discovered an abundance of mysterious plasma structures in our cosmic neighbourhood. The plasma structures we see are variations in density or turbulence, akin to interstellar cyclones stirred up by energetic events in the galaxy. The study, earlier this …
Will the Earth last forever?
“Will the Earth last forever?” — Solomon, age 5, California Everything that has a beginning has an end. But the Earth will last for a very long time, and its end will come billions of years after anyone who is alive here now is gone. Before we talk about the future of our planet, let’s …
When you wish upon a star, is it already dead?
Deep in the Chilean Desert, astronomers witness a skyscape like few others on Earth. Credit: ESO/Luis Calçada/Herbert Zodet When you wish upon a star, Jiminy Cricket told us, your dreams come true. But according to an idea doing the rounds on social media, that may not be the case: According to astronomy, when you wish …
How many stars are there in the Universe?
“Exactly how many stars are in space?” — MeeSong, Brookline Massachusetts Look up at the sky on a clear night, and you’ll see thousands of stars – about 6,000 or so. But that’s only a tiny fraction of all the stars out there. The rest are too far away for us to see them. The …
Why do some planets have moons and others don’t?
“Why do some planets have moons and some don’t?” — Siddharth, age 6, Texas On Earth, you can look up at night and see the Moon shining bright from hundreds of thousands of miles away. But if you went to Venus, that wouldn’t be the case. Not every planet has a moon – so why …
How has the inside of the Earth stayed hot for billions of years?
“How does the inside of the Earth stay boiling hot for billions of years?” — Henry, age 11, Somerville, Massachusetts Our Earth is structured sort of like an onion – it’s one layer after another. Starting from the top down, there’s the crust, which includes the surface you walk on; then farther down, the mantle, …
Is Mars really as red as people say it is?
“Is Mars really as red as people say it is?” — Jasmine, age 14, Everson, Washington People from cultures across the world have been looking at Mars since ancient times. Because it appears reddish, it has often been called the red planet. The English name for the planet comes from the Romans, who named it …
Have we made an object that could travel 1% the speed of light?
This article is republished from The Conversation under a Creative Commons license.
How high could I jump on the Moon?
“How high could I jump on the Moon?” — Miles, age 5, London, United Kingdom If you were lucky enough to go to the Moon, you’d be able to jump six times as high there as you can here on Earth. Try it: jump up and imagine you’re on the Moon. Six times further up …