Just like people, planets are born and they die. We know how people die. But google “how planets die” and you’ll get the wrong answer. … More How planets die
Can moons orbit moons? wondered Juna and I.
Some planets have moons, you know, up in the sky
But none of those moons has its own moon around it.
When Juna’s son learned this he just was astounded! … More Can moons orbit moons? — the poem
Planets orbit stars. Moons orbit planets. But no moons have their own moons (let’s call them submoons). Why is that? … More Can moons have moons?
One fine week in May, well, I needed some peace
I packed up my bags and I headed to Nice… … More The MOJO videos
Mars is a weirdo. (Well, as far as planets go). Why is it so small (just 11% as massive as Earth)? … More Mars’ growth stunted!
I once ordered a beer then straight away spilled it all over the bar. There was just a tiny sip left in the glass. Frowny face.
Remember ‘Oumuamua, the weird-shaped rock flying through the Solar System? Just like my sip of beer, it might only be a small piece of what it once was. … More ‘Oumuamua: a shred of its former self
Gas giants are the bullies of planetary systems. They are hundreds of times more massive than small rocky or icy worlds, so when gas giants throw a tantrum, their whole planetary system feels it. Giant planet moons are among the innocent bystanders swept up in the chaos. Giant planets around other stars have different orbits … More Exo-moons: Innocent bystanders during gas giant instabilities
In Rendezvous with Rama (by Arthur C. Clarke), a mysterious object is discovered passing through the Solar System. The object has a strange shape — it’s a giant cylinder. It was discovered by the Spaceguard survey, designed to find objects that might impact Earth (so-called near-Earth objects). Spoiler alert: the cylinder is a spaceship sent … More A cigar from another star
The asteroids may be cosmic refugees, ejected from their homes to wander the Solar System, eventually settling in the asteroid belt. … More The asteroid belt: a cosmic refugee camp?
Imagine a dry Earth. No waterfalls. No oceans. No beer (or people to drink it). A sad place. Water is pretty important stuff. In this post we will go deep into how Earth got its water (much deeper than in this post from a while back). And since it’s connected with how Earth formed, our … More Where did Earth’s (and the asteroid belt’s) water come from?