Showing posts with label Jupiter. Show all posts
Showing posts with label Jupiter. Show all posts

26 March 2013

How much water really is there on Spaceship Earth?

We're told that all the water on Earth came here via comet impacts. That's a fact that's pretty hard to reconcile. I mean there's just so much water right?

Not when you look at it all balled up and sitting next to the planet...

And not when you compare it against all the liquid water in Saturn's moon Titan - not even compared to the water on Jupiter's moon Europa.

The heavy bombardment period must have been a pretty serious time to be around...



7 March 2013

Oh my. This puts it all in perspective wonderfully...

So just how big is the Sun?

Pretty hard to go by this gorgeous picture for summing it up in one:



Yes—those little specs right over on the left side are the four terrestrial planets.

It was done by Bob Riddle, and he has a bunch of related information over on his blog.

Via Brad Snowder (@skywise88).
On the topic of comparisons, did you know that the mass of Jupiter is some 2.4 times the combined mass of every other thing in our Solar System—excluding the Sun. Every planet, moon, ring, asteroid and dust mote. But even that pales next to the Sun. But wait: even the Sun pales next to the size of red super giant Betelguese, which is in our skies at present, in the Orion constellation. If Betelguese was where our Sun is, its surface would be right out past Jupiter's orbit (which is 5.2 Au, or 5.2 times the distance from Earth to the Sun, or 816,520,800 kilometres). Betelguese's radius varies between 950 and 1200 million kilometres. Now that's big...