Astr4: Giants

Front 1

What did Gary Flandro discover?

Back 1

Flandro discovered that during the late 1970's, the four Jovian planets would be arranged in such a way that a single spacecraft from Earth could visit them all on a single mission relatively easily.

Front 2

About how often do the Jovian planets “line up” so that a mission like Voyager is possible?

Back 2

Once every roughly 175 years.

Front 3

What did the Pioneer probes discover about Jupiter's radiation belts?

Back 3

They are more than 10,000 times as strong as Earth's radiation belts -- too dangerous to send a spacecraft into the strongest parts of.

Front 4

“Three million amps” of electricity flow between Jupiter and what other object?

Back 4

The innermost of the Galilean satellites, Io.

Front 5

What moon is bigger than the planet Mercury?

Back 5

Jupiter's Ganymede, the largest moon in the Solar System.

Front 6

What are the “spokes” in Saturn's rings?

Back 6

They are made of dusty particles, lifted away from the rings by electric and magnetic effects.

Front 7

What is the likely origin of Saturn's rings?

Back 7

They may have been formed by the destruction of small moons close to the planet.

Front 8

Which of the Jovian planets radiate more heat than they receive from the Sun?

Back 8

Jupiter and Saturn.

Front 9

What is a possible explanation for the odd appearance of the moon Miranda?

Back 9

It may have been broken apart by impact, and have settled back together in a jumble.

Front 10

What planet has the fastest winds in the solar system?

Back 10

Neptune

Front 11

What is odd about the orbit of Triton around Neptune? Why might it be that way?

Back 11

Triton's orbit is "retrograde": the opposite direction from the direction that Neptune spins. As seen from the North, Neptune spins and orbits counter-clockwise, but Triton orbits around Neptune clockwise. Triton may have originated as a separate Kuiper Belt Object which was later captured into its odd orbit by Neptune.