Scale of all orbits in our solar system.

Scale

In the dead center lies the Sun, to scale. Every planetary orbit is a different color, though it gets hard to see the orbits of Mercury and Venus because they are so small compared to the actual size of our system. Mars orbit lies on the outside of the red circle and the asteroid belt lies within the grey area. Beyond that, on the outer edge of the next circle is Jupiter’s orbit. Saturn’s orbit takes it almost twice as far from the Sun. Twice as far as Saturn is Uranus and then, on the farthest edge of the outer, green circle lies Neptune.

This is only the scale of all of our planet’s orbits. Our solar system is multiple times larger. At least a light year or two.

If you zoom in to the center, you’ll see a white speck (the Sun). This represents how big the Sun actually is when viewed from above (and compared to the orbits). The Sun, while it is a huge 700,000 miles wide, is really quite small in the grand scheme of things. When it begins running out of fuel, it will expand (I know, counter-intuitive) into a red giant. At this point it will possibly become big enough to swallow Earth and reach the outer orbit of Mars.

Comet 67P/Churyumov-Gerasimenko – Surprise! Contact binary.

Rosetta_67PCG_14July_2014

So Rosetta is landing on this comet soon. As it got closer there was talk that the comet may be two-fee, two comets orbiting a barycenter. That is probably what it was at one point in time, however now it is a contact binary. These two nuclei began fusing somewhat recently into what now looks like a rotating rubber ducky without a beak. Go, go, go!